The DAIKIN DM96VC includes support for the ComfortNet Control System which you don't want. I'd ask about the DAIKIN DM96TN which only supports a standard, two-stage thermostat and is less expensive.

However, the the DAIKIN Corp sells products under the DAIKIN, Goodman, and Amana brands. The Goodman GM9C96 is the same as the DAIKIN DM96TN and may be less expensive because it's a "less-prestigious" brand so I'd check out that model.

Likewise the Goodman GSZS6 is the same as the DAIKIN DZ6VS and also may be less expensive.

Of course, you must confirm compatibility between products.

Thermostat I have and really like: Honeywell THX321WFS2001W T10 Pro Smart Thermostat

That's basically a Goodman two stage furnace with a Daikin minisplit-type inverter heatpump outdoor unit. My daughter has a similar setup. It works well but was VERY expensive compared to a comparable Goodman system..

Having said that, the system will live or die by the quality of the installer. You pays your money, you takes your choice!

hello sktn77a

ty for the comment.

just fyi as we were doing research we did learn:

n 2012, Goodman was purchased by Daikin Industries, Ltd and became a member of Daikin Group. Daikin is a global Fortune 1000 company and is a worldwide leader for residential and commercial heating, ventilation and air conditioning.

i totally agree with you -- quality of technicians is so critical.

Hi, Rhonda,

The system recommended by your contractor is a dual-fuel or hybrid heating system. It's a good option. Since you have limited availability of local HVAC contractors, I'd lean toward their recommendation. You want to choose equipment that they are familiar with and possibly stock parts for.

Daikin is a world leader in the HVAC industry. They manufacture equipment just outside Houston, TX which is located (I think intentionally) close to Katy, TX.

What questions should we be asking or what else should we consider at this time?

• Ask about a labor warranty after the first year
• Ask if the line set will be replaced
• I don't recall what you currently have, but I would want a 4 inch media filter
• Ask what is the the cost of annual preventative maintenance and how often it is required

I seem to recall you had the thermostat wiring replaced during one the your attempts to fix the problem with your Carrier furnace. Ask the installer if the current wiring is what the manufacturer recommends fir a new installation. Ask the installer to check the signal levels (assuming he knows how to do that) at each end of the thermostat wiring. The wiring from the furnace to the heat pump should also be replaced if there is any doubt about it.

I would not worry about buying equipment using R410a refrigerant. The more climate friendly refrigerants are flammable and cannot be installed in residential homes under the current fire building codes. The American Innovation and Manufacturing (AIM) Act approved by Congress in 2020 authorizes the EPA to begin the phase out of R410a. However the neither Congress or the EPA have come up with a solution how to make the installation of a flammable refrigerant safe in a residential home. I would think after four years the fire prevention solutions have been discussed by the people who write the building codes. I suspect what the code officials believe what will be required will be expensive and not practical for many homes.

"The more climate friendly refrigerants are flammable and cannot be installed in residential homes under the current fire building codes." . A number of states have already approved the use of A2L refrigerants in their residential building code including Oregon, Florida, Washington, and North Carolina. The ICC, which produces the International Residential Code, has language in the 2024 IRC allowing the use of A2L refrigerants. The expectation is that most, if not all, states will have their building codes modified prior to January 1, 2025.

The bottom line is that the phase down of R410a and the transition to other refrigerants isn't the end of life on earth as we know it despite the fear mongering.

Thank you @sktn , @charlesRosshomes , @AustinAirCompanie and @MikeHome for the helpful responses.

@mike_home ... what is the line set you mentioned (and why would it need to be replaced) ... and ... what is a 4 inch media filter (and why is this suggested?). I'd just like to understand what I'm asking about!

All: Appreciate the followup questions for my local installer:

• is there a comparable Goodman (or other) brand that he has experience installing and servicing that might do the job and be less expensive?
• What is the labor warranty after the first year
• What is the the cost of annual preventative maintenance and what is required
• Will the line set will be replaced
• Will it have a 4 inch media filter?
• Is my current wiring what the manufacturer recommends for a new installation.
• Request that he check the signal levels at each end of the thermostat wiring, and request that the wiring from the furnace to the heat pump be replaced if there is any doubt about it.
• What happens once the R410a refrigerant is phased out --

I'll be back in touch with any followup questions. THANKS AGAIN.

I like you are preparing your list of questions for the contractor. Take good notes.

Here is an expample of a 4 inch filter: Bryant / Carrier Genuine OEM MACPAK Filter FILXXCAR0016 The filter is 4 inches thick. They are more expensive than a 1 inch thick filter but they last much longer and have less air flow resistance.

The line set is the pair of copper tubing connecting the outside condenser and the indoor coil. Here is a good reference photo (click to enlarge):

The line set will be covered with insulation. If the line set was replaced 12 years ago when the Carrier system was installed, and it is the proper diameter for the the Daiken, then I feel a replacement is not necessary. But if it is the original line sent from the previous equipment which used R22 refrigernant, then I suggest you replace it. Follow the recommendation of the installer.

The photo has other items to put on your question list. This includes the electric disconnect (there are code requirements for this), the distance the condenser will be installed from the house, and the pad which the condenser will sit on. This installation has a set of short snow legs. I suggest having the condenser sit higher than the expected snow height.

