Heat Pumps: Myth or Reality?

[Sylvain]

My 18 year old central A/C can't do the job anymore and makes as much noise as a small plane. Obviously, it has to go.

Are heat pumps really worth the additional cost (around $2000) in the Ottawa/Gatineau area?

Would someone know of a reliable source of info on this matter? Relying on sales people is a bit tricky...

Thanks.

[57]

Air conditioners ARE heat pumps, cooling the inside of the house using the "heat pump" method.

The decision regarding heat pumps should mainly be made regarding your heating. It also depends on the type of heat pump (ground, air, etc) that you are considering.

In northern climes, the "heating" requirement is much larger than the "cooling" requirement, therefore, the A/C portion is typically oversized and not as efficient as a properly sized A/C unit (they may have found some workarounds in newer heat pumps to make them more efficient).

Another concern of a "too large" A/C is the fact tht it will cool, but not dehumidify, making the house feel cool and damp. The smallest A/C unit that does the job, by running almost continuously on the hottest day is what you want.

The "best" geographical location for a heat pump is usually where the heat/cooling needs are equal, and that's typically a bit further south, say around Virginia.

I'll let others with practical information on heat pumps speak now, since there are people with heat pumps on this forum

Part of the decision is the payback, compared to a conventional system. A high efficiency furnace (say 95-98%) and a high efficiency A/C costs less initially, but uses more energy, but these energy savings of the heat pump need to be recouped in order to eventually break even.

The cost of the energy carrier is also important - gas, electricity, oil?.

If the additional cost of the heat pump is "only" $2000, then you'd only need to recoup about $2-300/year to make the investment worthwhile - payback in say 10 years. Look at your current heating costs to see if you think you can save that much with the increased efficiency of the heat pump. Your A/C costs may not change appreciably, since they're lower per year and there is not as great an efficiency improvement over your current A/C unit (although there may be some)

[Sylvain]

Thanks for the quick reply "57".

Since all energies have more or less the same cost (expensive), I don't think the type will change much in the equation. But your statement about the payback and saving is obviously key in the decision process.

Let me simplify the question: Do you save much with a heat pump or not?

The assessment tool on the hydro web site says I'd save about $20 per year. Obviously not worth looking into this. I know many people were disappointed with their actual savings especially as compared to sales staff promises (!). What's reality like?

[Monobloc]

What are you currently using to heat your home? If it is gas, how efficient is it?

[Sylvain]

Originally Posted by Monobloc

What are you currently using to heat your home? If it is gas, how efficient is it?

I'm using electricity which, I believe is nearly 100% effective. Why would that matter though? Isn't the idea to heat your home with the heat pump for less money than with whatever else you were using before?

[57]

Yes, electricity is 100% efficient, however, gas furnaces (I've had one since 1990 at 98% efficiency) can have 95-98% efficiency and typically cost less (operating cost) than electricity due to the cost per BTU/Watt.

If you're not replacing a significant portion of your "furnace" (electrical heat) duty, there is no incentive to use a heat pump because that's where the savings are - in heating, as I stated previously.

I don't know what efficiency the latest heat pumps have, but in terms of the BTUs generated, they could have an "equivalent efficiency" of 200-300% (sound illogical, but it's easier to "move" heat than "generate" it.).

A heat pump ( for heating) is simply the equivalent of an A/C unit "turned around", with the heat being "pumped" inside, instead of outside.

[otown47]

Check out this site...theres lots of technical info.

http://oee.nrcan.gc.ca/publications/...sheatpumps.cfm

Your answer depends on a lot of factors that only you can answer.....like what fuel you use now, the age of your existing furnace, how cold it is where you live, how many weeks you use AC in the summer. Did you know that heat pumps only work efficiently within a certain outside temperature range. Let us know what you decide....

[Sylvain]

Thanks for the reference. In there, I found this statement interesting: "You may be able to reduce your heating costs by up to 50 percent if you convert from an electric furnace to an all-electric air-source heat pump." If it is true, I would save about $600 per year and the payback period would be pretty short.

I am just looking for people who can confirm that through experience...

Originally Posted by otown47

Check out this site...theres lots of technical info.

http://oee.nrcan.gc.ca/publications/...sheatpumps.cfm

Your answer depends on a lot of factors that only you can answer.....like what fuel you use now, the age of your existing furnace, how cold it is where you live, how many weeks you use AC in the summer. Did you know that heat pumps only work efficiently within a certain outside temperature range. Let us know what you decide....

[Sylvain]

Originally Posted by 57

... If you're not replacing a significant portion of your "furnace" (electrical heat) duty, there is no incentive to use a heat pump because that's where the savings are - in heating, as I stated previously. ...

Yes 57, I agree. Are there people out there who have found their heat pump to replace their furnace duty for periods long enough to save money?

[57]

Originally Posted by Sylvain

...reduce your heating costs by up to 50 percent

This is probably if there is little/no supplimentary heat required.

I would think that you're more likely to be in the 25% range in Ottawa. Saving 50% of the usage attributable to the heat pump, which would be roughly 50% of your total usage, therefore 25% savings.

I hope someone with direct experience can help you out with their own figures.

[Monobloc]

I don't know why anybody in Canada would have central air conditioning but not a heat pump. It's expensive to put in the A/C for what will work out to a few weeks of use per year. Yet you're heating for more than half a year and using traditional electric heat.

Unless Gatineau spends a lot of time below freezing in the winter, I'd go for the heat pump. If you're selling you'll get the money back in higher price and if you're staying you'll save the money in a few years.

[Sylvain]

Originally Posted by Monobloc

... Unless Gatineau spends a lot of time below freezing in the winter, I'd go for the heat pump. If you're selling you'll get the money back in higher price and if you're staying you'll save the money in a few years.

As far as I can see on the Ottawa/Gatineau charts, we're below freezing for about 4 months/year. I guess the bottom line is figuring out if there is a "business case" to spend the extra $2000 for the heat pump (as compared to central A/C).

[Sylvain]

I have to say that my heatpump is useless below the freezing point and, as such, useless from November to March (5 months). Considering the period when we don't use much heating (May to Sep, another 5 months), that leaves only April and October where it will be able to provide adequate heating. Not only that, I have to manually shut it off in the winter (with the breaker) because the stupid thing will "try" to heat the house even when it is below freezing and will run (for nothing) until the furnace kicks in. Unless my heat pump is not working properly, I don't think it was worthwhile...

[JohnnyG]

I went through this excerise a couple of years ago when our old A/C with heat pump went south on us. After a decent amount of investigation, I concluded that heat pumps are just not worthwhile in this part of the country where it gets really cold in the late fall/winter/early spring, and replaced it with a straight A/C unit.

The way heat pumps operate is that if it can't meet the heating demands, it goes into the foolishly named "emergency heat" mode which just turns on your regular heating system. Therefore, the heat pump is only good for maintaining temps and heating in more moderate climates.

For example, if you were to set back your digital thermostat at night, the heat pump would not be able to heat the house when the temp is to come up in the morning. Therefore, it would switch to emergency heat mode and activate your regular furnance. Once the house is at the set point again, the heat pump *might* be able to maintain the temperature but it depends on how cold it is outside and how hard you want the thing to work.

So basically, it's just too darn cold in these parts to make a heat pump worthwhile. You will get a few months of the year were it will be all you need, but it probably won't save you enough money to make that worthwhile.

[TKG26]

well saidi
one of the few reasons we dont sell or serivice air to air heat pumps. in ontario the market is simply not there,