Home Heating; oil furnace, heat pump, hybrid gas furnace/ heat pump

The Coffee Shop
1

I want to upgrade my Long Island house. Right now we have a 60 year old oil furnace. I was thinking about a heat pump but I keep seeing articles where the owner isn’t happy with the system, and L I isn’t really very cold anymore. I can’t think of one time I had to bundle up to run in the morning and I haven’t worn a coat in years. My wife gave my dress coat to charity saying ‘‘you never wore it’’.

The oil furnace has never been a problem, it’s jus out of date. I heat pump seems like the way of the future but not the present. A hybrid gas/heatpump system;

https://www.trane.com/residential/en/resources/blog/hybrid-heat-systems-how-they-work/

Seems like a perfect compromise, kind of like the Toyota Rav Prime plug-in that we just got. Does anyone have any experience switching to a heat pump or to a hybrid system.

I’m spending my mandatory dispersals so what ever I do is affordable. I just want to get the best system for now as well as the future.

2

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

3

The obvious first question is do you have gas in the street…

Second: air-air heat pump or air-water?

I’m quite happy with an air source heat pump, and I probably get hotter and colder in central Mass (not as hot as the CT Valley though)
Ground source/water source heat pump are probably too $$$ to make the payback any use. $50,000 in drilling isn’t great in the short term.

4

Not sure, but I’m following this thread as it’s relevant to me.

I live in Boston burbs, have an aged oil furnace that is going to die soon, and I’m trying to figure out what to do.

Where I live (and based on some neighbors’ experiences), relying solely on heat pump is a bit risky. Having a hybrid/oil source backup is useful in our part of the world.

Also, the economics around here depend in part on whether you have air ducts or forced hot water for current heating. We have forced hot water. It can sometimes be harder/more expensive to convert to heat pumps if you don’t have existing duct work to use.

5

The obvious first question is do you have gas in the street…

Second: air-air heat pump or air-water?

I’m quite happy with an air source heat pump, and I probably get hotter and colder in central Mass (not as hot as the CT Valley though)
Ground source/water source heat pump are probably too $$$ to make the payback any use. $50,000 in drilling isn’t great in the short term.

We have gas in the house. We have a gas range, gas hot water and a gas cast iron stove in the living room. We also have forced hot air heat right now and we don’t have central air. We have a split unit in the living room that takes care of most of the house, and window units in the walls that we use only when it’s really hot.

It seems like the hybrid system would be perfect. I should so something about my 60 year old furnace, and I’d like to stop contributing to the USA Oil Cartel. It looks perfect until I see the cost of such a system, then I’ll crap my pants. But I am spending my manditory dispersal money so it doesn’t matter that much.

Does anyone know anything about these hybrid systems?

6

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

Heat pumps can definitely work well in “extreme cold”. Mine has worked well in the 20s. Efficiency is not as high, but COP is still like 3.9. You just need to make sure they are sized correctly.

7

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

Heat pumps can definitely work well in “extreme cold”. Mine has worked well in the 20s. Efficiency is not as high, but COP is still like 3.9. You just need to make sure they are sized correctly.

Did you have a conventional system before? Do you have any info on cost to run verses a conventional system?

On Long Island, PSEG is pushing heat pumps. It seems like it could be a great thing, but I don’t want to spend a bunch of money only to regret it next January.

8

I live in Massachusetts and have gas heat. We out in heat pumps 2 years ago mainly for the a/c. First winter we used them solely for heat and they kept up fine but struggled a bit in a couple short really cold periods (10-20F).

What we realized is that the gas heat uses more energy but is cheaper to use right now for heat since electric rates skyrocketed this past year. So we used gas heat this winter. In the buffer seasons we use the splits for heat since they don’t have to work hard so are more efficient and cheaper.

I think they will keep up most of the time on LI and might be cheaper in the winter than oil. I would want a backup heat source for 2 reasons…

This winter our furnace broke a bit so it was great to have backup heat for a bit.

Last year my sister in laws pipes froze so they weren’t able to use their furnace for a few weeks but thankfully they had splits to use for heat for a month. It’s really nice to h e a backup.

