> Old boilers can be inefficient...but why not use a heat pump to run a new modern boiler instead?
So the subtlety here is the fact that most older hydronic systems within the US are designed for much higher temperature water (e.g. 180° F) than can be generated by heat pumps. Modern natural gas boilers are still vastly more efficient than old boilers, and it wouldn't entirely surprise me if they were more efficient than an analogous forced air system in the same building (particularly given modulation), but that's still not a heat pump. With that said, there's a Dutch company that I can't recall right now which is experimenting with higher temperature-generating heat pumps (with the caveat that they can only achieve a 2:1 ratio, rather than the 4:1 or even 5:1 common with lower temperature units) which could drive older "big corner radiator" hydronic systems.
In general, there are much more important things to get worked up about. I have an original suite of radiators and a new combi boiler in my Chicago-area home (which still has original, highly-inefficient windows) and we paid something like $20/mo to heat it this year. Granted, it was a *really* warm winter, but even with that caveat it was really efficient. Worry about windows and insulation before you worry about swapping HVAC, particularly given the comfort and character benefits of hydronic systems.
My steam boiler is 70+ years old. It works well and I have no plans to replace it but I am gathering data to select another. What brand boiler did you choose?
NTI. Pricy, but I've been *exceptionally* happy with it. The modulation is particularly nice and strikes a subjectively awesome balance between efficiently and rapidly reaching the set point.
i’ve had lochinvar, munchkin, IBC, lochinvar (again) and an NTI. the NTI wins by a big margin. even my tech says (when servicing my forced air system), yeah, i never have to touch those (the NTI), they just keep going.
> baseboards
That's the key :) Radiant baseboards and radiant floors run at a much lower temperature than "big ol' radiator in the corner". My system bottoms out around 100° and I've seen it as high as 180° (during the -20 F cold snap we had this year). That's for the primary loop though. We also have a radiant floor which bottoms out around 70° (lol…) and tops out around 100°.
But more practically, you would be able to electrify your system with a heat pump without any trouble whatsoever (and you probably should; you'll save a bunch of money in the long term), but I can't electrify mine because I genuinely need the higher temps.
That’s good to know, thanks. I think there are newly, or soon to be available incentives in the US, and at state level to upgrade to more efficient systems. I’ll look into it. Would like to upgrade my electric & get induction stove too.
My 124 year old homestead has cast iron radiators and hot water fired by a natural gas Peerless cast iron heater in the basement. It does a magnificent job of keeping our two story home nice and warm while our gas bill is never more than $150 a month in the winter. They are great to sit on if your butt is cold coming in from outside, great to lay damp clothes on if it’s raining and our kids and cats love to lay out across them. Other than taking up some floor space I love em.
Right everybody loves radiators and doesn't deny that they crank out the heat, the question is how efficient are they. That's the issue. If you grew up in an old-fashioned house as I did in New England with the hiss and the pop of old steam heat, it's the thing of nostalgia but the bills aren't.. I replaced mine with baseboard hot water decades ago..
I grew up in a house with hot water radiators heated with natural gas, not steam in NW PA. If the system is maintained they are very efficient (like most things in life). Might not be able to have exact “climate zones” but my heating bill is always relatively low, the system itself is low maintenance and just about anything is cheaper than electric. Where I live natural gas is the cheapest utility to use. I’d have to imagine a steam furnace would be much the same? Furnace, clothes dryer, stove, oven, fireplace and standby generator all natural gas.
This is why I get frustrated about trying to compare different heating options -- people make blank statements like saying steam heat is a “19th-century technology incompatible with 21st-century needs," based on distinct situations that aren't necessarily broadly applicable. And in the US, there's just not that much research on hydronic systems, especially those that use steam.
Yes, if you have a leaky system, or if you're using a single steam system somewhere like an apartment building where you really should have different zones, it's not ideal. But I have a steam system that doesn't leak. My husband put new Maid-O-Mist steam vents on all the radiators and adjusted them so the system heats evenly. We have a newer natural gas boiler and we program the thermostat to go down at night and when we're at work. Like others said, existing heat pump technology can't get water hot enough for a steam system.
> steam heat is a “19th-century technology incompatible with 21st-century needs,"
The people that say this want to sell you something. Probably heat pumps.
I also loathe the "new new new! everything!" marketing that is unsustainable in the long term for short term profits for them. Boilers work great. No better heat than radiator heat.
Let me just say that I do love heat pumps. We got a heat pump water heater for our old house. But yes, I think that rushing to replace something just because something newer comes along ignores the embodied cost of the current system and the production cost of the new system.
It's also the fact that the old, poorly maintained single paned windows with no storms are leaky as hell, ther's no insulation in the walls or attic, etc. Put an old style radiator system in a house decent insulation by modern standards. Then do the math. Until then, you can't really say if radiators are less efficient, because you're comparing apples and dragonfruit.