• Request that he check the signal levels at each end of the thermostat wiring, and request that the wiring from the furnace to the heat pump be replaced if there is any doubt about it.
• What happens once the R410a refrigerant is phased out --

While the thermostat wire doesn't hurt to be tested in my professional opinion even if the thermostat wire is replaced doesn't mean you won't have problems with a sensitive DC pulse signal some time later. Reason is that "things happen". Mice get in sometimes and like to chew things, older wires with older signals as in AC current, the worst that can happen is it develops a short and blows the fuse or worse the transformer. So an AC (alternating current) signal 24v is simple and much more reliable.

In order for a short to occur you need hot wire touching ground within the wiring of the thermostat. A sensitive DC pulse signal could get interrupted due to interferrence of the signal if the outter jacket of the wire is chewed / rubbed off. This isn't to suggest what will happen, only that it could.

The fault code(s) could be due to the wiring, could be due to the equipment, parts etc and so on. The wiring is merely a small part of the overall "network" that is used to operate the AC / Heat pump. It's great when it works, but these are unnecessary bells and whistles for someone looking for simplicity, not to mention reliability. When I say this I am talking about over the course of the life of the equipment. It's not to suggest there will be any problems with a new install, they do happen but it's rare. Just stating what is more reliable.

---------- refrigerant phase outs ------------

R410a phase out -- how I deal with it: It only effects you if you have a refrigerant related problem in which refrigerant is needed to correct it: Refrigerant leaks in a part like Evaporator coil is the most common anywhere from 3 to 8 years typically. If you're really lucky 10 years or so. Component failure like Compressor? For this Daikin fit heat pump you're considering a compressor failure would likely be the reason for invoking warranty equipment replacement, any refrigerant for that should be minimal.

Worse case refrigerant: as in we don't know how expensive R410a will be (prices change all the time), nor currently how much the new replacements will be as in like buying all new equipment again because the refrigerant is cheaper. R410a equipment is not compatible with the new refrigerants so if the decision comes to switching refrigerants you're looking at new equipment again. You can't just take any equipment and stick any refrigerant in it an expect it to work properly. So the worst case would be that R410a price goes up so much that it's making you think that money would be better spent on new equipment again. (it's all about cost really, no other reason except to feel marginally better about climate aspects.)

R32 equipment: R32 refrigerant no mix n match. R454b equipment: R454b refrigerant no mix n match. So every time the refrigerant changes the equipment is going to change as well / unless they deem an alternative refrigerant is proper for xyz machine.

But we went thru this refrigerant debacle with R22 and manufacturers were voiding equipment warranties for those who were using alternative refrigerants. So there's no saftey in that. You essentially do it / don't do it at your own risk. I doubt this changes any moving forward, as right now with the R454b PFAS debacle they are claiming exemptions because there isn't anything else.

There's disclaimers in all warranty literature about the use of refrigerants since R22 Freon even, so if this isn't performed to spec, you'll void the manufacture warranty.

Once again, TY to everyone who was kind enough to offer us advice to ask good questions to the HVAC company that has offered us the proposal for the new system

Good Luck with what ever you decide Steve.

The challenge forward is only to get more dicey as we head toward 2035/2036 as this will begin a new refrigerant phase out, phase down period for R32 & R454b as the goal for the US is to get below 350 GWP (Kigali Ammendment terms) and neither of these replacement refrigerants hit that target. (both of them are above it.)

Your ductwork’s ability to handle airflow at delivered temperatures must be compatible with the heat pump equipment you plan to install. If your ductwork is sized for a gas furnace, you might have problems with the lower temperatures delivered by a heat pump.

IMPO

SR

The existing ductwork should not be a problem for the proposed hybrid (combination heat pump with gas furnace back up) system provided the system is properly sized. If outdoor conditions are extreme, the gas furnace will kick on, replicating the function of the OP's existing gas furnace system.

Agreed, however, for maximum efficiency with an electrified system (cold climate heat pump), the ductwork should be designed for air volume at HP supplied (low) temperatures at as close to design conditions as possible for both efficiency and comfort.

IMPO

SR

I'd live with the limitations of the existing duct work system. It may result in extended run times in heat pump heating mode under some outdoor conditions. When it's too cold outside for the heat pump system to maintain comfortable indoor conditions , the OP has the option to switch over to gas heat which should perform comparably with their existing gas-only heating system.

Hello everyone who sent us great comment!!

we were late to reply because we were drivng home from Fla!!!

we have read all comments and reviewed almost all points with the owner of the BVAC company we use. we spent over 1 hour on a call and your comments really gave us an educated lsit of question>

we will advise all of any more questions and so much appreciate the info...

Diiken system is a piece of junk to us.

temperature varies 7 degrees. too cold to too hot; alternating. I wish I had bought Mitsubishi HVAC.

nvt951: "Diiken system is a piece of junk to us...temperature varies 7 degrees."

This is not a helpful comment as Daikin manufactures hundreds of different products. Perhaps its thermostat is defective or incorrectly configured. My Honeywell Pro 10 thermostat (for example) which controls a heat pump supports a configurable temperature swing anywhere from 0.5 to 3.5 degrees from setpoint.

Replacing the Carrier makes sense given service issues. Daikin gas furnace with heat pump fits propane, ducts, and cold CT winters, with simpler controls. Before installing, I’d review the Daikin RZQ24TAVJU installation manual on acmanuals to confirm wiring, defrost, and service specs so future maintenance stays straightforward.