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Heat Pumps

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oshkosh

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A few years ago I bought my first house (built in the 90s) with all original mechanicals still chugging along. We have oil that fuels both the furnace (forced hot air) and hot water heater using oil burners, in addition to central A/C so the whole house is already ducted. I would like to upgrade all of this, preferably moving entirely away from oil. We are on borrowed time especially with the ol’ Superstor water heater ready to burst at the seams.

I see there are loads of incentives (energizeCT rebates + loans, federal tax credits) for heat pump units and hot water heaters, I just don’t know how well these perform in our climate and whether these are suitable replacements here.

I spoke to a couple HVAC tech’s who both mentioned that heat pumps need a backup heat source for cold days (<30 degrees F), yet I have seen units in my limited research that are rated for performance down to -15F.

I can recite the career stats of Ruslan Inyatkin on demand, but I simply don’t know jack about boilers, burners, furnaces, coils and that speak. Has anyone had a similar experience converting over these systems and can offer any helpful advice?
 
I've been researching also, and 30* doesn't seem very good. I thought they were OK for much closer to 0*, but I'd certainly trust the HVAC pros before whatever I read.
 
I would call a company that installs the units that go down to -15. See what they will put in writing. The “30 degree rule“ was what I was familiar with but spoke with someone a few years ago that said they perform much better now in cold weather
 
My only contribution to this thread is that I just had a repair done on my furnace. The secretary who handled my payment recognized from my email name that I am a UConn fan. She's a Tarheel fan and wasn't too pleased that we womped her team. I'll have to watch my credit card for unusual purchases.
 
.-.
We installed a Navien propane fueled tankless water heater because we already had propane tanks in the backyard and it is awesome. It is attached to the wall and takes up very little space. We got rid of a hot water heater, an old oil furnace which was on its last legs, and an oil tank. Here is a photo I found online which is pretty much how ours looks.

navien.jpeg
 
NJHusky said:
Geothermal systems can be quite pricey
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Daughter in Mass just did a lot of work on their very old house. Were going to do geothermal, but were moved to air heat pumps and existing oil burner as backup. Their contractor said the new air heat pumps were good enough for Boston area weather and much cheaper than the geothermal.
 
If you are doing an electric heat pump there is something called a heat pump helper that runs on propane. Saw it in an LP industry magazine. I'm not in that business, just happened to remember seeing this.
propane.com

A Hybrid Heat Pump Solution, Powered by Propane

An air-handler-installed Heat Pump Helper™ moves hot water from the propane tankless water heater across newly installed hydronic coils to create hot air that is then blown through the existing ductwork to heat the home.
propane.com propane.com
 
ctchamps said:
My only contribution to this thread is that I just had a repair done on my furnace. The secretary who handled my payment recognized from my email name that I am a UConn fan. She's a Tarheel fan and wasn't too pleased that we womped her team. I'll have to watch my credit card for unusual purchases.
Expand ...
Congratulations on your new memberships in several UNC NIL collectives.
 
Kolumbo said:
We installed a Navien propane fueled tankless water heater because we already had propane tanks in the backyard and it is awesome. It is attached to the wall and takes up very little space. We got rid of a hot water heater, an old oil furnace which was on its last legs, and an oil tank. Here is a photo I found online which is pretty much how ours looks.

View attachment 93804
Expand ...
We switched to propane and were thinking of a tankless water heater also. What does that cost all-in for a mid level system if you don’t mind my asking?
 
As someone who has designed and sold HVAC systems in both CT and GA I can probably help a little here. Standard efficiency split heat pump systems will still heat down to about 32-36 degree outdoor temperature. At that temperature they need to work harder and they switch on a secondary heat source. Typically this would be an electric resistance coil, not all that different from an electric oven or a toaster.

It is important to know that most homes in CT need more BTUs to heat a home below freezing than cooling BTUs to cool a home when it’s 95 degrees outside. Let’s say you have a 2.5 ton AC system. That’s 30K Cooling BTUs. A 2.5 ton Heat Pump would be capable of producing both 30K cooling BTUs and 30K heating BTUs. That same house likely needs 60-70K heating BTUs in order to heat it to 70 degrees when it’s 25 outside. This means that even an inverter driven heat pump (think condensers like ductless mini splits) that will heat to 0 degree outdoor temp, would still not be able to heat your home.

There does exist heat pump condensers that will continue to heat to zero degree outdoor temperature. They just won’t provide you with enough heat. These are typically the most expensive and efficient heat pump systems available ($15-25K depending on brand). The best solution if Natural Gas isn’t available would be to look at switching to a propane heating system with a dual fuel set up. That’s a heat pump that switches to propane when it gets too cold.

Also keep in mind that just because your home is set up with ductwork to cool it, that doesn’t mean it’s set up to heat it.
 