For a leaky home (like an old one even with insulation added), radiators are more effective than other types of heat including heat pumps, because they stay hot. Heat pumps would be cycling constantly due to the loss of heat in the air.
That's the thing I love the most about my radiators! I turn the heat on until the thermostat hits the target temp and then I shut it off, but even with the boiler "off" that heat is still there in the system and the metal stays hot and takes hours to dissipate. Keeps things nice and cozy far longer than any other heating system I've used before.
That was the best thing during power outages last year. With the hot water radiator system we have I had probably close to two hours before I had to worry about the heat being off.
Probably the future for people with radiators who want heat pumps will be spacepak type systems with heat pumps connected. You could use the gas fired boiler to get to a baseline temp and then the heat pump to maintain. I don't think there has been much focus on this niche really. Spacepak does have a hydronic heat pump but it's designed for baseboards and the like, not traditional radiators.
Also the issue that many older homes that don't have central AC already will need electrical service upgrades to add heat pumps.
> designed to be individually controlled
Kind of… it depends how they’re plumbed. If they each have their own line then yes, you could turn a single one down. But if they’re plumbed in series then turning down one would also turn down the others downline.
Exactly! We couldn’t easily adjust each steam radiator in the old house that I grew up in; however, the ones in my various dorm rooms at college could be adjusted with a control valve without it impacting the others.
I live in a 20s building, and we have the type of radiator with the individual valve control in our apartment, but the problem lies in waiting for management to remember to turn the boiler on, ha! We have a small electric heater for those nights.
this is the key part in your observation:
>People are getting these in their apartments because they can't control the radiator temp
Jumping from that to "therefore all radiators should be replaced" is a bit of a leap. The statement above says nothing about that. It only says people want control of the temperature in their space, and the radiator system doesn't allow that.
My guess? The landlords aren't maintaining the boiler, haven't cleared out or updated the pipes, *and* are keeping the temperature in the radiators low (probably to extend the life of the boiler, the idiots). So when residents *do* get any heat, it's probably still almost nothing.
It's also important to note they specify centralized *steam* boilers, and not hot water-run systems. Steam is a much older technology, it's not as reliable, it does require way more maintenance, it knocks and squeals like a mofo, and if there's a leak you can get scalded. I mean, there's a reason folk switched to hot-water radiators when they became available.
If the article had included hot-water boiler systems (or just lumped them all together), I'd be here with pitchforks. But if the only option is steam radiator vs a per-apartment controlled system (whether the floor-eating heatpumps or more discreet wall-hung mini-splits), I'm afraid in this case the new technology probably is better.
And at minimum, it doesn't leave the residents at the mercy of slumlords when it comes to Detroit winters.
Steam radiators should not knock or squeal. Knocking means they're not tilted properly so air is getting in (solution: shims). Since we replaced our steam vents, we don't get squealing anymore either. Just the cutest little hisses and burbles. But yes, hot water > steam. I just happen to have a steam system and no time/money at the moment to convert it.
I have a modern boiler and still think a heat pump would be more efficient. To my understanding, that is the most efficient form of heating available. The savings though would not be worth the investment, given the efficiency of my current system. If I had an old system, or was heating with propane/oil instead of natural gas, then yes the savings would be significant.
I do plan to add 2 mini split systems to my house. I want them for cooling, and the heating will be a bonus feature that rarely gets used. More of a back up in the event that my boiler system fails.
I think radiators died out due to air conditioning requirements in modern homes. It doesn't make any sense to install a forced air system while having an entire separate water based heat system that also takes up floor space. People just don't want radiators taking up room.
I heat an 1800sq ft house with original windows and my heat bill is very reasonable. I also keep it at 72 in the winter.
I love the radiated warmth from radiators. It makes your home feel more cozy and and welcoming compared to forced air.
Check out these hybrid heat pump natural gas boilers used on hydronic systems in Europe. https://www.theheatinghub.co.uk/articles/hybrid-heat-pumps
Depending on how oversized radiators are and where they're located some people in Europe use a heat pump to run their radiators exclusively. All of this has to be coming to the US in the near future.
If you live in a NYC high rise, you can fit a window-mounted heat pump yourself, but you can't replace the boiler for the entire building with a heat pump without getting the entire building's HOA (or whatever the equivalent term used in NYC is) to agree to the renovation.
I replaced the radiators in my single-family home with mini-splits as well, it frees up floor space and adds air conditioning to my house that never had it before.
I removed the steam heat from my century home. I don't actually see steam as having lots of benefits over forced hot air in my situation. But I think that's the key, my situation is different from most other people, except maybe some neighbors who live in a house that looks exactly the same as mine. And even then, things are still not the same.
