Looking for a home heat pump system. I need advice.

[Nick Danger]

I'm looking at buying a heat pump for my house. I've had five contractors here, and they each recommend something different.

One guy recommended a single-stage system because of 1960s ducts in the slab can't be altered. He says that the static air pressure will be a problem otherwise. He recommends simple, so there is less to break.
Another guy said that the variable speed could handle the ductwork just fine.
One guy recommended disconnecting the natural gas and using entirely electric heat to supplement the heat pump. He says that a hybrid system is an upsell.
A couple of guys recommended the full bells and whistles, variable everything.
Five contractors recommended five brands of systems. Is Lennox really worth the extra $1000s over York or Heil?
Everyone agrees that I need 3 tons of cooling.
One guy said that he heat pump is good down to -5°F, another only down to 30°F, and a third says down to 20°F.

I'm feeling overwhelmed.

My house is a 1500 sq ft ranch built in 1963. Single level. Albuquerque has about 4000 heating degree days.

 

[fitter30]

Duct work is encase in cement or below grade has anyone inspected them for rust/ holes if there made from galvanized sheet metal. Do you have air conditioning now? What size is the unit? What do you have for heat and size? PNM offers energy checkup ask if it includes a blower door test ( checks to see how tight the house is) and rebates.

 

[jblnut]

This maybe won’t help you make your decision but I have a single 2 ton Fujitsu mini split rated to heat down to 5° F and it has been keeping my farm shop at balmy 64° with it being in the low 30s overnight and low 50s during the day While using around two dollars a day in electricity. It is heating and cooling around 3500 ft.² with an 18 foot ceiling height. Whatever you do, you won’t be disappointed in the efficiency of a mini split.

 

[ericm]

Duct work is encase in cement or below grade has anyone inspected them for rust/ holes if there made from galvanized sheet metal. Do you have air conditioning now? What size is the unit? What do you have for heat and size? PNM offers energy checkup ask if it includes a blower door test ( checks to see how tight the house is) and rebates.

If you can get that for free, take it! I paid $600 for an efficiency study seven years ago and it was worth it. I found out what cost effective things I could do to improve comfort and efficiency.

If you can get the heat pump unit details from the HVAC contractors you can look up the specs yourself. https://ashp.neep.org

 

[The Metric System]

He recommends simple, so there is less to break.

This is not consistent with the reality of technology level vs reliability in home heat pump systems.

Variable capacity compressors and fans make an enormous positive difference in long-term system life by reducing stop/start circuits and keeping the compressor closer to it's ideal operating range as conditions change.

I have been in the AC/refrigeration industry for 25 years and precisely worked at a major T1 supplier and had access to all their return/failure/warranty numbers. My general recommendation for home central air/heat pumps is an appropriately-sized Goodman unit with a variable-speed scroll compressor, installed by the best tech in town.

 

[Nick Danger]

This is not consistent with the reality of technology level vs reliability in home heat pump systems.

Variable capacity compressors and fans make an enormous positive difference in long-term system life by reducing stop/start circuits and keeping the compressor closer to it's ideal operating range as conditions change.

I have been in the AC/refrigeration industry for 25 years and precisely worked at a major T1 supplier and had access to all their return/failure/warranty numbers. My general recommendation for home central air/heat pumps is an appropriately-sized Goodman unit with a variable-speed scroll compressor, installed by the best tech in town.

Thank you. That helps.

No one quoted Goodman. I got Carrier, York, Coleman, Lennox, and Heil. I read online that Coleman is a bargain brand which I should avoid, which works for me because I didn't like the sales rep who did the estimate.

Duct work is encase in cement or below grade has anyone inspected them for rust/ holes if there made from galvanized sheet metal. Do you have air conditioning now? What size is the unit? What do you have for heat and size? PNM offers energy checkup ask if it includes a blower door test ( checks to see how tight the house is) and rebates.

Duct work is below grade, probably encased in cement. They have not been inspected for a while. But I'm stuck with them. There is no space between the roof and ceiling for ductwork. The ceiling and roof are both nailed to the the same beams.

