With the cold weather I was hoping to hear of some experiences people have had with their heat pumps.

What kind of backup heat do you have? Are you using it? Is there some temperature where you just stop using the heat pump, or are you even consciously thinking about it?

Thanks!

  • @AnotherDirtyAnglo
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    184 months ago

    For anyone wondering, you should absolutely get a heat pump – the savings are still substantial, even if you need to use an alternate heat source for the coldest days of the year. My annual electric costs are down over 50% since switching about 4 years ago. For the couple days a year when the heat pump doesn’t do the job, it supplements with electric heat.

    • @GrindingGears
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      4 months ago

      Here’s the thing though, 50% reduction in my electrical use is like $30 a month. It’s going to take quite a few years of 50% to make a $10k cost difference justifiable.

      Don’t get me wrong, I’m all for heat pumps in principle. I personally have a heat pump heating my pool. I put in central air conditioning a couple years ago, and took a serious look at it for the house, but it was going to be more than double the cost. My electrical bill isn’t the problem either, it’s all the damn fees and riders that drive it into the stratosphere, not usage.

      So that + the fact I live in Southern Alberta and it might not be very useful 4 or 5 months of the year, I just can’t make it make sense. The government is going to need to give out more grant $$ before I’ll consider it.

      • @AnotherDirtyAnglo
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        4 months ago

        My total bill dropped, because the number of kWh dropped, and most of the distribution fees are linked to consumption.

        For me, I was replacing my furnace anyway (builder grade crap) and I wanted the most efficient unit I could get – because summers are only getting hotter. I managed to upgrade from 2-ton AC to 2.5-ton heatpump, but the total cost (tax included) was approaching $12k). I may not get back every penny I spent in electricity savings, but the house is more comfortable, and it’s nice to know I have extra heating/cooling capacity as the weather gets more extreme.

        • @GrindingGears
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          24 months ago

          There’s definitely a pretty good argument to be made there too, I won’t deny that. You are right, the summers are getting longer drier and gnarlier, and the freezes are getting worse too. We often have to deal with a lot of smoke later in the summer too. I for sure took a real close look at it a couple years ago, just as those grants and stuff came online, as we were doing our AC at the time.

          The reality for my household, is that in current state and location we just don’t use enough hydro to justify the cost versus the benefits. Now does that change in the future, as my kids get older and the climate continues to change? Hey, maybe, never say never. Also I think if you are a household in SW Ontario, or anywhere near the lakes, absolutely I’d be taking a very very close and serious look at one. I just couldn’t get the math to math at the moment, in my location.

      • jadero
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        44 months ago

        You might be surprised. I pulled 10 years of data for Lucky Lake, SK from environment Canada and the average number of days below -15C is 62. Our personal heating season is about 220 days (first use to last use, no matter how minimal). That works out to about 72% coverage for one of the less capable heat pumps.

        Others have suggested a minimum of -20 for long-term reliability. I didn’t do that analysis, but I did for below -25 and the average number of days is more like 21. IIRC, below -30 was no more than a dozen, on average.

        Obviously, every household’s calculations are different. Yours sound like it’s not worthwhile from a strictly personal finance perspective.

        • @AnotherDirtyAnglo
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          44 months ago

          Precisely. You might pay more for heat on a couple days a year, but overall the advantage is huge.

        • @GrindingGears
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          4 months ago

          I definitely should look at the details closer for our area. My big concern is with the big negatives, is mainly are these units going to last? Even though the ratings go to -15 or -20, the facts are that efficiency falls off a cliff even before you start getting into negative temps. At -15 you are using more energy than you would otherwise be with conventional heating sources. Now does that offset with more efficient days, I mean it probably does, it has to. But that doesn’t factor wear and tear. I mean that might be concern that’s all for naught too, but I just want to sit back a bit and see, personally.

    • @[email protected]
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      64 months ago

      Not in Alberta, but God I miss my heatpump in my last apartment. It saved me so much money vs. resistive heating and a portable AC. It even had a backup resistive heater, but it worked pretty well even into the deep negatives.

      • @GrindingGears
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        4 months ago

        We had a heat pump in our condo. Thing was nightmare fuel, and always broken. I don’t hold it against heat pumps though. It was a proprietary sized unit, and when it broke we had to wait for parts from like Baltimore or something like that. Only one company made parts, and then they shut down.