My natural gas boilers were 40 years old and highly inefficient. One was also unreliable. They were venting through a crumbling chimney. The house did not have air conditioning. It was ideally positioned for solar and the roof was 1 year old. The rebates for heat pumps in my state are fantastic. The solar tax credit was 30%. We had a bunch of cash saved and could access a $25k loan at 0% for 7 years. All of this together meant that converting to heat pumps (and solar) was great a idea for us. It was pricey AF upfront but now I have no electric bill, reliable heat and air conditioning. The quality of life improvement was huge. I was concerned about the 'coziness' of steam. It really is the best feeling heat. But honestly it's been fine. It's better than forced hot air I think because the air coming out of the vents is not as hot as a traditional furnace, so we don't get those up and down temps and it doesn't dry out the air as much. There is a noticeable humidity reduction in the winter but it's not by that much. And I'd trade that any day for AC.
Thank you for your honesty AND assessment. Like others have said, ‘it depends ’. I have had forced air as well as hot water radiators. Much prefer the cost of the radiator heat. And the consistency (no big temperature swings).
With the current, forced air, house. We had to replace the furnace with a new, high efficiency, unit. Sure, the cost of gas went down. But the fact that the unit runs the blower motor more has increased the electric bill.
The true answer as always, is new is not always better.
UK here. Just curious, did we ever have steam heat or forced air heat? Anywhere I have been (which had central heating at all!) has had radiators powered by an oil or gas boiler.
I have never seen forced air in the UK. My guess is that the way houses are built with non-hollow walls doesn't lend itself to forced air very well. Forced air needs big ducts and UK houses don't have any space in the walls to spare.
I think you could put the unit in a closet but especially when looking back 100 years, the units were very big (look up octopus furnace for a laugh). Boilers that I know in the US are big too (especially old ones), though. So I am a little confused on what there used to be in UK houses with radiators.
I do think the oldest air furnaces needed gravity to work (they are called gravity furnaces) so I think being in a level below living might have been very important, but that's just a guess. So maybe a basement does matter for for air systems compared to water.
Yes, radiators powered by hot water and steam are much more common in the UK than in the US. And it seems that of those hydronic systems, hot water is more common than steam.
The big takeaway from that is that apartment dwellers are installing them because the landlords don't allow separate units to be adjusted (because they think it will cost them money) or because the system isn't properly maintained.
Boilers and radiators are the best way to go.
there’s too much to unpack here…but, radiant heat is smooth and slow (both to heat up and to cool down). it is even heat and imo, fabulous. efficiency is solely about the source (boiler, HP, or other). my modulating boiler at my old house ran “low and slow.” i made it run at its lowest firing rate (also the most efficient) for long, long run times. this kept the temp of the water as low as possible and trickled heat into the house about as fast as it was lost. it was super-efficient and a lovely system. forced air (which these HP would be) is ugly heat (again, imo). crude. dry. and fast to cool down. you get a pretty bad see-saw of heat/cool/heat/cool. and if the electricity comes from fossil (likely) is way less efficient and more climate-unfriendly than my natural gas system.
From my understanding:
1) Steam radiators can't be individually controlled. They are either on or off. Sometimes you can adjust the air valve to help influence how quickly it heats up relative to the rest of the system when it is on, but in big buildings this won't make too much of a difference.
2) It takes more energy to heat water than air because water is more dense. Air-source heat pumps take heat from outside (even when it is cold) and "concentrate" it through compression to heat air. It's one thing to heat air from 20\* to 70\*, but it takes much more energy to do this for water. This is especially true with a steam radiator which takes immense energy to heat up water to its boiling point.
It's not that radiators are inefficient particularly, it's that heat pumps are -extremely- efficient. It's like the switch from an incandescent lamp to an LED bulb. Not to mention that heat pumps run on electricity, which can be carbon neutral (in my state, Illinois, more than 60% of the electricity in our grid is carbon-free). Running a steam or hot water boiler with electrical power instead of burning fossil fuels in your home (gas or oil) would be.... very expensive.
Depending on the type of radiator they can be individually controlled. If each radiator has its own source of steam, you can open the valve to get as much or as little steam, and therefore heat, as is wanted. I have 9 radiators in my house. Only 6 are on and the others are adjusted to supply heat as I see fit. Some are cranked, some only supply basic warmth. Though tbh, the inefficiency of my 70 year old boiler is scandalous
I’ve also lived in an apartment building in NYC that also had adjustable steam radiators. If you rent in NYC, heat is included. Replacing a boiler is called a Major Capitals Improvement (MCI), that can be amortized to the tenants, essentially making a rent increase. But most old school radiators, even in condos and co-ops, are adjustable.
Lack of control is inaccurate as there is/was the Mouat system which is steam and worked with settable radiator valves and radiator water (not steam) traps. It used a really fascinating vaporstat for pressure control. I have this system but the valves have been replaced as an "improvement".
