Looking for manufacturers of air-water heatpumps for hot water + hydronic heat

bvz2000

I live in the U.S. (Northern California specifically)

I am in the early stages of planning a new heating system for my house. I intend to install under-floor hydronic heating (or, less likely but still possibly: radiators).

I am looking for the names of manufacturers that sell air-water heat pumps that can supply both hot water for heating as well as for consumption. Most companies that I find via google either don't sell anything in the U.S. at all, or only sell a subset of their products here - and do not include air-water heat pumps.

I can find Air-air, and I can find air-water hot water only systems. But not air-water systems that do both heating and hot water.

Can anyone name a few companies that might sell this kind of equipment? I am just trying to do my research and understand my options (and pros and cons) before I talk to a contractor.

Thanks!

Hot_water_fan

Spacepak, Nordic to a name a few. They’re niche right now in the US. If you’re building a higher performance house, the heat loss will be low in that climate. That means the floors will not be particularly warm. You’ll get some of the benefits of in-floor radiant, but not the warm toes part. 

bvz2000

Thanks for the names. I will take a look at them.

I am just a homeowner and not an expert (or even knowledgeable) about HVAC stuff. What I think you are saying is that if my house is very well insulated that the amount of heat I would be using in the floor would be too low to really feel against my feet?

That would be fine by me, unless there is some other reason not to do under floor heat vs. radiators.

This is a retrofit on top of a very cheaply built house though. Most likely it would not be considered a higher performance house. I have added as much insulation to the walls as they will take (and am considering adding additional insulation on the outside at some point), but I am guessing the heat loss is still going to be fairly significant.

I am designing a remodel right now and need to figure out whether I am going to use radiators or under floor heat. I also need to figure out how much space to carve out for the heating/water heating. At the moment I have a tankless on the outside wall as well as an old, 1970's gas wall heater that pretty much does nothing but consume my energy $ without properly heating the house well. I will need to design a space where the heat pump, tanks, and any manifolds would live (and use as little space as possible as my house is only 1100 square feet with no garage).

Thanks again.

Hot_water_fan

What I think you are saying is that if my house is very well insulated that the amount of heat I would be using in the floor would be too low to really feel against my feet?

Exactly - the better you insulate, the lower the temperature will be. How much gas do you use per year? I think you’ll find that your heat loss will be rather low no matter what. You’re probably talking max floor temps of 75-80 on the coldest day of the year. 

The other reason would be that in-floor radiant is extremely expensive when compared to alternatives, especially for a house that size. 

Larry Weingarten

Hi, Here's some info to have a look at: https://redwoodenergy.net/research/

Yours, Larry

bvz2000

Hot_water_fan said:

What I think you are saying is that if my house is very well insulated that the amount of heat I would be using in the floor would be too low to really feel against my feet?

Exactly - the better you insulate, the lower the temperature will be. How much gas do you use per year? I think you’ll find that your heat loss will be rather low no matter what. You’re probably talking max floor temps of 75-80 on the coldest day of the year. 

The other reason would be that in-floor radiant is extremely expensive when compared to alternatives, especially for a house that size. 

Thanks for the explanation. I would have to take a look at our gas usage... I don't have the actual numbers in front of me. But I do know that we generally are cold all winter long. The wall heater just throws heat up into the skylight (where I have a fan hanging from ropes to blow the heat around - but it does not get into the various rooms very well and I hate to leave it on for endless stretches at a time). The other uses for gas in the house are a fireplace (that does a decent job of heating the living room if we leave it on long enough) and our stove/oven and, finally, the tankless hot water heater. So the new heating system would generally replace the hot water heater and the heating system.

I considered forced air heat (and would use an air-air heat pump for that I guess?) but my wife has some pretty significant allergies and I figured that radiant heat would be much better in that regard.

I am pretty handy (I have rewired large parts of the house, done basic plumbing, framing, drywalling, etc.) so I am considering installing the under-floor pex tubing myself. The big impediment there is that I am no longer a spring chicken and my dirt crawlspace is about 20" high at its highest. Not fun under the best of circumstances. And I would have to cut off a TON of nails that are sticking through the floor (with all of the steps needed to prevent a spark-initiated fire). It is part of the reason I am considering radiators as well. That would be a lot less time and work under the house for me to do a DIY install (at least to my untrained eye). None of this is happening in the next year anyway.

For the moment I am mostly interested in researching air-water heat pumps to figure out their pros and cons, costs, and (since I am planning the first stages of the remodel right now) space requirements. Once I have a little bit of knowledge then I hope to start talking to local experts and see what they have to offer.

Thanks again!

bvz2000

Larry Weingarten said:

Hi, Here's some info to have a look at: https://redwoodenergy.net/research/

Yours, Larry

Thanks for the link. I will dig through it over the next few days.

psb75

There is another Canadian company called Arctic in Manitoba. Nordic is in NB. Spacepak is in MA. There is the option of using a product like Warmboard or Sunboard on top of your existing floors for tubing.

Dave H_2

Excellent timing as this will be available later this year. As others have said, it is all about the envelop of the house, tighten up as much as you can, insulate, insulate, insulate...

https://tacocomfort.com/system-m/

Dave H.

bvz2000

Dave H_2 said:

Excellent timing as this will be available later this year. As others have said, it is all about the envelop of the house, tighten up as much as you can, insulate, insulate, insulate...

https://tacocomfort.com/system-m/

Dave H.

Dave,

Thanks! That looks very interesting as well.

I am considering putting a layer of external insulation on the house since I have already filled the walls (with varying degrees of efficacy - I had to pull the drywall in the bedroom a few years ago and found that the blown in insulation had settled and was only filling about 75-80% of the cavity.) I'll insulate under the floor once I figure out which way I go with the heat distribution system.

Thanks again!

bvz2000

psb75 said:

There is another Canadian company called Arctic in Manitoba. Nordic is in NB. Spacepak is in MA. There is the option of using a product like Warmboard or Sunboard on top of your existing floors for tubing.

Thanks. I will check Arctic out as well.

I have thought about Warmboard but as far as I can tell I would have to remove my existing hardwood flooring to install it, so it may not work for me. But I will investigate a bit more.

I have also considered putting the water loop into the walls instead. I can easily tear out and re-install the drywall myself... might be an option.

hot_rod

A heat load calc with all the improvements or intended improvements would answer some questions about radiant compatibility

The SpacPak brand is commonly installed in your area, according to wholesalers I visit in No. Cal

Sol_Brother

I have had good success with Chiltrix CX-34 heat pumps for a variety of combinations of radiant, air handler, fan coil heating/cooling and domestic water heating. Rep is Hot Spot Energy in Virginia. They now have a larger model as well that I have not installed. I particularly like their control/display which gives you extremely fine-grained information about the system components and status and ability to adjust parameters.

Derheatmeister

Stiebel Eltron,Viessmann,Artic,Bosch...

DCContrarian

The Chiltrix has the option of also providing domestic hot water, but it's kind of a hack -- the heat pump turns off and switches over to heating water. There's really no advantage over just having a regular water heater in the house. And if you look at the cost you'll see you could buy several water heaters for the price.