I currently have a swamp cooler and am converting to refrigerated air.

This maybe won’t help you make your decision but I have a single 2 ton Fujitsu mini split rated to heat down to 5° F and it has been keeping my farm shop at balmy 64° with it being in the low 30s overnight and low 50s during the day While using around two dollars a day in electricity. It is heating and cooling around 3500 ft.² with an 18 foot ceiling height. Whatever you do, you won’t be disappointed in the efficiency of a mini split.

I got a couple of estimates for mini splits. They aren't a good match for the house.

 

[theoldwizard1]

One guy recommended disconnecting the natural gas and using entirely electric heat to supplement the heat pump.

Run away from this guy ! Electric supplemental heat will put you in the poor house fast !!

One guy said that he heat pump is good down to -5°F, another only down to 30°F, and a third says down to 20°F.

This where things get really confusing ! Assuming you are not going geothermal (wells or buried loops) different systems from different manufactures have different low temperature capabilities.

Worse, when you try to read the specs you will find that different manufactures test and report results differently

I would consider abandoning the current duct work and installing a couple of high wall mounted air handlers. Depending on how many rooms you have and how they are laid out you may only need 2 or 3. A floor plan, with room sizes, would be helpful.

 

[nadogail]

The quality of the installation is, IMHO, more important than who makes the equipment.

You will see the Installer maybe once, your Service Technician is very important.

 

[danski0224]

I'm looking at buying a heat pump for my house. I've had five contractors here, and they each recommend something different.

One guy recommended a single-stage system because of 1960s ducts in the slab can't be altered. He says that the static air pressure will be a problem otherwise.

There is some truth here. If the system is oversized, or if the ductwork is too small for a properly sized system, a variable speed motor WILL compensate- to a point. Then your operational costs will go up and motor life will go down.

He recommends simple, so there is less to break.

Also some truth here. However, nothing is simple any more.

For the most part, control boards are well engineered to get past the *up to* 10 year warranty if the equipment is registered. These boards are commodity items and not fragile pieces of glass. All equipment has some sort of control board or two or thee in it now. No escaping it. They can be taken out by power surges or cheaper component substitution at the place of manufacture. The first one you can mitigate with surge protection devices.

Another guy said that the variable speed could handle the ductwork just fine.

It will, until it doesn't.

One guy recommended disconnecting the natural gas and using entirely electric heat to supplement the heat pump. He says that a hybrid system is an upsell.

Bad idea.

A couple of guys recommended the full bells and whistles, variable everything.

I would do the same.

Five contractors recommended five brands of systems. Is Lennox really worth the extra $1000s over York or Heil?

No, if the equipment specs are otherwise similar. You can't compare on price alone.

Everyone agrees that I need 3 tons of cooling.

How? Based upon what you got now? Or did someone actually do a load calculation?

One guy said that he heat pump is good down to -5°F, another only down to 30°F, and a third says down to 20°F.

How do they know this?

I'm feeling overwhelmed.

My house is a 1500 sq ft ranch built in 1963. Single level. Albuquerque has about 4000 heating degree days.

Built in 1963 = ****** insulation. Roof - ceiling combination = ****** insulation, no matter when it was built unless the cavities are filled with spray foam or well fitted solid foam.

Like it or not, you need a load calculation. You can spend $50 for HVAC-Calc and get a single use license. Not ACCA approved, but it works and the learning curve is shallow.

Most heat pumps lose capacity as temperature drops. Only the high end stuff like Mitsubishi Hyper Heat or Bosch IDS Ultra does not (within limits). Bosch IDS Ultra claims to output full BTU capacity down to 3º F and to continue to initiate a call for heat down to -13ºF. This information is in the manufacturer specifications, which includes indoor coil match.

Other manufacturers offer inverter type systems and they are as much or more than Bosch and do not have the same features.