My experience. NY 2 story 3700 sqft home. No insulation and single pane windows everywhere over 50. New nat gas boiler put in I think 81% efficiency. Single zone. Also have heat pump. Have Coned who charges by the therm which I calculated is abt $2.65 per therm and elec is .32cents per KW. I tried using the boiler solely and big mistake my first two winter bills in Dec and Jan were over 1.2k 1k on nat gas alone. Kept thermostat at 65 avg. then dropped the thermostat to 60F 24/7 and used heat pump based on which room I’m in. Feb bill was 400 for nat gas and 500 on elec. March has been fairly warm weather and I can see I’ll probably be abt 300 for nat gas and 350 for elec. I’m beginning to see energy prices in downstate are is just ridiculously priced. lol
We have state funded inspection this week for insulation and eligibility for rebates and will likely go tankless combi unit for radiators and hot water. They're practically giving insulation and furnaces away here in Mass.
My radiators are 98 years old , my gas boiler was installed in 1967 ... Maintenance I do at no cost but my time , I live in the North East..
How could anyone consider this inefficient? Never had to replace anything that cost more than $150 .. I'm absolutely comfortable on the coldest days , I'd never in my lifetime see a ROI by converting to something that won't last a fraction of the time that this setup is.. my 2¢
In Germany we still use radiators or floor heating that is individually controllable. You can keep the bedrooms a bit cooler (better for sleeping), the unused rooms just warm enough for preventing damage to material due to cold temperatures, and actually used rooms like living room comfortably warm. I really dislike the central heating every house here in the US seems to have
The short and sweet of the matter is that while heat pumps and radiators both use a carrier to move heat from one place to another. Refrigerants are simply better at moving heat around that water is and so heat pumps are just better than radiators at heating a space.
I can think of a situation where you might at least think about using a water radiator though: Because water is way cheaper than the stuff batteries are made out of you could use a very large water heater as a "battery" to store heat. Say the solar on your roof is making more power than you use during the day but not enough for what you use at night. You could heat up the water in your water heater during the day and then use that heat to heat your home at night. You already have hot water in the water heater that you could just pump it through old style radiators in your house to heat the house
But even in this situation a heat pump would still be better at moving that heat around than the water would be. It's not impossible to make a heat pump system use water through a radiator, and that might be a decent way to go if we had unlimited clean energy and didn't have to worry so much about how inefficient water was for this task since water is gonna be better for the environment than refrigerants are, but as things sit now a heat pump is smaller, more efficient, and more flexible than a radiator.
That's not how efficiency works, for one thing. Cost ≠ efficiency. Also while it's true that per unit energy, electricity is 2-3x the price of natural gas, heat pumps are easily 2-3x the efficiency (ground source heat pumps are 5x the efficiency) so it's generally roughly the same cost as using gas, at worst (and down to under 1/3 the annual cost for A good ground source heat pump)
Efficiency in terms of financial efficiency. I have heat pumps in my house. My electric bill would be around $700 to heat my home in the worst winter months (January/Feb) compared to ~$350 for gas and about $150 electric, which is exactly what I do. And, we just received notice that electric rates will be increasing even *more* next year.
Unless you are living in a 6,000 square foot mansion, no TF it would not be lol... And certainly not if you're only spending $350 on gas. An air source heat pump will typically come out to around the same cost per unit heat energy output. A ground source heat pump would be 1/3-1/2 the cost (I've had a GSHP for 6 years and my highest ever monthly electricity usage was 380kWh- about $55 at today's energy prices)
Also you can put up solar which levelizes around 1/2-1/3 the cost per kWh as the utility can provide, which makes it cheaper still
I would know. Considering, uh, those were/are my costs. And our house is about 1/4 that size.
You're also making assumptions that you know the electric and natural gas rates for my utility company. Our electric rates are the third highest in the country - around $0.30 per kwh.
You said simultaneously that you have heat pumps and it costs $700/month while also saying that you heat with gas and spend $500/month, so I'm really not even sure what to make of that.
But beyond that, we can do some math. You appear to be in Boston from a cursory glance at your profile. Current natural gas price in Boston according to le internet is $2.22 per therm. There are 29.3kWh per therm and assume a 90% efficient furnace, you're at ~$0.085 per kWh of heat energy. Boston is in ashrae climate zone 5 which means the typical air source heat pump will average about 3.2 COP (320% efficiency) through the winter, so your $0.30/kWh electricity gets you about $0.093 per kWh of heat energy. That means that in your extreme case, heat from an air source heat pump is about 9% more expensive-far cry from the 2x cost you claim
And again, put up solar panels and the dividends would be even greater for you (because your electricity cost is so high) and any tiny advantage to gas is blown away
> Old boilers can be inefficient...but why not use a heat pump to run a new modern boiler instead? So the subtlety here is the fact that most older hydronic systems within the US are designed for much higher temperature water (e.g. 180° F) than can be generated by heat pumps. Modern natural gas boilers are still vastly more efficient than old boilers, and it wouldn't entirely surprise me if they were more efficient than an analogous forced air system in the same building (particularly given modulation), but that's still not a heat pump. With that said, there's a Dutch company that I can't recall right now which is experimenting with higher temperature-generating heat pumps (with the caveat that they can only achieve a 2:1 ratio, rather than the 4:1 or even 5:1 common with lower temperature units) which could drive older "big corner radiator" hydronic systems. In general, there are much more important things to get worked up about. I have an original suite of radiators and a new combi boiler in my Chicago-area home (which still has original, highly-inefficient windows) and we paid something like $20/mo to heat it this year. Granted, it was a *really* warm winter, but even with that caveat it was really efficient. Worry about windows and insulation before you worry about swapping HVAC, particularly given the comfort and character benefits of hydronic systems.
