Which heat pump? Model #?

What zone panel? Model #?

How did they arrive at sizing? Do they know how to size for an extremely tight house like foam insulation? Seems like a lot of capacity for the size of house in upstate NY. If they oversize the cooling, could be humidity issues as the unit may not run enough to dry the house. Tight houses have a higher humidity load. May need a whole house ventilating dehumidifier.

Also, round diffusers in the ceiling are lousy for heating if that's what is planned upstairs.

a foam insulated icf house and geothermal is overkill. that combination puts roi far into the future.another problem is open loop systems are problimatic. pumping costs can eat up your geothermal savings.

We're actually trying to budget everything and then pick where we want to save (ie do only 2 of the 3 icf, sprayfoam, geothermal). Right now, I think geothermal is going to be the place we decide to save. It's the most costly, we have the option of doing wood which is nearly as cheap to operate (just a little more time and maintenance work).

The geothermal guy had all of the specs (including orientation, window grade, expected insulation etc.) and floor plans for the quote. I was not going to use the bullseye vents, I agree they are useless.

We've had open loop systems before and the pump cost is not bad (for smaller houses at least), particularly if we spring for a variable speed well pump with manager (which is what our geothermal guy recommended). We won't do a closed loop system due to the possibility of negative environmental impact if a pipe ever were to leak or break. The water table contamination risk is not worth it for us.

So does plan B sound like an option? Is it too gimicky? Should I just do an oil furnace and wood furnace and try and make room for another flue? I like the idea of using propane because we intend to do propane hot water and propane backup generator, so I would rather not have an oil tank AND a propane tank too.

Thanks for the help so far, I appreciate it.

Why all (any) the zoning for a 2-level house thats only 2000sq ft? Why would you go out of your way to design ducts to run through an attic?

SR

Here is an interesting alternative to geo. http://www.daikinaltherma.eu/

It has just arrived in the USA from the UK. I'm very impressed!

Are zones overkill in that size house? I've never had the opportunity to have them and I assumed they would be nice to have. I asked about nixing them from the system but was told they would help increase efficiency.

The whole attic run is confusing to me as well. I have a very open first floor so it's possible he was trying to avoid any duct work runs but my architect planned for them, so I would change all the second floor runs to be floor registers.

I guess when I read the bullseye registers on upper walls, I assumed these were returns? But it does call them supplies in the quote...

Does anyone have an opinion on my option B? Has anyone ever done this or heard of it? Again I assume if it's an option for backup for geothermal systems that someone else must have done this. Is it worth exploring it?

greenheat - Why would I be interested in your spam? Air source heat pumps are not an option in the Adirondacks. You just registered today so I'm guessing you haven't had your hand slapped for this type of thing yet, but it's not acceptable.

Why would you think that air-source heat pumps are not an option in the Adirondacks?

SR

Because on average we have 30-45 days per year that are below zero (as per Cornell's data here) and because as far as I know air source heat pumps use the ambient temperature of the air. The majority of them will not work below freezing and those that will, will not work below 0. I don't want a system that is not going to function on the coldest days of the year. I'm willing to take a geothermal system that will get me 'most of the way' on the coldest days, because it uses the near constant temperature of ground water. As far as I know an air source heat pump will get me nothing on these days. And I've never heard of anyone recommending ASHP in my area.

If you are a HVAC professional who has experience with ASHP in cold climates, by all means educate me, but I've never heard anyone say they are a good idea up here.

Air-source HP may be useful where you live depending on your electrical rate. I live in Montreal, we use them down to -10°F.

If you were to do an open loop GSHP the 2-choices I would consider are either geo with active heating/passive cooling with electric plenum resistance heating as backup. The advantage is an all-electric system with very inexpensive cooling as the compressor is not required for A/C.

The 2nd open loop geo option would be a hybrid system using a high efficiency gas forced air furnace such as a Carrier Infinity with a split geothermal HP. The advantage of this system would be gas as the backup and the possibility of using a generator to run the furnace during a blackout. A desuperheater with a buffer tank could supply DHW either to an active tank or an instantaneous gas DHW heater.

Your concerns regarding ground water contamination with closed loop systems, when properly installed, are (largely) unfounded.

SR

The above post should be corrected. Should read:

Air-source HP may be useful where you live depending on your electrical rate. I live in Montreal, we use them down to ~+10°F.

SR

SR- Thanks so much for writing back. I'm really surprised to hear that someone up North uses an Air Source Heat Pump, literally not a single person I know around here has one, nor have any HVAC people I've talked to installed one.

Our old system was an open loop with active heating / passive cooling with electric resistor backup like you described. It worked fine, but I can't find anyone who installs this type of system. I feel like there aren't enough geothermal contractors around for me to get good options.

I am thinking I am going to go with something more along the lines of my plan B. Of course this means I need to start researching oil vs propane furnaces vs my crazy propane water heater with convertor as well as wood furnaces versus add on furnaces.

Thanks for your help though.

If air-source HPs didnt work, the Canadian Federal government would not be offering $500 rebates for Energy Star 14.5 SEER or higher HPs with no restrictions on how far north you live!

Are you aware of the Mitsubishi Zuba air-source HP that can heat down to -22°F
(-30°C) and beyond?

http://www.mitsubishielectric.ca/en/hvac/zuba-central/index.html

Anyone that can install a conventional open loop GSHP should be able to hook-up a unit with passive cooling; its just plumbing. Theres no mystery, its not rocket science!

SR