You need the load calculation to figure two things:

• Balance point: this is the point when the heat pump will no longer heat your space. Load calculation results and manufacturer data are used to figure this number in a balance point calculator.
• Economic balance point: this is when your utility costs make the use of the heat pump not economically viable. If you have low natural gas costs and somewhat reasonable electric rates, then an example economic balance point might be 50ºF. You do not know this without doing the math. The math changes as utility costs change.
• The "economic balance point" is put into the dual fuel thermostat as "compressor lockout temperature".
• If you are not provided with a balance point and economic balance point, it is a guess as to whether or not the system will work, and it can easily cost you way more to operate it.

Your ductwork needs to be evaluated as part of the load calculation.

Improving insulation can reduce equipment size and therefore reduce or eliminate ductwork problems. Airflow and therefore ductwork size is dictated by equipment size.

If you are chasing a tax incentive, the equipment has to have an AHRI matching number. A larger indoor coil can be put on a Bosch system to get more heat output, but there will not be an AHRI match combination for that system... and the ductwork has to be there to support the airflow. Bosch has easy to read tables that show outdoor+indoor+furnace combinations and capacities.

Whatever you do, it is IMPERATIVE that you register the equipment online for that "free" 10 year parts warranty. The inverter board in the outdoor unit is 4 figures to buy it.

I would also STRONGLY recommend surge protectors at the furnace and at the outdoor unit.

Disclaimer: I have a 2 stage heat pump (but not Bosch) in my house with a VS 2 stage gas furnace. I can do a load calculation. I can figure the balance points. I have installed Bosch. I know what I am talking about.

Good luck.

 

[Nick Danger]

There is some truth here. If the system is oversized, or if the ductwork is too small for a properly sized system, a variable speed motor WILL compensate- to a point. Then your operational costs will go up and motor life will go down.

Also some truth here. However, nothing is simple any more.

For the most part, control boards are well engineered to get past the *up to* 10 year warranty if the equipment is registered. These boards are commodity items and not fragile pieces of glass. All equipment has some sort of control board or two or thee in it now. No escaping it. They can be taken out by power surges or cheaper component substitution at the place of manufacture. The first one you can mitigate with surge protection devices.

That means a dead control board won't destroy the system, the way it does on a refrigerator. That makes me feel better.

It will, until it doesn't.

Bad idea.

I would do the same.

No, if the equipment specs are otherwise similar. You can't compare on price alone.

How? Based upon what you got now? Or did someone actually do a load calculation?

One guy did a 3-minute load calculation.

How do they know this?

I have no clue how they know what the minimum outside temperature is.

Built in 1963 = ****** insulation. Roof - ceiling combination = ****** insulation, no matter when it was built unless the cavities are filled with spray foam or well fitted solid foam.

I had the roofing company add R5 rigid foam insulation when I bought a TPO roof. It was a huge improvement.

Like it or not, you need a load calculation. You can spend $50 for HVAC-Calc and get a single use license. Not ACCA approved, but it works and the learning curve is shallow.

I performed a free online load calculation a few years ago and came up with 3 tons. It was a couple pages long, pretty detailed.

Most heat pumps lose capacity as temperature drops. Only the high end stuff like Mitsubishi Hyper Heat or Bosch IDS Ultra does not (within limits). Bosch IDS Ultra claims to output full BTU capacity down to 3º F and to continue to initiate a call for heat down to -13ºF. This information is in the manufacturer specifications, which includes indoor coil match.

Other manufacturers offer inverter type systems and they are as much or more than Bosch and do not have the same features.

You need the load calculation to figure two things:

• Balance point: this is the point when the heat pump will no longer heat your space. Load calculation results and manufacturer data are used to figure this number in a balance point calculator.
• Economic balance point: this is when your utility costs make the use of the heat pump not economically viable. If you have low natural gas costs and somewhat reasonable electric rates, then an example economic balance point might be 50ºF. You do not know this without doing the math. The math changes as utility costs change.
• The "economic balance point" is put into the dual fuel thermostat as "compressor lockout temperature".
• If you are not provided with a balance point and economic balance point, it is a guess as to whether or not the system will work, and it can easily cost you way more to operate it.