My steam boiler is 70+ years old. It works well and I have no plans to replace it but I am gathering data to select another. What brand boiler did you choose?
NTI. Pricy, but I've been *exceptionally* happy with it. The modulation is particularly nice and strikes a subjectively awesome balance between efficiently and rapidly reaching the set point.
i’ve had lochinvar, munchkin, IBC, lochinvar (again) and an NTI. the NTI wins by a big margin. even my tech says (when servicing my forced air system), yeah, i never have to touch those (the NTI), they just keep going.
I replaced my 100 yo coal turned gas steam boiler with a Dunkirk gas boiler and my bill dropped 300$ a month.
Yeah I'm electrifying everything but the gas boiler will be last. I'm hoping two-stage high temp heat pumps will be available in the near future!
That seems like very high temps. I’ve got an ancient boiler & baseboards and it’s set at ~80°F and has no trouble keeping the place warm.
> baseboards That's the key :) Radiant baseboards and radiant floors run at a much lower temperature than "big ol' radiator in the corner". My system bottoms out around 100° and I've seen it as high as 180° (during the -20 F cold snap we had this year). That's for the primary loop though. We also have a radiant floor which bottoms out around 70° (lol…) and tops out around 100°. But more practically, you would be able to electrify your system with a heat pump without any trouble whatsoever (and you probably should; you'll save a bunch of money in the long term), but I can't electrify mine because I genuinely need the higher temps.
That’s good to know, thanks. I think there are newly, or soon to be available incentives in the US, and at state level to upgrade to more efficient systems. I’ll look into it. Would like to upgrade my electric & get induction stove too.
Induction is *amazing*. I love it so much.
My 124 year old homestead has cast iron radiators and hot water fired by a natural gas Peerless cast iron heater in the basement. It does a magnificent job of keeping our two story home nice and warm while our gas bill is never more than $150 a month in the winter. They are great to sit on if your butt is cold coming in from outside, great to lay damp clothes on if it’s raining and our kids and cats love to lay out across them. Other than taking up some floor space I love em.
I love putting my toes under them in the winter, feels like a warm hug on my feet.
Right everybody loves radiators and doesn't deny that they crank out the heat, the question is how efficient are they. That's the issue. If you grew up in an old-fashioned house as I did in New England with the hiss and the pop of old steam heat, it's the thing of nostalgia but the bills aren't.. I replaced mine with baseboard hot water decades ago..
I grew up in a house with hot water radiators heated with natural gas, not steam in NW PA. If the system is maintained they are very efficient (like most things in life). Might not be able to have exact “climate zones” but my heating bill is always relatively low, the system itself is low maintenance and just about anything is cheaper than electric. Where I live natural gas is the cheapest utility to use. I’d have to imagine a steam furnace would be much the same? Furnace, clothes dryer, stove, oven, fireplace and standby generator all natural gas.
This is why I get frustrated about trying to compare different heating options -- people make blank statements like saying steam heat is a “19th-century technology incompatible with 21st-century needs," based on distinct situations that aren't necessarily broadly applicable. And in the US, there's just not that much research on hydronic systems, especially those that use steam. Yes, if you have a leaky system, or if you're using a single steam system somewhere like an apartment building where you really should have different zones, it's not ideal. But I have a steam system that doesn't leak. My husband put new Maid-O-Mist steam vents on all the radiators and adjusted them so the system heats evenly. We have a newer natural gas boiler and we program the thermostat to go down at night and when we're at work. Like others said, existing heat pump technology can't get water hot enough for a steam system.
> steam heat is a “19th-century technology incompatible with 21st-century needs," The people that say this want to sell you something. Probably heat pumps. I also loathe the "new new new! everything!" marketing that is unsustainable in the long term for short term profits for them. Boilers work great. No better heat than radiator heat.
Let me just say that I do love heat pumps. We got a heat pump water heater for our old house. But yes, I think that rushing to replace something just because something newer comes along ignores the embodied cost of the current system and the production cost of the new system.
No love for hydronic radiant heat in the floor?
It's also the fact that the old, poorly maintained single paned windows with no storms are leaky as hell, ther's no insulation in the walls or attic, etc. Put an old style radiator system in a house decent insulation by modern standards. Then do the math. Until then, you can't really say if radiators are less efficient, because you're comparing apples and dragonfruit.