.-.
StllH8L8ner said:
We switched to propane and were thinking of a tankless water heater also. What does that cost all-in for a mid level system if you don’t mind my asking?
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$5500-$6800 on average. Quite a bit less a few years ago. It’s a luxury item, not a big cost saver. Unless it lasts you 20 years.
 
Last edited:
uconnfan68 said:
Daughter in Mass just did a lot of work on their very old house. Were going to do geothermal, but were moved to air heat pumps and existing oil burner as backup. Their contractor said the new air heat pumps were good enough for Boston area weather and much cheaper than the geothermal.
Expand ...

Kolumbo said:
We installed a Navien propane fueled tankless water heater because we already had propane tanks in the backyard and it is awesome. It is attached to the wall and takes up very little space. We got rid of a hot water heater, an old oil furnace which was on its last legs, and an oil tank. Here is a photo I found online which is pretty much how ours looks.

View attachment 93804
Expand ...
That’s a high efficiency boiler that has a tankless coil. A tankless water heater that doesn’t heat your home looks pretty much the same. Just keep in mind that these aren’t built to last much longer than a regular water heater (10 years). It should be cheaper when you go to replace it though. 3-4 years ago a tankless water heater sold for $2800-$3800. I saw a quote not long ago for $8500. The last dozen I sold were between $5500-$6500. Keep in mind if it heats your home then it’s a boiler/water heater. Different animal.
 
Had one installed this year. They are very efficient. One thing you should understand is that the area where it will go needs proper airflow and that area will get cold air from pump.

We had to replace the original water heater which ran off the oil furnace. The area space is improved due to not needing a return pipe to the chimney. The utility room looks much better

I love the investment
 
oshkosh said:
A few years ago I bought my first house (built in the 90s) with all original mechanicals still chugging along. We have oil that fuels both the furnace (forced hot air) and hot water heater using oil burners, in addition to central A/C so the whole house is already ducted. I would like to upgrade all of this, preferably moving entirely away from oil. We are on borrowed time especially with the ol’ Superstor water heater ready to burst at the seams.

I see there are loads of incentives (energizeCT rebates + loans, federal tax credits) for heat pump units and hot water heaters, I just don’t know how well these perform in our climate and whether these are suitable replacements here.

I spoke to a couple HVAC tech’s who both mentioned that heat pumps need a backup heat source for cold days (<30 degrees F), yet I have seen units in my limited research that are rated for performance down to -15F.

I can recite the career stats of Ruslan Inyatkin on demand, but I simply don’t know jack about boilers, burners, furnaces, coils and that speak. Has anyone had a similar experience converting over these systems and can offer any helpful advice?
Expand ...
20 in Buffalo last night, house was really warm. Heat was pumping from our heat pumps.

It's an old house though so it keeps heat really well.

I imagine the problems start at 10.
 
StllH8L8ner said:
We switched to propane and were thinking of a tankless water heater also. What does that cost all-in for a mid level system if you don’t mind my asking?
Expand ...
If you are going to switch to a tankless, make sure your water is properly conditioned, either with a water softener or anti scale filter....that's a few extra $$
 
NJHusky said:
If you are going to switch to a tankless, make sure your water is properly conditioned, either with a water softener or anti scale filter....that's a few extra $$
Expand ...
Still an issue with city water? Just curious.
 
.-.
upstater said:
20 in Buffalo last night, house was really warm. Heat was pumping from our heat pumps.

It's an old house though so it keeps heat really well.

I imagine the problems start at 10.
Expand ...
Your electric strip heater will work with your heat pumps before the condensers shut off. That also helps them produce the extra BTUs necessary to heat a home vs cool a home. It’s more expensive at those temperatures but still better than when the heat strip is working alone. Solar is great if you’re an all electric heat homeowner.
 
B1GEast said:
Had one installed this year. They are very efficient. One thing you should understand is that the area where it will go needs proper airflow and that area will get cold air from pump.

We had to replace the original water heater which ran off the oil furnace. The area space is improved due to not needing a return pipe to the chimney. The utility room looks much better

I love the investment
Expand ...
Heat Pump water heater? Now those are awesome.
 
One more consideration for Heat Pumps, while they are the standard heat source across the sunbelt, those states have much lower electricity costs in addition to the warmer winters. Their efficiency even within their heating range is somewhat offset by our very high cost of electricity in New England.
 
B1GEast said:
Had one installed this year. They are very efficient. One thing you should understand is that the area where it will go needs proper airflow and that area will get cold air from pump.

We had to replace the original water heater which ran off the oil furnace. The area space is improved due to not needing a return pipe to the chimney. The utility room looks much better

I love the investment
Expand ...
I have a similar situation. My existing oil furnace and water heater are in a small unfinished part of my basement, with pipe going into the chimney. There's insulation between studs but no sheetrock, and there's a simple outside vent through the siding so it gets chilly.
 
bfs3 said:
As someone who has designed and sold HVAC systems in both CT and GA I can probably help a little here. Standard efficiency split heat pump systems will still heat down to about 32-36 degree outdoor temperature. At that temperature they need to work harder and they switch on a secondary heat source. Typically this would be an electric resistance coil, not all that different from an electric oven or a toaster.