I wonder if the guys heard that I have solar panels and then stopped worrying about electric costs. I still have to pay for any electricity in excess of what my solar system generates, which is equal to what I use in a year without this new HVAC.

Your ductwork needs to be evaluated as part of the load calculation.

Improving insulation can reduce equipment size and therefore reduce or eliminate ductwork problems. Airflow and therefore ductwork size is dictated by equipment size.

If you are chasing a tax incentive, the equipment has to have an AHRI matching number. A larger indoor coil can be put on a Bosch system to get more heat output, but there will not be an AHRI match combination for that system... and the ductwork has to be there to support the airflow. Bosch has easy to read tables that show outdoor+indoor+furnace combinations and capacities.

Whatever you do, it is IMPERATIVE that you register the equipment online for that "free" 10 year parts warranty. The inverter board in the outdoor unit is 4 figures to buy it.

I would also STRONGLY recommend surge protectors at the furnace and at the outdoor unit.

Disclaimer: I have a 2 stage heat pump (but not Bosch) in my house with a VS 2 stage gas furnace. I can do a load calculation. I can figure the balance points. I have installed Bosch. I know what I am talking about.

I got my EPA refrigeration certification twenty five years ago, and I've forgotten almost all of it.

Good luck.

Thank you for your lengthy and detailed post.

 

[fitter30]

Thank you. That helps.

No one quoted Goodman. I got Carrier, York, Coleman, Lennox, and Heil. I read online that Coleman is a bargain brand which I should avoid, which works for me because I didn't like the sales rep who did the estimate.



Duct work is below grade, probably encased in cement. They have not been inspected for a while. But I'm stuck with them. There is no space between the roof and ceiling for ductwork. The ceiling and roof are both nailed to the the same beams.

I currently have a swamp cooler and am converting to refrigerated air.


I got a couple of estimates for mini splits. They aren't a good match for the house.

Then you don't have a ducted return air. Trying to push 1200 cfm with to small of duct will make the air noisy. Take a look at this system.

 

[Nick Danger]

Then you don't have a ducted return air. Trying to push 1200 cfm with to small of duct will make the air noisy. Take a look at this system.

Good question. I do have ducted return air in a drop ceiling in the hallway. I had new ductwork installed ten years ago.

 

[danski0224]

I wonder if the guys heard that I have solar panels and then stopped worrying about electric costs.

There is truth to this.

But one still needs to know the balance point. It is possible that a "3 ton" condenser will run out of steam in heating mode. Even a Bosch IDS will only deliver a maximum of 36k btu of heat (for that size unit) down to 3° F. If you need more than 36k btu of heat at say 20° F, it won't work.

The economic balance point would be harder to pin down given "free" electricity. Probably would be limited by the temperature balance point in a heating climate unless the building is super insulated and sealed.

 

[The Metric System]

No one quoted Goodman. I got Carrier, York, Coleman, Lennox, and Heil. I read online that Coleman is a bargain brand which I should avoid, which works for me because I didn't like the sales rep who did the estimate.

I like Goodman because:

• They're inexpensive
• They've well-designed and robust
• They are available with (IMO) the right level of techology, and have genuinely useful things like variable-speed compressors without the low-value high-cost features that come with the premium brands
• This is the big one: They sell to anybody, even homeowners, so you don't need to go through a distributor or reseller to get your equipment. This makes it easy for you to comparison shop and keeps your costs down by avoiding opaque pricing or markup by the middleman.

I wouldn't avoid another big brand if you get a deal with them, but Goodman is usually the best-cost option.

I would avoid any newer international brand without a large established presence in the US. This is not because their equipment is bad, but rather because it makes parts and service more difficult in the future. In some cases even the refrigerants used are relative oddballs in the US, which means techs won't have them on their truck or will have to special-order them etc.

 

[JeepYJ]

Run away from this guy ! Electric supplemental heat will put you in the poor house fast !!

He’s in Albuquerque where winter lows are typically in the 20s. A heat pump can keep his house comfortable without supplemental heat.