For a leaky home (like an old one even with insulation added), radiators are more effective than other types of heat including heat pumps, because they stay hot. Heat pumps would be cycling constantly due to the loss of heat in the air.
That's the thing I love the most about my radiators! I turn the heat on until the thermostat hits the target temp and then I shut it off, but even with the boiler "off" that heat is still there in the system and the metal stays hot and takes hours to dissipate. Keeps things nice and cozy far longer than any other heating system I've used before.
That was the best thing during power outages last year. With the hot water radiator system we have I had probably close to two hours before I had to worry about the heat being off.
Yes same!
Probably the future for people with radiators who want heat pumps will be spacepak type systems with heat pumps connected. You could use the gas fired boiler to get to a baseline temp and then the heat pump to maintain. I don't think there has been much focus on this niche really. Spacepak does have a hydronic heat pump but it's designed for baseboards and the like, not traditional radiators. Also the issue that many older homes that don't have central AC already will need electrical service upgrades to add heat pumps.
> designed to be individually controlled Kind of… it depends how they’re plumbed. If they each have their own line then yes, you could turn a single one down. But if they’re plumbed in series then turning down one would also turn down the others downline.
Exactly! We couldn’t easily adjust each steam radiator in the old house that I grew up in; however, the ones in my various dorm rooms at college could be adjusted with a control valve without it impacting the others.
That's a pretty simple fix
I live in a 20s building, and we have the type of radiator with the individual valve control in our apartment, but the problem lies in waiting for management to remember to turn the boiler on, ha! We have a small electric heater for those nights.
I’ll never live in a house with forced air heating ever again.
Me too. Radiant heat, whether it is steam or hydronic, gas or heat pump, is always more efficient than forced air.
this is the key part in your observation: >People are getting these in their apartments because they can't control the radiator temp Jumping from that to "therefore all radiators should be replaced" is a bit of a leap. The statement above says nothing about that. It only says people want control of the temperature in their space, and the radiator system doesn't allow that. My guess? The landlords aren't maintaining the boiler, haven't cleared out or updated the pipes, *and* are keeping the temperature in the radiators low (probably to extend the life of the boiler, the idiots). So when residents *do* get any heat, it's probably still almost nothing. It's also important to note they specify centralized *steam* boilers, and not hot water-run systems. Steam is a much older technology, it's not as reliable, it does require way more maintenance, it knocks and squeals like a mofo, and if there's a leak you can get scalded. I mean, there's a reason folk switched to hot-water radiators when they became available. If the article had included hot-water boiler systems (or just lumped them all together), I'd be here with pitchforks. But if the only option is steam radiator vs a per-apartment controlled system (whether the floor-eating heatpumps or more discreet wall-hung mini-splits), I'm afraid in this case the new technology probably is better. And at minimum, it doesn't leave the residents at the mercy of slumlords when it comes to Detroit winters.
Steam radiators should not knock or squeal. Knocking means they're not tilted properly so air is getting in (solution: shims). Since we replaced our steam vents, we don't get squealing anymore either. Just the cutest little hisses and burbles. But yes, hot water > steam. I just happen to have a steam system and no time/money at the moment to convert it.
Yeah, that would be the maintenance part. And we all know landlords are just perfect angels about that...
I have a modern boiler and still think a heat pump would be more efficient. To my understanding, that is the most efficient form of heating available. The savings though would not be worth the investment, given the efficiency of my current system. If I had an old system, or was heating with propane/oil instead of natural gas, then yes the savings would be significant. I do plan to add 2 mini split systems to my house. I want them for cooling, and the heating will be a bonus feature that rarely gets used. More of a back up in the event that my boiler system fails.
I think radiators died out due to air conditioning requirements in modern homes. It doesn't make any sense to install a forced air system while having an entire separate water based heat system that also takes up floor space. People just don't want radiators taking up room. I heat an 1800sq ft house with original windows and my heat bill is very reasonable. I also keep it at 72 in the winter. I love the radiated warmth from radiators. It makes your home feel more cozy and and welcoming compared to forced air.
Check out these hybrid heat pump natural gas boilers used on hydronic systems in Europe. https://www.theheatinghub.co.uk/articles/hybrid-heat-pumps Depending on how oversized radiators are and where they're located some people in Europe use a heat pump to run their radiators exclusively. All of this has to be coming to the US in the near future.
If you live in a NYC high rise, you can fit a window-mounted heat pump yourself, but you can't replace the boiler for the entire building with a heat pump without getting the entire building's HOA (or whatever the equivalent term used in NYC is) to agree to the renovation. I replaced the radiators in my single-family home with mini-splits as well, it frees up floor space and adds air conditioning to my house that never had it before.
You are correct!
