New Construction HVAC decisions. Geothermal vs. alternatives with upgraded envelope.

[Sigarms]

And this is much easier to control with a tight home and proper humidity controls.

The question is how are you controlling the indoor indoor humidity and how much power are you using? You can only do so much with a variable speed compressor and variable speed blower motor no matter how much you cut it using it off the primary HVAC system.

There is no one perfect solution, and it almost becomes a teeter totter effect when you try multiple soultions within one complete system to achieve one goal which is almost impossible to obtain IMO.

 

[deezler]

All I know is, I definitely prefer a tight house that you control air quality using a very low wattage ERV. A leaky house means it can leak both ways..., and then you can have condensation in all sorts of undesirable places in your wall assemblies. Just because you got lucky with the right amount of leakiness does not make it a good building strategy. Let me guess though, you don't actively monitor you actual indoor air quality, right? Glad it feels comfy but you could still be breathing fairly dirty air in there. A very high % of americans have worse indoor air quality than we do outdoors. People with high VOC paints, formaldehyde flooring, attached garages, cheap carpets, particle board cabinets, air fresheners... all just poisoning ourselves indoors.

Humidity control in a tight house is easy to achieve with a pot of water on the woodstove in the winter, and air-con and a dehumidifier when really needed (rarely) in the summer.

 

[Sigarms]

All I know is, I definitely prefer a tight house that you control air quality using a very low wattage ERV.

May be hard to believe, but if you live in the "country", the air isn't bad to breath to being with. I think we tend to forget this. Now, if you live next to a hog farm, I guess I can understand why you wouldn't want to breath "natural" air LOL

 

[jk96]

May be hard to believe, but if you live in the "country", the air isn't bad to breath to being with. I think we tend to forget this. Now, if you live next to a hog farm, I guess I can understand why you wouldn't want to breath "natural" air LOL

I'm curious what type of air you think an ERV is providing? It's pulling the same natural air into the house from outside that you're fond of, only it's sending it direct to every room and exchanging all of the air in the home a certain amount of times per day.

 

[Sigarms]

I'm curious what type of air you think an ERV is providing? It's pulling the same natural air into the house from outside that you're fond of, only it's sending it direct to every room and exchanging all of the air in the home a certain amount of times per day.

I understand.

It's not that I believe an ERV isn't bad and one shouldn't be used, I just think a house shouldn't be so air tight where one is required. Not the case with a Co2 detector is a gas appliance is being used.

I had actually thought a about one (ERV) at the beginning of the thread on how the house was being built built, but given that for this kind of job that every contractor who quoted it didn't provide a load calculation or at least ensure one was provided if they got the job, kind of knew it was a moot point.

 

[MGH PA]

Had another HVAC contractor bid out a variable speed ASHP. Quoted $28k for a Bryant Evolution Extreme 280A with 3 zones and humidifier. Forgot to specify what type of duct work but thought that was high, too.