        • @[email protected]
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          24 months ago

          Ugh, I’m sorry about that. I hate proprietary stuff / stuff that isn’t repairable. It’s a nightmare to fix.

          Hopefully, you have a better one someday!

          • @GrindingGears
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            24 months ago

            Oh that was in our condo, a few years back. We live in a house now. It was def a brain dead design, and unnecessary. Usual developer bullshit. That building signed a new long term maintenance agreement with another company while we were there, and they sourced a commercially available unit that would work. So everyone got to spend $4k, but no more issues. Not my problem now anyways, thankfully.

    • @NotAnArdvarkOP
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      34 months ago

      One thing that makes me wary is that this electric supplementary heating is needed at exactly the same time the grid is under the most stress. Plus, as we all get heat pumps, we’re all going to need that extra electricity at the same time.

      If you already have a gas furnace, the case could be made to keep that as your backup. But that doesn’t seem ideal. It’s something to maintain, made worse by the fact it will be so infrequently used. Plus, you can never hope to get rid of your gas line/company.

      It makes me think ground source heating is the obvious answer, but, the cost…

      • @AnotherDirtyAnglo
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        24 months ago

        You should be talking to your electricity company about reliability and future-proofing if that’s something that worries you about heat pumps.

        As much as it sucks, if you’re an area where reliability is a problem, getting a propane-powered generator is the way to go… Even better if you can get the advantage of using the waste heat from the genny into your home (a.k.a. ‘co-gen’).

        • @NotAnArdvarkOP
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          24 months ago

          My concern is the entire grid - in Alberta at least.

          Whenever it’s really cold or really hot out our grid pretty much maxes out and if that happens to coincide with a calm day, I think we’re in trouble.

          It’s cold out - lets all watch the price of electricity hit $999/MWh this evening and think about whether we’d be comfortable if a couple thousand Albertans had to suddenly turn on their resistive heating: http://ets.aeso.ca/

        • @GrindingGears
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          14 months ago

          That would mean needing to talk to the Alberta government, and you might as well talk to spilled paint, for all the good it’ll do.

  • @KingOfTheCouch
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    44 months ago

    This particular winter has been perfect for a heatpump+gas combo. Mostly been between 0 to -15, so it did its thing and ran relatively cheap. Technically we don’t have to think about it, because the way the thermostat we have works is if house can’t hit desired temperature after set amount of time (at or below 2 degrees from target for 45 minutes in our case - this can be adjusted a bit if desired) it kicks over automatically to the gas. Since we saw this almost -40 crap coming we just put it to gas only a couple days ago just to not think about it. I think there are “smarter” thermostats out there, but this has worked fine for us.

  • @lazylion_ca
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    -84 months ago

    From what I understand, you only use a heat pump until the outside temp reaches 0c, maybe -5c. Below that you go back to using the furnace.

    One of the big draws of a heat pump is pumping heat “out” of the house in summer instead of running an air conditioner. If you get a chilly spring night, the heat pump should maintain the house temp without running the furnace. Supposedly it does both of these more economically than running an AC and furnace, but it is not a replacement for a furnace.

    • @zaphod
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      4 months ago

      This is outdated. Modern heat pumps are good down to -15 or even -20 and new models are getting more and more efficient every day.

      That’s not to say folks in Alberta shouldn’t maintain a backup furnace of some kind, but today a heat pump should be good for heating and cooling 300+ days a year.

      Also:

      Supposedly it does both of these more economically than running an AC and furnace

      There’s nothing “supposed” about it. It’s basic physics: moving heat around is far more energy efficient than heating something up directly.

    • jadero
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      94 months ago

      Senville claims that some models are good to -30C. Even their “cheap” stuff seems to be good to -15 or -20

      • @AnotherDirtyAnglo
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        64 months ago

        Mine works down to -25 or -30C, then the electric heat coil in the furnace kicks in.

        • @NotAnArdvarkOP
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          24 months ago

          Wow - so you’re saying not until around -25 to -30 does supplementary heat kick in? Is there cool air being blown out your vents 24/7 around that temperature?