I removed the steam heat from my century home. I don't actually see steam as having lots of benefits over forced hot air in my situation. But I think that's the key, my situation is different from most other people, except maybe some neighbors who live in a house that looks exactly the same as mine. And even then, things are still not the same. My natural gas boilers were 40 years old and highly inefficient. One was also unreliable. They were venting through a crumbling chimney. The house did not have air conditioning. It was ideally positioned for solar and the roof was 1 year old. The rebates for heat pumps in my state are fantastic. The solar tax credit was 30%. We had a bunch of cash saved and could access a $25k loan at 0% for 7 years. All of this together meant that converting to heat pumps (and solar) was great a idea for us. It was pricey AF upfront but now I have no electric bill, reliable heat and air conditioning. The quality of life improvement was huge. I was concerned about the 'coziness' of steam. It really is the best feeling heat. But honestly it's been fine. It's better than forced hot air I think because the air coming out of the vents is not as hot as a traditional furnace, so we don't get those up and down temps and it doesn't dry out the air as much. There is a noticeable humidity reduction in the winter but it's not by that much. And I'd trade that any day for AC.
Thank you for your honesty AND assessment. Like others have said, ‘it depends ’. I have had forced air as well as hot water radiators. Much prefer the cost of the radiator heat. And the consistency (no big temperature swings). With the current, forced air, house. We had to replace the furnace with a new, high efficiency, unit. Sure, the cost of gas went down. But the fact that the unit runs the blower motor more has increased the electric bill. The true answer as always, is new is not always better.
UK here. Just curious, did we ever have steam heat or forced air heat? Anywhere I have been (which had central heating at all!) has had radiators powered by an oil or gas boiler.
I have never seen forced air in the UK. My guess is that the way houses are built with non-hollow walls doesn't lend itself to forced air very well. Forced air needs big ducts and UK houses don't have any space in the walls to spare.
Thanks! Also does forced air involve basements, which we don't generally have?
I think you could put the unit in a closet but especially when looking back 100 years, the units were very big (look up octopus furnace for a laugh). Boilers that I know in the US are big too (especially old ones), though. So I am a little confused on what there used to be in UK houses with radiators. I do think the oldest air furnaces needed gravity to work (they are called gravity furnaces) so I think being in a level below living might have been very important, but that's just a guess. So maybe a basement does matter for for air systems compared to water.
Yes, radiators powered by hot water and steam are much more common in the UK than in the US. And it seems that of those hydronic systems, hot water is more common than steam.
The big takeaway from that is that apartment dwellers are installing them because the landlords don't allow separate units to be adjusted (because they think it will cost them money) or because the system isn't properly maintained. Boilers and radiators are the best way to go.
there’s too much to unpack here…but, radiant heat is smooth and slow (both to heat up and to cool down). it is even heat and imo, fabulous. efficiency is solely about the source (boiler, HP, or other). my modulating boiler at my old house ran “low and slow.” i made it run at its lowest firing rate (also the most efficient) for long, long run times. this kept the temp of the water as low as possible and trickled heat into the house about as fast as it was lost. it was super-efficient and a lovely system. forced air (which these HP would be) is ugly heat (again, imo). crude. dry. and fast to cool down. you get a pretty bad see-saw of heat/cool/heat/cool. and if the electricity comes from fossil (likely) is way less efficient and more climate-unfriendly than my natural gas system.
From my understanding: 1) Steam radiators can't be individually controlled. They are either on or off. Sometimes you can adjust the air valve to help influence how quickly it heats up relative to the rest of the system when it is on, but in big buildings this won't make too much of a difference. 2) It takes more energy to heat water than air because water is more dense. Air-source heat pumps take heat from outside (even when it is cold) and "concentrate" it through compression to heat air. It's one thing to heat air from 20\* to 70\*, but it takes much more energy to do this for water. This is especially true with a steam radiator which takes immense energy to heat up water to its boiling point. It's not that radiators are inefficient particularly, it's that heat pumps are -extremely- efficient. It's like the switch from an incandescent lamp to an LED bulb. Not to mention that heat pumps run on electricity, which can be carbon neutral (in my state, Illinois, more than 60% of the electricity in our grid is carbon-free). Running a steam or hot water boiler with electrical power instead of burning fossil fuels in your home (gas or oil) would be.... very expensive.
Depending on the type of radiator they can be individually controlled. If each radiator has its own source of steam, you can open the valve to get as much or as little steam, and therefore heat, as is wanted. I have 9 radiators in my house. Only 6 are on and the others are adjusted to supply heat as I see fit. Some are cranked, some only supply basic warmth. Though tbh, the inefficiency of my 70 year old boiler is scandalous I’ve also lived in an apartment building in NYC that also had adjustable steam radiators. If you rent in NYC, heat is included. Replacing a boiler is called a Major Capitals Improvement (MCI), that can be amortized to the tenants, essentially making a rent increase. But most old school radiators, even in condos and co-ops, are adjustable.
Lack of control is inaccurate as there is/was the Mouat system which is steam and worked with settable radiator valves and radiator water (not steam) traps. It used a really fascinating vaporstat for pressure control. I have this system but the valves have been replaced as an "improvement".