It is important to know that most homes in CT need more BTUs to heat a home below freezing than cooling BTUs to cool a home when it’s 95 degrees outside. Let’s say you have a 2.5 ton AC system. That’s 30K Cooling BTUs. A 2.5 ton Heat Pump would be capable of producing both 30K cooling BTUs and 30K heating BTUs. That same house likely needs 60-70K heating BTUs in order to heat it to 70 degrees when it’s 25 outside. This means that even an inverter driven heat pump (think condensers like ductless mini splits) that will heat to 0 degree outdoor temp, would still not be able to heat your home.

There does exist heat pump condensers that will continue to heat to zero degree outdoor temperature. They just won’t provide you with enough heat. These are typically the most expensive and efficient heat pump systems available ($15-25K depending on brand). The best solution if Natural Gas isn’t available would be to look at switching to a propane heating system with a dual fuel set up. That’s a heat pump that switches to propane when it gets too cold.

Also keep in mind that just because your home is set up with ductwork to cool it, that doesn’t mean it’s set up to heat it.
Expand ...
My ductwork is used to blow heat and A/C from the blower throughout the house. I am looking into the dual fuel set up more because I already have propane tanks on site exclusively for the whole house generator (which never really gets used). I'm wondering if that is a safer bet vs a standalone heat pump.
 
Kolumbo said:
We installed a Navien propane fueled tankless water heater because we already had propane tanks in the backyard and it is awesome. It is attached to the wall and takes up very little space. We got rid of a hot water heater, an old oil furnace which was on its last legs, and an oil tank. Here is a photo I found online which is pretty much how ours looks.

View attachment 93804
Expand ...
Same boat, we have propane tanks for generator and thinking this could be doable. I would gather it is easier to maintain
 
.-.
uconnfan68 said:
Still an issue with city water? Just curious.
Expand ...
Depends on water hardness, which is determined by your water supply, city or well. I would assume city water has fewer particulates, but they don't filter out for calcium, magnesium that I know of...Those cause scale..if scales builds on the pipes, the heat transfer is dramatically decreased over time. If you have a tank, it doesn't matter as fire is blasting until the water comes to temp...with a tankless, you only have a second or 2 as the water cycles through.
 
oshkosh said:
I have a similar situation. My existing oil furnace and water heater are in a small unfinished part of my basement, with pipe going into the chimney. There's insulation between studs but no sheetrock, and there's a simple outside vent through the siding so it gets chilly.
Expand ...

One of the byproducts of the heat pump is that it blows out cold air. Nice in the summer though
 
Will provide my experience since I was faced with a similar decision this year. I have an oil powered boiler for floorboard heat and water heater that is well on its last legs (30+ years old). Was trying to decide to replace with new boiler or switch to heat pump. After a few calls and quotes, I determined it was significantly cheaper to try the Heat Pump out this winter for just heat and not hot water and keep my oil burner as backup and to handle hot water. The upfront cost for the Heat Pump was ~$6,500 but received an instant rebated of $750 and was given $500 for my 4 year old outdoor condenser from my central AC, so $5,250 upfront. I also will qualify for $2,000 Federal Tax credit and (supposedly) $1,000 per ton through Energize CT for a 3 ton system. This would bring my final cost down to a whopping $250. Note: I submitted my rebate form through Energize CT 2 months ago and am still waiting to hear back.

I got my Electricity Bill for November and my usage was up 35.6% compared to last November increasing my bill by ~$71. My oil consumption was down 70% saving me ~$350 with a net energy cost savings of ~$280. Assuming the Energize CT rebate comes through, the unit has already paid for itself.

As far as performance in colder temps - have yet to really see how far it can go. It's done perfectly fine keeping my home at 68 degrees so far and that was with the same warning from the installer that it becomes less efficient and can struggle to heat the home below 30 degrees. I know it doesn't "recover" temperature as well as the floorboard heaters so I just keep it pretty much set at 68 despite the smart thermostat being able to fluctuate the temp by time of day pretty easily (I do let it get "down" to 66 while we sleep).

If this keeps up through December and into January (and I get my Energize CT rebate), I'm inclined to dump the oilburner and switch to an electric water heater in the coming year. Installer also noted about something that can be added to my existing heat pump to make it work well even in extreme cold (below 0) temps which I would also do if I get rid of the oil backup altogether.
 
Matrim55 said:
Check out this guy's YouTube channel. He lives in Massachusetts & just built a net zero home, and does great, in-depth looks at stuff like heat pumps, solar panels, etc. He's very pro-heat pump:

Expand ...


Maine is one of the biggest growth markets in the country for heat pumps. They must be able to function on some level in cold weather.
 
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