This is very helpful, thank you. That makes sense about the single stage vs two stage and the zoning.

I have the model numbers for the heat pump and air handler - is there a separate model number for the coil and media filter?

I would not have chosen to work with this HVAC guy myself - he's a subcontractor and his communication skills leave much to be desired. But we are at the very end of a long project, and the air handler and ducting is already done, so here we are.

The HVAC system has three major components. In your case it is air handler, coil, and heat pump (condenser). Each have a model number. You want a Carrier coil and not one from a third party. The housing that holds the filter would have a model number, it does not have to be Carrier. You want to understand what type of filter you are getting. You should also get the model number for the thermostat.

Ask a lot of questions and get things in writing.

Thank you! I'm assuming the coil and filter would be located on/around the air handler, is that correct?

I do have the model number for the thermostats. They need to be from a list published by MA.

I've left a lot of this stuff to my GC, who I trust, but this HVAC guy is making this difficult.

The coil is inside the air handler. The filter could be attached to the air handler, or it may be where the main return vent is located.

Got it. I can check on these things tomorrow when I'm at the house. I know the filter is attached to the air handler and when I saw it, it looked like what the internet is telling me is a 4 inch media filter. The air handler and all the ducting are already complete, so this ship has sailed to some extent. I hope they're good.

OK, I heard back from the HVAC guy and he said the reason they quoted the Infinity one rather than the Performance one is that the price difference from Carrier is only $75, so his distributor only stocks the Infinity one and they price it as they would price the Performance one. So that answers that question.

I think in Massachusetts, you can only get the Mass Save rebate, not a separate one from Carrier.

I think we're going to go for it. It sounds like we will probably be happier with the result, which is what really matters.

As Mike said, make sure it's a matching carrier coil (I understand it has already been installed?). Most energy rebates require an AHRI certification number based on the air handler, evaporator coil and outdoor condenser and only certain combinations, from a single manufacturer, are eligible.

Yes, the air handler/coil/filter (and all the ductwork, as this is a retrofit in an old house that did not previously have any of this) were installed a couple months back - they are in an insulated kneewall space and needed to go in before the walls went back up.

I do have the AHRI number (required by MA for the rebate) and plugged it into the AHRI website to check on the certificate. (It doesn't mention a coil though, the only equipment on it is the condenser and air handler.)

The $75 difference between the Performance and Infinity condensers does not make sense. It should be more like $750. It sounds a little fishy but if you think you are getting a fair price on the Infinity then go for it.

I agree it seems odd, but that info came to me directly from the Carrier distributor representative (not our HVAC subcontractor) when I asked him why they quoted the Infinity rather than the Performance. He said when you compare the two stage Performance 16 to the two stage Infinity 16, the price from Carrier is within $75 of each other.

It's hard to know if I'm getting a fair price since I have no basis for comparison and no ability to shop around. The math is also complicated because this decision only came to us after the air handler and ducting were installed and paid for. I believe that all in, cost for the whole system with the two-stage Infinity condenser and Cor integrated controls would be about $13k ($10k after rebates), vs. $7k (maybe with a $1000 rebate available) for the whole system with the single-stage Comfort series condenser and non-integrated controls (meaning with separate thermostats for the heat pump zones vs. the radiator system). So the price difference is substantial, but the rebate makes it seem more palatable...I think?

I agree with Mike...what is model number of the Performance var speed air handler you installed?...the coil is part of the air handler...this would be my choice of outside HP condenser, Mdl 25HCB6, Performance Series 16. I would add a pleated filter media cabinet and matching Performance Wi-Fi thermostat. What size heat strip do you have in air handler?...

IMO

The Performance air handler model we have installed already is FV4CNB003L00.

I asked about the 25HCB6 condenser, but as I said above, they are telling me I am getting the Infinity 16 (25HNB6) for the same price, plus there would be a 3 week lead time for the 25HCB6 because they don't stock it.

The thermostats they quoted (need two, for two zones) are Cor Dual Fuel (TP-WEM01-A).

I believe we do have the filter media cabinet. I'm not sure about the heat strip. This heat pump system is not intended to be used when it's below 32 degrees outside (or whatever the recommendation is for the model we get). We have an oil fueled furnace with hydronic radiators that we are leaving in place for that. Hence the need for dual fuel thermostats/integrated controls.

I certainly would want to know the AHRI matching number for the Infinity condenser paired with a Performance var speed air handler. Ask your dealer. I personally think that's a mistake in the making. What size HP condenser is being quoted? I assume a 2 or 3 ton. You do want a heat strip.

IMO

I do have the AHRI number for this combo - wanted to make sure it existed because we need it for the rebate if nothing else. It's 9160644.

3 ton condenser. I'll ask about the heat strip.

I did verify the number as a certified match. Not what I would do but you are the boss. Follow up on refrigerant lineset, media filter cabinet, and thermostat. Good Luck!

IMO

Thanks! Can you tell me why this isn't what you would do? TBD I am not really running the show here - this is a subcontract, just one part of a big renovation that is almost over and we REALLY want it to end.

Also -- what should I be asking about the lineset and thermostat?

The reason that there wasn't a coil mentioned in the AHRI certification is that it comes standard with that particular air handler (so with the air handler model number specified, the coil is known). The reason Tigerdunes wouldn't use that pairing is that the performance air handler probably doesn't permit the full functionality of the infinity condenser.

If I understand you correctly, the infinity condenser is going to cost $6000-$7000 more than the comfort condenser (less $3000 rebate = your $3000-$4000). The infinity condenser doea not cost $7000 more than a comfort condenser and the performance condenser is not $5925-$6925 more than the comfort condenser. There's some shenanigans going on with the contractor.

FYI: I have two comfort outdoor condensers at my vacation home and I wouldn't do that again - I would definitely go with the two stage performance condenser (or single stage if cost was important) to go with my variable speed FV4 air handlers..

Thanks, that is helpful. Curious, why don't you like the comfort condensers? (We can't get a single stage condenser if we want to be eligible for the $3000 rebate).

Your understanding on pricing is basically correct. We were quoted $7k for the performance air handler+comfort condenser condo (with non-integrated non-dual fuel thermostats provided by me), and ~12000 for the performance air handler+infinity condenser (with integrated dual fuel thermostats provided by them). The ~12k quote does not include some extra cost we would incur for wiring changes we would need for the thermostats, so I added a little extra for that. (I'm fudging the numbers a little bit here, because there is also some amount, I'm not 100% sure how much to allocate, that was covered the bid that was in our original general contract for the whole house reno - this would be our second HVAC related upgrade/change order).

FWIW, the thing about the performance vs. infinity two stage condensers being close in price came to me from the Carrier distributor rep, in writing in an email. Not an ideal venue for lying, but it's possible.

The HVAC contractor told me his cost for the equipment for just the Infinity condenser and the two Cor thermostats (no air handler) would be 5700. So his quote above includes $2800 to install those things, which seems high to me. Our GC agreed with that and suggested maybe it would be more cost effective (and easier) to have the electrician do the thermostats, so he is looking into that.

The reasons I don't like the Comfort condensers is their cheap chinese compressors, and they are noisy (no sound blanket on them and you can't get one from Carrier or Protech to fit properly, only genereric ones that don't realy do anything). There's a reason they are cheap. But a Performance two stage should only be $1000-or-so more.