 

[danski0224]

A heat pump can keep his house comfortable without supplemental heat.

If it is sized properly and the balance points are known.

 

[JeepYJ]

If it is sized properly and the balance points are known.

Of course. That’s not a reason to run away from the guy who recommended supplemental electric heat. It’s the most sensible solution in my opinion. No reason to mess with gas lines and venting and a propane tank (if not on natural gas) for supplemental heat that may never be used.

 

[danski0224]

Given 36k btu AC, I'm assuming that won't cover heating, even if the heat pump will output full btu's under 17°F....

But, guesswork without numbers.

 

[pembol]

I'm looking at buying a heat pump for my house. I've had five contractors here, and they each recommend something different.

One guy recommended a single-stage system because of 1960s ducts in the slab can't be altered. He says that the static air pressure will be a problem otherwise. He recommends simple, so there is less to break.
Another guy said that the variable speed could handle the ductwork just fine.
One guy recommended disconnecting the natural gas and using entirely electric heat to supplement the heat pump. He says that a hybrid system is an upsell.
A couple of guys recommended the full bells and whistles, variable everything.
Five contractors recommended five brands of systems. Is Lennox really worth the extra $1000s over York or Heil?
Everyone agrees that I need 3 tons of cooling.
One guy said that he heat pump is good down to -5°F, another only down to 30°F, and a third says down to 20°F.

I'm feeling overwhelmed.

My house is a 1500 sq ft ranch built in 1963. Single level. Albuquerque has about 4000 heating degree days.

We just built a house in Colorado front range, so similar to Albuquerque, but maybe 5-6F colder in the winter. We ended up with a ground source heat pump for the house and an air source mini split heat pump for the detached garage. Both work fine without any sort of backup heat, so your house would be fine without backup. That said, resistive heat coils are cheap to install, so it is worth including these, even if they are just in case of a maintenance issue with the heat pump.

We talked to a bunch of HVAC contractors before deciding on the geothermal one, and the hardest part was finding a contractor who was actually well versed in modern heat pumps and didn't just insist that whatever brand they normally sell was the best option. The ones who said they stop working at 20 or 30F definitely don't know what they are doing, or are selling the wrong equipment.

It may be worth getting a quote for a mitsubishi ducted minisplit system from a mitsubishi diamond certified dealers. These are the gold standard in cold climate heat pumps, and work better than most of 'domestic' hvac brands.

 

[danski0224]

We ended up with a ground source heat pump for the house and an air source mini split heat pump for the detached garage. Both work fine without any sort of backup heat, so your house would be fine without backup.

If both of those are inverter compressor systems, they do not work the same as a "regular" system.

 

[danski0224]

The ones who said they stop working at 20 or 30F

The heat output from a non inverter system is not the same as a "regular" system.

It comes down to equipment specs.

 

[pembol]

The heat output from a non inverter system is not the same as a "regular" system.

It comes down to equipment specs.

Absolutely - specifying appropriate equipment is part of the job. If you want to heat with a heat pump in Alburquerque, then an inverter systems would probably be the right equipment. The problem is most HVAC contractors just sell what ever brand they are familiar with, regardless if it is the appropriate equipment for the application.

Our neighbors experienced this first hand - their builder uses one HVAC contractor, and they only use Carrier, as a result they have an inappropriate heat pump that costs them a fortune to run in the winter because is does use backup resistive heat.

 

[dscheidt]

If both of those are inverter compressor systems, they do not work the same as a "regular" system.

It’s 2025, inverters are perfectly normal. Anyone recommending an old fashioned non variable speed compressor to someone interested in heat is behind the times.

 

[Nick Danger]

I chose to buy an inverter compressor, a gas furnace, and a variable fan.

Thank you all for your advice.

 

[danski0224]

It’s 2025, inverters are perfectly normal. Anyone recommending an old fashioned non variable speed compressor to someone interested in heat is behind the times.

There is a very significant wholesale price difference between an "old fashioned" single stage compressor and a upper end variable speed variant. Even within a variable speed product line, there is a significant price difference from an "18 SEER" model to a model with extended low temperature heating performance.