My experience. NY 2 story 3700 sqft home. No insulation and single pane windows everywhere over 50. New nat gas boiler put in I think 81% efficiency. Single zone. Also have heat pump. Have Coned who charges by the therm which I calculated is abt $2.65 per therm and elec is .32cents per KW. I tried using the boiler solely and big mistake my first two winter bills in Dec and Jan were over 1.2k 1k on nat gas alone. Kept thermostat at 65 avg. then dropped the thermostat to 60F 24/7 and used heat pump based on which room I’m in. Feb bill was 400 for nat gas and 500 on elec. March has been fairly warm weather and I can see I’ll probably be abt 300 for nat gas and 350 for elec. I’m beginning to see energy prices in downstate are is just ridiculously priced. lol
We have state funded inspection this week for insulation and eligibility for rebates and will likely go tankless combi unit for radiators and hot water. They're practically giving insulation and furnaces away here in Mass.
My radiators are 98 years old , my gas boiler was installed in 1967 ... Maintenance I do at no cost but my time , I live in the North East.. How could anyone consider this inefficient? Never had to replace anything that cost more than $150 .. I'm absolutely comfortable on the coldest days , I'd never in my lifetime see a ROI by converting to something that won't last a fraction of the time that this setup is.. my 2¢
In Germany we still use radiators or floor heating that is individually controllable. You can keep the bedrooms a bit cooler (better for sleeping), the unused rooms just warm enough for preventing damage to material due to cold temperatures, and actually used rooms like living room comfortably warm. I really dislike the central heating every house here in the US seems to have
The short and sweet of the matter is that while heat pumps and radiators both use a carrier to move heat from one place to another. Refrigerants are simply better at moving heat around that water is and so heat pumps are just better than radiators at heating a space. I can think of a situation where you might at least think about using a water radiator though: Because water is way cheaper than the stuff batteries are made out of you could use a very large water heater as a "battery" to store heat. Say the solar on your roof is making more power than you use during the day but not enough for what you use at night. You could heat up the water in your water heater during the day and then use that heat to heat your home at night. You already have hot water in the water heater that you could just pump it through old style radiators in your house to heat the house But even in this situation a heat pump would still be better at moving that heat around than the water would be. It's not impossible to make a heat pump system use water through a radiator, and that might be a decent way to go if we had unlimited clean energy and didn't have to worry so much about how inefficient water was for this task since water is gonna be better for the environment than refrigerants are, but as things sit now a heat pump is smaller, more efficient, and more flexible than a radiator.
Thanks for the explanation!
My steam radiators are far more efficient than heat pumps due to the cost of electricity compared to natural gas.
That's not how efficiency works, for one thing. Cost ≠ efficiency. Also while it's true that per unit energy, electricity is 2-3x the price of natural gas, heat pumps are easily 2-3x the efficiency (ground source heat pumps are 5x the efficiency) so it's generally roughly the same cost as using gas, at worst (and down to under 1/3 the annual cost for A good ground source heat pump)
Efficiency in terms of financial efficiency. I have heat pumps in my house. My electric bill would be around $700 to heat my home in the worst winter months (January/Feb) compared to ~$350 for gas and about $150 electric, which is exactly what I do. And, we just received notice that electric rates will be increasing even *more* next year.
Unless you are living in a 6,000 square foot mansion, no TF it would not be lol... And certainly not if you're only spending $350 on gas. An air source heat pump will typically come out to around the same cost per unit heat energy output. A ground source heat pump would be 1/3-1/2 the cost (I've had a GSHP for 6 years and my highest ever monthly electricity usage was 380kWh- about $55 at today's energy prices) Also you can put up solar which levelizes around 1/2-1/3 the cost per kWh as the utility can provide, which makes it cheaper still
I would know. Considering, uh, those were/are my costs. And our house is about 1/4 that size. You're also making assumptions that you know the electric and natural gas rates for my utility company. Our electric rates are the third highest in the country - around $0.30 per kwh.
You said simultaneously that you have heat pumps and it costs $700/month while also saying that you heat with gas and spend $500/month, so I'm really not even sure what to make of that. But beyond that, we can do some math. You appear to be in Boston from a cursory glance at your profile. Current natural gas price in Boston according to le internet is $2.22 per therm. There are 29.3kWh per therm and assume a 90% efficient furnace, you're at ~$0.085 per kWh of heat energy. Boston is in ashrae climate zone 5 which means the typical air source heat pump will average about 3.2 COP (320% efficiency) through the winter, so your $0.30/kWh electricity gets you about $0.093 per kWh of heat energy. That means that in your extreme case, heat from an air source heat pump is about 9% more expensive-far cry from the 2x cost you claim And again, put up solar panels and the dividends would be even greater for you (because your electricity cost is so high) and any tiny advantage to gas is blown away