9

We have a heat pump w gas furnace backup (called dual-fuel system around here.) We are happy with it and running costs have been very reasonable. I run the heat pump most of the time and the furnace kicks in on only the coldest of days. We live in coastal mid-atlantic region, BTW. I think I pay 6 cents per KWHr for electricity, and our bills are never more than $60 per month. House is ~2700 sqft, well insulated

I’d say if you go this route, its worth it to get a high efficiency, multi-stage, multi-fan speed unit.

10

I live in Massachusetts and have gas heat. We out in heat pumps 2 years ago mainly for the a/c. First winter we used them solely for heat and they kept up fine but struggled a bit in a couple short really cold periods (10-20F).

What we realized is that the gas heat uses more energy but is cheaper to use right now for heat since electric rates skyrocketed this past year. So we used gas heat this winter. In the buffer seasons we use the splits for heat since they don’t have to work hard so are more efficient and cheaper.

I think they will keep up most of the time on LI and might be cheaper in the winter than oil. I would want a backup heat source for 2 reasons…

This winter our furnace broke a bit so it was great to have backup heat for a bit.

Last year my sister in laws pipes froze so they weren’t able to use their furnace for a few weeks but thankfully they had splits to use for heat for a month. It’s really nice to h e a backup.

MA resident here too, and considering mini-splits to supplement our current oil heat paradigm (and give us some cooler air in summer).

Do the splits and the furnace ‘talk’ automatically, or do you have to manually turn one on, and turn the other off?

11

We recently installed a Haier arctic heat pump living close to the Canadian border. But it is also for AC in the warming summer months. We have an oil burning furnace but with the high costs of oil this winter, we heated primarily with both our wood stoves (got an amazing fireplace insert along with our soapstone woodstove). And the heat pump was great as supplemental heat especially first thing in the mornings before we got the woodstoves going. We are off the electrical grid but have a beefy solar system, so the heat pump was great on those cold very sunny winter days. We only ran the oil furnace a few times this winter when the temps hit below -10F.

We like our heat pump/AC so far.

12

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

We have a heat pump and an older, not so well insulated house in western Canada. We also have a gas fireplace. Since getting the heat pump, we barely use the gas fireplace. It seems to keep up just fine, our winters are usually 0-5*C (32-45F) with dips that go down a further 10 degrees or so. Our heat pump is also on the weaker end for the size of our house (probably should have gone 2.5ton, went 2ton).

No issues thus far.

13

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

Heat pumps can definitely work well in “extreme cold”. Mine has worked well in the 20s. Efficiency is not as high, but COP is still like 3.9. You just need to make sure they are sized correctly.

Did you have a conventional system before? Do you have any info on cost to run verses a conventional system?

On Long Island, PSEG is pushing heat pumps. It seems like it could be a great thing, but I don’t want to spend a bunch of money only to regret it next January.

This house has only had a heat pump. Even my hot water heater is a heat pump. I live somewhere they make tons of sense. Electricity is cheap, gas is expensive, and it doesn’t get below 10 degrees much.

Cost to run compared to conventional system really depends on where you live and the cost of electricity versus the rate for natural gas if you are using anything but natural gas, like oil, I would bet heat pumps will be cheaper). If you want to work out the math yourself, you can convert the therm rate you pay for gas to the kw-hr you pay for electricity and then coefficient of performance of the heat pump (which will depend on the model and also the outside temp), to get a good comparison for the costs.

Basically if you see that your therm rate converted to kw-hr is 1/5th the kw-hr rate you pay for electricity and you heat pump COP is 5, each one costs the same to run. If your COP is 4, gas is cheaper.

But heat pump COPs and maximum output change with temp. Below 20 degrees the COP may be below 4, but above 50 over 5. So maybe January you spend more than if using natural gas, but every other month the heat pump is cheaper. Also you want to size the heat pump for what sort of heat output you need when it is cold. And of course some stop working at a certain temp.

Of course you will have the system of a long time, so the rates you pay today are only part of what you should look at. I expect that natural gas rates may increase more in 10 years than electricity rates. But maybe they won’t.

There are sites online that can look at your local weather, both average temps and outlier temps to help you size and pick out heat pumps.

14

I live in Massachusetts and have gas heat. We out in heat pumps 2 years ago mainly for the a/c. First winter we used them solely for heat and they kept up fine but struggled a bit in a couple short really cold periods (10-20F).