The ideal solution may not be affordable to the customer.

 

[danski0224]

their builder uses the lowest bid HVAC contractor,

Fixed it for you.

And until homebuyers are interested in what is beneath the painted drywall, nothing will change.

 

[danski0224]

I chose to buy an inverter compressor, a gas furnace, and a variable fan.

Thank you all for your advice.

Don't leave us hanging on the important details like equipment, scope of work and of course the price...

 

[DGersic]

Economic balance point: this is when your utility costs make the use of the heat pump not economically viable. If you have low natural gas costs and somewhat reasonable electric rates, then an example economic balance point might be 50ºF. You do not know this without doing the math. The math changes as utility costs change.

This is a great point, and bears repeating for emphasis. Since I have been tracking mine, the economic cutoff point varies a lot more than I would have expected it to. And because natural gas is significantly cheaper than electricity here and now, my heat pump isn’t getting much use for heating.

If the guy selling you a dual fuel system isn’t discussing things like cutoff points and the relative costs of the fuels to be used, I’d suggest shopping elsewhere.

And the guy suggesting electric strip heat needs to be ejected immediately.

 

[DGersic]

One guy said that he heat pump is good down to -5°F, another only down to 30°F, and a third says down to 20°F.

They are probably quoting you the manufacturer specs that the heat pump will run and produce heat. Just because it will run, doesn’t mean that it’s running with any efficiency.

There is a downward arcing curve, if you graph efficiency vs outdoor temperature. Different heat pumps will have different curves, but all will have some fall off of efficiency if you’re trying to extract heat from outside air to move it inside.

At some outdoor temperature, you’re better off using a different heat source. If your area never reaches that temperature, a heat pump only may make sense. If it rarely happens, like once every five to ten years, then something inefficient like electric strip heat maybe makes sense, because you won’t use it enough to care how inefficient it is. If you can reasonably expect lower temperatures, a duel fuel system with a heat pump and natural gas furnace may make the most of what’s available to you.

You need to look at the economics of the heat sources, find the cutoff point for your local situation, then make a guess as to how those economics are going to go over the expected life of the system.

 

[danski0224]

If the guy selling you a dual fuel system isn’t discussing things like cutoff points and the relative costs of the fuels to be used, I’d suggest shopping elsewhere.

The big problem here has a couple of major bullet points

• The balance point can't be figured without a load calculation
• The economic balance point can't be figured without:
  • a load calculation
  • utility rates
  • published manufacturer data that gives the heating capacity for a given fan (furnace or air handler) matched to a given indoor coil matched with a specific outdoor unit
  • This whole exercise can get wonky for someone that has "free" electricity like solar
• There may be some ways around the math with app based calculators that use regional weather data and utility bills, however I have not used any of those.
• Based just on threads in this small forum, it seems to be:
  • extraordinarily difficult to get a HVAC contractor to perform a load calculation
  • More difficult to get someone to pay for one
• The economic balance point is needed for the compressor lockout temperature setting in the thermostat, and the homeowner needs to know this.

And the guy suggesting electric strip heat needs to be ejected immediately.

Not necessarily, they have their place. I would 100% recommend heat strips for someone that is finishing a basement in my area, vs a gas furnace.

 

[danski0224]

They are probably quoting you the manufacturer specs that the heat pump will run and produce heat. Just because it will run, doesn’t mean that it’s running with any efficiency.

There is a downward arcing curve, if you graph efficiency vs outdoor temperature. Different heat pumps will have different curves, but all will have some fall off of efficiency if you’re trying to extract heat from outside air to move it inside.

This is all provided in the manufacturer cooling and heating data charts... which of course must be read.

The "selling technician" (technician used very loosely) at a residential HVAC place isn't going to be busting out these tables, nor is the homeowner going to pay attention for more than 2 seconds before the eyes glaze over.

 

[4xdog]

...It may be worth getting a quote for a mitsubishi ducted minisplit system from a mitsubishi diamond certified dealers. These are the gold standard in cold climate heat pumps, and work better than most of 'domestic' hvac brands.

