Our A/C is getting pretty long in the tooth. It froze up last week and the tech who fixed it had to put 2 or 3lbs of the 'old' style refrigerant in as it was pretty low. The most likely cause being a pinhole leak somewhere in the system which would be a real bear to find, even if it was somewhere accessible. He suggested we start pricing a replacement.

I'm okay with replacing it for a more efficient system but I'm wondering the best way to go. Last time I had my furnace serviced, the tech pointed out some corrosion starting inside the heat exchanger.

Disregarding installation costs, are heat pumps that much more efficient than a new furnace/AC system? How about pricing? are they comparable size for size? The replacement has to heat/cool a 3000 sq foot 2 storey house in Northern Minnesota, so hot (short) summers and (long) very cold winters.

I do not think a HP is the way to go in the cold country. It is way to cold for the heat pump to do much good on the heating side of things with the type of winter demand your climate demands. So no on a HP.

What did your hvac guy say?

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What did your hvac guy say?

He recommended it, they install them quite often according to him.

Do you have natural gas heat now ?

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Originally posted by selogic:
Do you have natural gas heat now ?

LP


.

If you get one you may be eligible for a tax credit.

Tax credit info click here

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Originally posted by old rugged cross:
I do not think a HP is the way to go in the cold country. It is way to cold for the heat pump to do much good on the heating side of things with the type of winter demand your climate demands. So no on a HP.

What did your hvac guy say?

I'm with ORC on this one. We can't even get decent heating in a relatively small space with a heat pump here in Maryland where we might have a sustained week or two with temps in the 20s during the winter. They run on "auxilliary" or "emergency" heat the entire season.

I can't imagine how useless a heat pump would be in Minnesota.

-Rob

I’m guessing your condenser and compressor for your AC are really small compared to what you would need for a heat pump in MN. The heat pump will work for part of the year (above 30 degrees), but you’re going to have to have another source of heat. I’m guessing by the time the numbers are run on a much larger AC/heat pump than you currently have plus a new furnace, you’ll find the price difference with just an AC and furnace won’t be offset by any energy savings.

Despite being the same sq/ft, the condenser on our house in MI is the size of a dorm fridge. The one on our house in FL is 5-6 times as large and a bit smaller than the AC/heat pump it replaced. I’m guessing one in MN is going to be even bigger than the one we had in FL.

In my opinion, heat pumps don't work well here in Nashville. When it gets "cold" here heat pumps won't work and the back up heating system, electricity, kicks in. This is very expensive. I would think your heat pump issues in Minnesota are an order of magnitude worse than ours. Talk to some of these people your HVAC says have gone to heat pumps and see what their heating bills are.

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Originally posted by Pyker:

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What did your hvac guy say?

He recommended it, they install them quite often according to him.

Thinking you may want to get a couple more quotes. Not sure I would use this guy.

Interesting, a little googlization on Heat Pump ranges say they work well down to -15 degrees, that the technology and ability of the current models to heat properly in colder climates has significantly improved.

Link

According to Dave Lis, director of technology and market solutions at Northeast Energy Efficiency Partnerships (NEEP), air-source heat pumps can work as a home’s main heating system in almost any climate.

In the meantime, the NEEP, Lis’ organization, maintains a database of heat pump models that will perform well in cold weather. Many models in the database can heat as effectively at a frigid 5° F as they can at a mild 47° F, and can also work pretty well at temps well below zero. In other words, these heat pumps are built for the big swings in temperatures that the Northeast and Midwest see every winter.

Link NEEP Cold Climate Heat Pumps

More at the article link on how Heat Pumps, properly configured can work in cold climates.

That could be. And advances do happen. But for me history is a good indication of things and there is basically no history on new ones preforming when history tells us they don't. Others can be the guinea pig.

Guys, your info on heat pumps is dated. Also OP stated he has LP, so I don't understand why electrical costs for emergency heat would matter because the system would use LP.

He decision is between LP only and heat pump plus LP. He will save money on heating costs.

I agree with Rob

I currently have a heatpump in MD and it sucks in the winter especially when temps get below freezing.

Heat pumps heat a house slowly. The air I get out of the vents is just a little warming than the air in the house. Forget about lowering the heat more than a degree or two when you are not there or at night and expect it to warm up quickly. In the past, I've had NG and heating oil both were much better.

If you have gas now I would go with that. If you lived in a warmer climate then a heat pump is fine but not with temps getting close to and below freezing.

Good to know heat pumps have improved, -15 is incredible. What’s the curve for electricity use look like on the way down to -15?

Is my guess that an AC/heat pump and furnace is going to cost more than just a regular AC and furnace in MN correct? He should still compare the difference to any energy savings before making a decision.

Since the heat pump will be sized for heat, will it then be oversized for AC in the summer and thus require a dehumidifier, or a two stage compressor?

You should look into a inverter style mini split system. I had a multizone Blueridge system installed in March and love it. I missed out on using it during the coldest months because of shipping delays but it still provided plenty of heat when it got in the teens. Somehow they figured out how to pull heat out of the air at as low as 22 degrees below zero. They're not cheap but it's nice to get heat in the winter and cold air in the summer, a whole new experience for me. There is the added benefit of a tax credit also.

On this forum heat pumps are not well thought of.

Part of the problem is that the climate nazis have portrayed gas as bad and electric as the only good option. This makes most folks around here fall in the anti electric camp. Another part of the problem is that for the longest time many of the utilities have been pushing gas to avoid taxing an already burdened electrical grid. Now throw in some strong marketing by the heating oil industry and some poorly installed units and heat pumps get ran down.

As a contractor I do not care what systems get installed, as long as the customer is happy with what they get. But saying that a heat pump does not work in a northern climate is not accurate. Not only will a properly selected and installed heat pump comfortable heat and cool a building in harsh winters, they can have a lower cost of operation than LP and even natural gas depending of circumstances. In any case if you need a new AC it would be best to find a local dealer that can help you get what is going to work best for you whatever that may be, but a heat pump is nothing to be afraid of.

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Originally posted by Skins2881:
Guys, your info on heat pumps is dated. Also OP stated he has LP, so I don't understand why electrical costs for emergency heat would matter because the system would use LP.

He decision is between LP only and heat pump plus LP. He will save money on heating costs.

quote:

Not only will a properly selected and installed heat pump comfortable heat and cool a building in harsh winters, they can have a lower cost of operation than LP and even natural gas depending of circumstances. In any case if you need a new AC it would be best to find a local dealer that can help you get what is going to work best for you whatever that may be, but a heat pump is nothing to be afraid of.

The HVAC estimator just left. He's pricing a 3 ton equiv. Bosch air source heat pump (good to -22) vs a standard 3 ton A/C unit, both to work alongside our existing 95% efficient 80K BTU LP furnace. In either case, he's recommending a change from a 16x20x1 filter housing to a 25x20x4 to improve airflow.

The raw numbers look like a saving of about $20 a week on LP in the winter and $5+ on electric in the summer for HP vs A/C.

I'll see what the written quote comes in at. I'm comfortable with the HVAC company, they've always treated me well in the past.

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he's recommending a change from a 16x20x1 filter housing to a 25x20x4 to improve airflow.

Just did this, a good idea, plus the separate housing makes changing filters a breeze..

We put in the UV light in at the same time, theres a lot of + and - comments but the AC people said whenever there is a UV light in the system its significantly cleaner than when not..

With all the things in the air especially here, for $200 installed it was worth it...

I lived in the Great White North. Heat pump will provide little heat at substantial cost. Visitors constantly complained it was too cold during the winter months.