What we realized is that the gas heat uses more energy but is cheaper to use right now for heat since electric rates skyrocketed this past year. So we used gas heat this winter. In the buffer seasons we use the splits for heat since they don’t have to work hard so are more efficient and cheaper.

I think they will keep up most of the time on LI and might be cheaper in the winter than oil. I would want a backup heat source for 2 reasons…

This winter our furnace broke a bit so it was great to have backup heat for a bit.

Last year my sister in laws pipes froze so they weren’t able to use their furnace for a few weeks but thankfully they had splits to use for heat for a month. It’s really nice to h e a backup.

MA resident here too, and considering mini-splits to supplement our current oil heat paradigm (and give us some cooler air in summer).

Do the splits and the furnace ‘talk’ automatically, or do you have to manually turn one on, and turn the other off?

The mini splits and gas furnace do not talk to each other. We power one system on and the other off and vise versa. They may have some that do talk but I dont think they do.

We had to get oversized units for our house to meet rebate requirements (weird that bigger met requirements and smaller didn’t) but they are engineered to only work as hard as you need, so bigger is not really a whole lot less efficient. I would not undersized them, they just work harder/less efficiently and struggle to keep up.

We got nice Mitsubishi and they are wall units. I really wish we had ducts so they wouldn’t be mounted on the wall but it is what it is.

We got about 5k in rebates and a 7 year 0% loan which makes the whole thing pretty reasonable

15

For what it’s worth. We were earlier adopters of mini-splits in our old house, Fujitsu and they were pieces of shit. One broke right after warranty was up, main circuit board. Annual maintenance to keep the things clean (3 of them) wasn’t cheap. Also, heat was nice where it came in (heat rises remember) but other end of room wasn’t. New (old house) is baseboard and lot of it, with 4 year old high efficiency gas. Cheap to run, but we have small house.

Do full cost analysis including warranty/services for whatever you are buying and from a dealer that you respect.

16

I live in Massachusetts and have gas heat. We out in heat pumps 2 years ago mainly for the a/c. First winter we used them solely for heat and they kept up fine but struggled a bit in a couple short really cold periods (10-20F).

What we realized is that the gas heat uses more energy but is cheaper to use right now for heat since electric rates skyrocketed this past year. So we used gas heat this winter. In the buffer seasons we use the splits for heat since they don’t have to work hard so are more efficient and cheaper.

I think they will keep up most of the time on LI and might be cheaper in the winter than oil. I would want a backup heat source for 2 reasons…

This winter our furnace broke a bit so it was great to have backup heat for a bit.

Last year my sister in laws pipes froze so they weren’t able to use their furnace for a few weeks but thankfully they had splits to use for heat for a month. It’s really nice to h e a backup.

MA resident here too, and considering mini-splits to supplement our current oil heat paradigm (and give us some cooler air in summer).

Do the splits and the furnace ‘talk’ automatically, or do you have to manually turn one on, and turn the other off?

Depends on the control system, but yes they can.

Commercial systems have been doing that for ages

17

I live in Massachusetts and have gas heat. We out in heat pumps 2 years ago mainly for the a/c. First winter we used them solely for heat and they kept up fine but struggled a bit in a couple short really cold periods (10-20F).

What we realized is that the gas heat uses more energy but is cheaper to use right now for heat since electric rates skyrocketed this past year. So we used gas heat this winter. In the buffer seasons we use the splits for heat since they don’t have to work hard so are more efficient and cheaper.

I think they will keep up most of the time on LI and might be cheaper in the winter than oil. I would want a backup heat source for 2 reasons…

This winter our furnace broke a bit so it was great to have backup heat for a bit.

Last year my sister in laws pipes froze so they weren’t able to use their furnace for a few weeks but thankfully they had splits to use for heat for a month. It’s really nice to h e a backup.

MA resident here too, and considering mini-splits to supplement our current oil heat paradigm (and give us some cooler air in summer).

Do the splits and the furnace ‘talk’ automatically, or do you have to manually turn one on, and turn the other off?

The mini splits and gas furnace do not talk to each other. We power one system on and the other off and vise versa. They may have some that do talk but I dont think they do.