I just had 3t (36k BTU) and 2t (24k BTU) Mitsubishi P-series Hyper-Heat ducted minisplits installed in my flat-roof house a little south of Santa Fe, replacing two 20yo Goodman package units running on propane. The Goodman units were working fine (although propane is expensive, even as I keep low set points in the house) but as they had to come off the roof anyway for roof replacement it seemed prudent to do the upgrade.

So far (less than 2 weeks as nightime temperatures are just starting to call for heat) are good. Completely quiet and effortlessly maintaining setpoints. It's nice to be divorced from propane for heat in the house.

 

[u2slow]

Also in a 1600sqft rancher-ish home.

I wish my central system had a variable speed fan, and also worked better when it's cool outside (5-15°C).

 

[DGersic]

The "selling technician" (technician used very loosely) at a residential HVAC place isn't going to be busting out these tables, nor is the homeowner going to pay attention for more than 2 seconds before the eyes glaze over.

Admittedly, I’m weird. I read all of the manuals for the furnace, heat pump, and two zone control system. What I want from a “sales technician” would indeed glaze over most people.

 

[DGersic]

Not necessarily, they have their place. I would 100% recommend heat strips for someone that is finishing a basement in my area, vs a gas furnace.

They do have a place, but recommending taking out natural gas and replacing it with heat strips?

I guess this could be tilted by the later comment that OP has solar electricity, so effectively “free” to run electric heat strips, but OP also seems to indicate that his solar capacity is just enough to meet current house needs, probably then not enough to run the heat strips, especially when it’s cold enough to need them.

 

[u2slow]

If I had nat gas available on my street, I would want to be able to use that for backup heat - even if it's a fireplace (or 2) that can contribute for the air-handler to circulate.

What happens now is my electric use is driven into the higher 2nd-tier rate every billing cycle.

 

[JunkBonds]

And the guy suggesting electric strip heat needs to be ejected immediately.

Total bunk.

The heat strips are "just in case". That means not expecting to use them.

My Mitsubishi HP is good to -30c / -22f.

In my area it rarely gets to -25c. In my life I have not seen it colder here.

 

[pcmeiners]

Realize the OP purchased a variable unit. The only reasons at this point of a single stage unit is either a mechanical fitting issue but profit margin is the main goal. At this point warehouses are dumping shelved single stage cheap so they do not have to get a dumpster for them. If offered a single stage split find another company.

 

[HoosierBuddy]

Total bunk.

The heat strips are "just in case". That means not expecting to use them.

My Mitsubishi HP is good to -30c / -22f.

In my area it rarely gets to -25c. In my life I have not seen it colder here.

You are only partially correct.

The heat strips come in when it gets cold enough outside that the heat pump can't keep up.

The heat strips also come in if the thermostat has been setback and is then cranked back up.

The heat strips also come in when and if the heat pump outdoor unit fails during the winter.

Point being, even if you live in a zone where the heat pump can keep up all the time, with no help from the extra resistance "emergency" or gas furnace "backup" you still face running the emergency strips for recovery from setbacks and if/when the heat pump fails or requires serviceing.

As the resistance strips increase the cost to produce a BTU by the COP of the outdoor unit (like 5 times?) this can turn a $300 bill into a $1500 bill if due to unit failure. Seen it many times. And although you and the rest of us GJ guys are going to catch the fact the heat pump portion of the unit has failed pretty quick, and get it fixed, MOST people don't notice it until they get their power bill. Which means they already have used another 10 days of power before they even get the HVAC guy called.

The setback issue is more insidious. I had a church call me begging for me to run NG to them because of the $5000 monthly power bills they were seeing. It was way too far for us to run (miles) but I talked them through the fact that as they were trying to save money by making sure all of the church's heat pumps were set back every night and on Saturdays, they were actually increasing their power bills not reducing them because every morning they'd come in and crank the t-stats back up and force the emergency strips to come in for recovery.

Glad your heat pump is working well for you.