          • @AnotherDirtyAnglo
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            44 months ago

            Not at all… It’s consistently warm, the system stops running the heat pump when it’s not getting enough heat from the outside unit, and turns on the electric heater.

          • @ILikeBoobies
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            14 months ago

            That would be the heat pump heats well enough until those temperatures

        • @GrindingGears
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          4 months ago

          It works maybe, but it’s definitely not efficient at those temperatures. Plus your unit won’t last very long if you are driving it that hard. Lots of bold claims by these manufacturers, but let’s check in, in a couple of years to see how that’s going for the units.

          My pool pump, the minute it hits about 6 degrees out, it starts icing and efficiency is out the window. I have to shut it down at night, because it often gets too cold in the evenings for it on the prairies, even in summer. When it hits about 10 degrees outside though, you fire that bastard on and it’s warm in like 2 hours tops.

          • @AnotherDirtyAnglo
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            44 months ago

            Less efficient, yes, but the system knows the temperature outside, and switches to electric heat automatically. Also, -40C is usually for short periods of time, and becoming more rare – the advantages far outweigh the issues.

            As for your pool – it’s likely not built to the same standard as your home heat pump – and the icing sounds like a problem that might require some maintenance.

            • @GrindingGears
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              24 months ago

              The pool heat pump is fine, it’s a smaller unit so it’s not like a house one that can go to low temperatures. We also live at 3,400 feet of altitude, the operating curve for heat pumps is different at any altitude vs what they are at sea level (which is what I believe the manufacturer quotes it at). When we bought it, that was one thing that was mentioned in the literature, that they aren’t as efficient at higher altitudes and thus can’t operate at as low of temperatures.

        • jadero
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          14 months ago

          Good to hear. As soon as we can afford it, we’ll be installing one.

          The subsidy doesn’t cover us because we’re in a mobile home. If we get someone to pull the axles off, we’d qualify, but that’s yet more money.

            • @GrindingGears
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              4 months ago

              The federal government has one that is part of their Greener Homes Program. I believe there’s also an Oil to Heat pump program.

              We took a look at it for our place in Calgary when we installed our air conditioning, but the incentive was for around 5k. The provincial government doesn’t offer anything here, so the A/C unit we looked at was about $4,500 done and dusted for a 2.5 ton name brand vs. about $12,500 for a heat pump. I’ll tell you, if the subsidy would have covered another $1.5 to 2k, I would have taken a much much more serious look at it, just for even the AC aspect alone. Or if the province offered anything, but it’s all oil and gas here, and the provincial government is much too busy lining their own pockets and the pockets of their supporters with single sourced procurements, but anyways

              My FIL, who lives in Southern Ontario, put one in and loves it. He said it was a slam dunk decision with the subsidies, as there are both provincial and federal ones there I believe.

                • @GrindingGears
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                  4 months ago

                  1600sq ft. We need a cold climate pump, which is more expensive.

          • @AnotherDirtyAnglo
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            24 months ago

            In the short term, it might make more sense to spend some money on insulation… My uncle lived in one in Northern Ontario, and even though it was skirted and sheltered by the forest around him, the fuel costs each winter were punishing.

            • jadero
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              24 months ago

              it might make more sense to spend some money on insulation

              Already done! :)

      • @HewlettHackard
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        44 months ago

        Keep in mind that while the heat pump works at low temperatures, it produces less heat. Senville’s 36000BTU unit produces just 27000 BTU at 17f per AHRI. The drop in output is an important consideration when evaluating system sizing and backup/auxiliary heating.

        • jadero
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          14 months ago

          Thanks for the additional information! I’m still trying to get past all brochures and promotions to real data.

    • @[email protected]
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      64 months ago

      Daikin, Mitsubishi say -13F.

      You can switch on an aux heat source after that. Resistive, gas, wood. Most air handlers have optional resistive heat.

      An air conditioner is a heat pump. Very little difference.

      • @HewlettHackard
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        14 months ago

        It’s not quite that simple; the output drops as the temperature gets really cold, so auxiliary heat likely kicks in before the heat pump actually shuts off. They’re still great, efficient technology, but when considering auxiliary heating needs and system sizing, the reduced output at low temperatures needs to be considered.