We had to get oversized units for our house to meet rebate requirements (weird that bigger met requirements and smaller didn’t) but they are engineered to only work as hard as you need, so bigger is not really a whole lot less efficient. I would not undersized them, they just work harder/less efficiently and struggle to keep up.

We got nice Mitsubishi and they are wall units. I really wish we had ducts so they wouldn’t be mounted on the wall but it is what it is.

We got about 5k in rebates and a 7 year 0% loan which makes the whole thing pretty reasonable

Also in MA here (just south of Boston). We just installed a ducted heat pump system in our in-law addition and it’s been great so far. No issues heating the in-law apartment through the winter, although it’s new construction with spray foam insulation which helps.

We don’t currently have central air in our main house and recently converted from oil to gas heat (forced hot water), but we’re going to install a ducted heat pump system there too. One air handler for each floor with a common heat pump, and new ductwork in the basement ceiling for the first floor and attic for the second floor. The contractor says he can integrate our existing hot water heating with the heat pump via smart thermostats. I’m not totally clear on how they work together but I assume the heat pump will be the primary heat source unless it needs help from the boiler.

*edited to correct my terminology.

18

I’m not totally clear on how they work together but I assume the heat pumps will be the primary heat source unless they need help from the boiler.

That is probably the most straightforward way to go about it, but I would guess that it should also monitor outside air temp to know if it is better to run the boiler or the heat pump. You could probably pick an outdoor air temp on either efficiency of the heat pump, which decreases as it colder, or the actual heat output of the heat pump, which also decreases as it gets colder. Rather than just waiting for the heat pump to not be able to keep up with the heating requirements.

I am sure there are fancy systems that take advantage of you are using variable rate electric plans. It could heat up your home at night when it is cheap and then let is slowly cool down at night when electricity is expensive or switch to the boiler.

19

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

We have a heat pump and an older, not so well insulated house in western Canada. We also have a gas fireplace. Since getting the heat pump, we barely use the gas fireplace. It seems to keep up just fine, our winters are usually 0-5*C (32-45F) with dips that go down a further 10 degrees or so. Our heat pump is also on the weaker end for the size of our house (probably should have gone 2.5ton, went 2ton).

No issues thus far.

This will be for a 1960s inexpensively built ranch. It probably has 2’’ of insulation in the walls, and I rolled out 12 inch insolation in the attic over the minimal stuff up there. It has modern Anderson windows. It will probably need some ductwork upgraded. And I want to go with a fully integrated hybrid system so I can set the thermostat like normal. I’ll keep the cast iron gas stove in the living room.

Here’s the system that I’m thinking about again;

https://www.trane.com/...stems-how-they-work/

Do you know anything about it, or any other hybrid systems?

20

I live in South Carolina with a heat pump. I have a wood stove as back up that I keep running on cold winter days. No way I would live up north with a heat pump and not have a wood or hybrid gas furnace for the cold days. In my experience heat pumps just can keep up in extreme cold. The emergency heat strip will come on all the time. And by extreme cold I mean under 50 Deg. F.

We have a heat pump and an older, not so well insulated house in western Canada. We also have a gas fireplace. Since getting the heat pump, we barely use the gas fireplace. It seems to keep up just fine, our winters are usually 0-5*C (32-45F) with dips that go down a further 10 degrees or so. Our heat pump is also on the weaker end for the size of our house (probably should have gone 2.5ton, went 2ton).

No issues thus far.

This will be for a 1960s inexpensively built ranch. It probably has 2’’ of insulation in the walls, and I rolled out 12 inch insolation in the attic over the minimal stuff up there. It has modern Anderson windows. It will probably need some ductwork upgraded. And I want to go with a fully integrated hybrid system so I can set the thermostat like normal. I’ll keep the cast iron gas stove in the living room.

Here’s the system that I’m thinking about again;

https://www.trane.com/...stems-how-they-work/

Do you know anything about it, or any other hybrid systems?

Hybrid systems work better in extreme temps, which we don’t really get, but have been being phased out here for years. Our city, along with Vancouver, actually just went full crazy on banning gas heat in new builds moving forward, so that, combined with incredible government rebates for electric heat pumps have meant that no one is really looking to hybrid systems here anymore.