Heating and cooling and ventilation advice
Hello. I currently live in a 1920 home in zone 5a (Westchester county, NY). The home from what I can tell is pretty tight but I haven’t done any actually testing. Attic is spray foamed closed cell and I believe some type of foam insulation was added to the exterior walls at some point. Double pane windows, etc. In terms of heating the home is single pipe steam system oil fed with old cast radiators. The home had an addition at one point and they branched off one of the main steam lines and now the entire system is messed up and is just awful in quality. Brought in one of the top steam guys in the area and it can be fixed but really I don’t like steam. More on that in a bit.
The cooling is a 16 year old spacepak and lennox condenser. Unit is in attic and ductwork reaches second and first floor. However lately the unit has been having trouble and may need completely replacement soon. Spacepak is loud but im ok with it. Currently have no erv/dehumidifier/humidifier or any other hvac stuff other than a mini split in an above the garage room that didn’t have access to the radiators or ductwork. I also have gas in the house that feeds my range, DHW, laundry, grill. I have a large 425 btu meter but due to the moratorium on gas appliances where I live I can’t switch to gas boiler.
I plan to live in the house for a long time and want to improve everything. Here is what I think I would like to do. Completely abandon steam system and switch to hot water. New oil boiler, zoned system and run pex to all new more modern panel radiators like runtal, boderus, etc. I would use the oil and hot water radiators during the coldest months.
I would get a new spacepak or unico system and pair with an air to air heat pump and use that to heat home in shoulder seasons and as the cooling system in the summer.
The other option is looking into spacepak Soltice air to water and using that to heat the radiators and keep the oil boiler as a backup? Does air to water heat pump really work for those flat panel radiators? If they can only do 130 max temperature is that enough to comfortably heat a home or would I need to have a lot more radiators than I do with steam or even high temperature water?
And finally because the he feels a bit tight, I want to add an erv but i don’t want to run it through thr spacepak since it’s too loud. I’m thinking putting one in the attic and just using it on the second floor to bring fresh air in to the bedrooms. Bringing to first floor not possible unless you are using spacepak sized ducts or building bulkheads, etc.
does my overall plan make sense? Any advice? I’m having a hard time finding any local hvac companies who have any idea what I am talking about. They only know what they know. They stare blankly at you when you mention air to water/radiant/ erv, etc
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Replies
"The other option is looking into spacepak Soltice air to water and using that to heat the radiators and keep the oil boiler as a backup?"
This will be expensive but works. It will likely be challenging to find a competent and willing installer - air-to-water is extremely rare and this is a complex application.
"Does air to water heat pump really work for those flat panel radiators? If they can only do 130 max temperature is that enough to comfortably heat a home or would I need to have a lot more radiators than I do with steam or even high temperature water?"
They work with panel radiators. If you have a backup boiler, you don't need to size for 130 water anyway but see how much radiation you can fit. Panel radiations are pretty space efficient.
I'd definitely look at Caleffi's Idronics journals if you go the hydronic route!
https://idronics.caleffi.com/magazine/27-air-water-heat-pump-systems
Is air to water going to be mainstream in a decade from now? Anyone know of installers in the NY area?
That's hard to answer, but I would suspect it'll never be mainstream. It will likely be more common since it's hard to be any less common. Hydronics are not popular in the US after like 100 years of their existence because Americans value AC, and will likely value it more in the coming years. Ductwork is the best way to deliver AC and this makes the hydronic system redundant. That's not to say you can't do it, it's just a solution that 99% of Americans probably won't choose.
You sound like you'd be a perfect candidate for Dandelion.
I don't have any direct knowledge of them, just what I've read in their marketing materials. But you should talk with them. They have a limited geographic area but it sounds like you're in it.
Everything I’ve researched about dandelion is that they encourage central forced air or some type of mini split wall radiator that’s blowing hot or cold air. They do not do radiant heat. Someone correct me if I’m wrong.