# Heat pump sucks



## FaithFirst (Nov 2, 2013)

I have a heat pump that I feel is struggling drastically to keep my house warm. I guess it is supposed to run almost constantly to be efficient and I know that in colder temps it has to work even harder but I am not comfortable with that. I am going to look into installing a natural gas furnace next summer. 

I have a 1580 sq ft, 2 story house that we some day hope to add on to. 

Questions I have: How many BTU's do I need for a target minimum? Is it possible to set up the unit with both a programmable and a analog thermostat so if we lose power in an ice storm I still have heat? And finally, down-flow or up-flow?
Thanks


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## Snowfan (Nov 6, 2011)

Speaking as an HVACR tech, I would advise you to seek out a good, qualified HVAC professional. They will come to your house, look at the property, the house, construction and do a heat/cool load analysis. They will sit down with you and, after talking with you about what you want and expect, make a few suggestions. Replacing an entire system will not be a cheap initial investment, but a good, quality system, properly installed and maintained, will save you money in the long run and let you sleep better at night. Good luck.


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## FaithFirst (Nov 2, 2013)

Thank you snowfan. I had planned on bringing someone in. The AC unit outside still works well and all my ductwork is solid. I'm not afraid to pay more for a reliable, new furnace. Hopefully having the rest of the system in place will ease my costs.


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## Guest (Dec 15, 2013)

Natural gas furnaces have blower motors & other components that need electricity to operate . You could use a generator to power the furnace during a power outage & some people install smaller stand alone gas heaters for backup heat . I have a generator & a couple vent free gas heaters I can use if my furnace fails for any reason .


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## Guest (Dec 15, 2013)

As far as down flow or up flow it depends on whether your furnace is below or above your duct work . If your furnace is in a basement your duct would be above the furnace so an up flow . If your furnace is on the first floor & the duct is in the basement or under the house then a down flow .


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## RonM (Jan 6, 2008)

I always was told that when the temp gets around 20 they are not at all efficient, not designed for Northern climates.........


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## Guest (Dec 15, 2013)

Another thing to consider is using a gas furnace in conjunction with the heat pump . Most stand alone heat pumps are efficient until it gets too cold then they have an electric element that comes on & efficiency goes to crap . You can install them so that instead of the electric element coming on , the gas furnace would come on instead .


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## FaithFirst (Nov 2, 2013)

I like that idea WV Hillbilly. Not sure how much space it would require.


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## Guest (Dec 15, 2013)

High efficiency gas furnaces now vent through a fairly small pvc pipe so a chimney or large flue usually isn't needed & venting is fairly simple . You would need an area for the furnace to sit & be able to tie it into the existing duct & return air .


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## TnAndy (Sep 15, 2005)

RonM said:


> I always was told that when the temp gets around 20 they are not at all efficient, not designed for Northern climates.........



True, depending on the unit.

I installed a Mitsubishi mini split last year, and the specs on it say it works down to -14. 

We don't actually use the heat pump side of it, just the AC, as we heat with wood.....but a heat pump was only a few bucks more for the equipment, so I went ahead with it. Never know when you might step in a hole and be hard to bring in firewood that year.

While on the subject, you might consider a mini split system.....easy to zone the heat/cool rather than do the entire house. Very popular many places in the world where electric is way more expensive.

Thing I like was I could install the thing myself, except I paid a heat/air guy $100 to come out and vac down the lines, check for leaks and turn the gas loose ( units come pre-charged ). Cut out a WHOLE bunch of labor and profit for a heat/air company.


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## fishhead (Jul 19, 2006)

A lot will depend on how well your home is insulated.


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## FaithFirst (Nov 2, 2013)

WV Hillbilly said:


> High efficiency gas furnaces now vent through a fairly small pvc pipe so a chimney or large flue usually isn't needed & venting is fairly simple . You would need an area for the furnace to sit & be able to tie it into the existing duct & return air .


Venting isn't a concern, the closet the current unit sits in is above ground and against an exterior wall. But because of that closet I don't have much room to put a supplemental unit in. Might end up replacing the whole heat pump and leaving the AC.


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## michael ark (Dec 11, 2013)

Your unit should not run all the time .Have a tech run a manual j on your house to get the size unit you need.Just going of sq feet is not the right way to size your unit. [ame="http://www.youtube.com/watch?v=P1CrDPm7Sss"]http://www.youtube.com/watch?v=P1CrDPm7Sss[/ame]Heat pumps aren't made to run when it's really cold. That's why they have heat strip for back up. Check your duct work and make sure all the seams have mastic on them. If you have flex get rid of that and get hard pipe. You can get a gas furnace put in place of your air handler to make your set up dual fuel and have the best of both worlds. Mini splits are great because they don't have duct work to heat up or leak. But most are a eye sore . Here is the nicest one I have seen.[ame="http://www.youtube.com/watch?v=FMKAarDXk9s"]http://www.youtube.com/watch?v=FMKAarDXk9s[/ame]


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## FaithFirst (Nov 2, 2013)

michael ark said:


> Your unit should not run all the time .Have a tech run a manual j on your house to get the size unit you need.Just going of sq feet is not the right way to size your unit. http://www.youtube.com/watch?v=P1CrDPm7SssHeat pumps aren't made to run when it's really cold. That's why they have heat strip for back up. Check your duct work and make sure all the seams have mastic on them. If you have flex get rid of that and get hard pipe. You can get a gas furnace put in place of your air handler to make your set up dual fuel and have the best of both worlds. Mini splits are great because they don't have duct work to heat up or leak. But most are a eye sore . Here is the nicest one I have seen.http://www.youtube.com/watch?v=FMKAarDXk9s


I'm reluctant to check the duct work because they are all in the ceilings. Also, some research we did said the strips only kicked on when the temp in the house dropped below 2 degrees difference from the set temp. It never reaches that.


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## Esprit (Dec 17, 2011)

We installed an 18000 BTU heat pump about a month ago. It uses the new style variable compressor. It's gotten as cold as 1.4F and it still pumps out the heat. You need to buy a good brand like Fujitsu if you live in a cold climate.


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## FaithFirst (Nov 2, 2013)

Esprit said:


> We installed an 18000 BTU heat pump about a month ago. It uses the new style variable compressor. It's gotten as cold as 1.4F and it still pumps out the heat. You need to buy a good brand like Fujitsu if you live in a cold climate.


Southern Missouri. I've never before experienced a winter this cold, this early and this prolonged here. Lived here for 9 years and I know this isn't normal. Hoping to eek out a few more years before I have to replace it.


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## Harry Chickpea (Dec 19, 2008)

You might want to have the person who comes out also do a basic diagnostic on the unit. Freon levels, in and out temps, defrost cycle, etc..

Another possibility is that the pump you have is undersized. We've been having similar outside temps and the pump isn't running much at all, even with a larger home.


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## FaithFirst (Nov 2, 2013)

Harry Chickpea said:


> You might want to have the person who comes out also do a basic diagnostic on the unit. Freon levels, in and out temps, defrost cycle, etc..
> 
> Another possibility is that the pump you have is undersized. We've been having similar outside temps and the pump isn't running much at all, even with a larger home.


Excellent Idea. A diagnostic check will be much cheaper than a replacement. We have the house set to 64. The air coming out of the vents almost feels chilly. Something can't be right.


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## TnAndy (Sep 15, 2005)

There is a HUGE amount of sorry duct work out there.

Our first house we built in 1975....small ranch style on a crawl space. Had a Lenox heat pump installed....our first experience with a HP. They did a "package" unit on the end of the house.....package being both the evaporator ( normally set inside in a split system) and the condensor/compressor unit ( normally the 'outside' unit ) are both together in the outside "package"(box). That means there is a dual set of duct work from the indoor return air vent ALL THE WAY BACK OUTSIDE to the package unit, where it is heated/cooled, then sent ALL THE WAY BACK INSIDE to distribute out to the floor vents.

Well, that has to be the easiest way to install it in that situation, and the worst way from a standpoint of heat/cooling loss over that long distance......because our 'heat' was the same way.....lousy. You could stick a thermometer in the floor vents, and read 80-82 degree air.....so, yeah, over time, it will heat the house. But blowing 80 degree air in the winter is cold to me. So after the first winter, we heated with wood the entire time we were in that house !

Lot of installers use undersized duct work.....outdoor unit in one of my rentals would freeze over solid in the the summer. Turns out the return air duct was way undersized. 

They also run long runs of flex duct, which is easy for them, BUT causes a lot of air volume lost out to the vents.


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## Harry Chickpea (Dec 19, 2008)

Flex ducts are also more prone to mice making holes and joints coming loose.


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## michael ark (Dec 11, 2013)

Heat pumps are not made to run like a gas furnace . But it will cost half as much to run on average. When you get a heat pump get the highest S.e.e.r you can afford. That stands for seasonal energy efficiency ratio. The higher the number the quicker the unit will pay for itself in real world money . Andy did they mastic all the seams on the supply and return. If not you are sucking outside air into the return at every seam and discharging the air you just paid to heat at the seams on the supply. I like a package units because it's safer over all. If anything goes wrong dead short ,fire etc. it's not happening in the occupied space. In my humble option flex duct is only good to sleeve over hard pipe.


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## Guest (Dec 16, 2013)

I would guess that what you have now in your closet is an air handler . It probably contains a blower motor , strip heat & a coil . There are furnaces made that have an empty space for the coil to mount . I would think you could remove the entire inside unit you have now & install one of these furnaces in it's place .
The coil could be installed in the furnace , the furnace blower motor would replace the blower motor you removed & the gas furnace would replace the strip heat & you would still have full use of the heat pump for both heat & ac .


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## NKyFarmGuy (Dec 10, 2013)

Sounds to me like something is wrong with your strip heat. The auxiliary may not be supplementing the outside air as it is intended. I'm certainly no expert though.


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## jhambley (Nov 21, 2004)

Most thermostats have an "Emergency" setting which ensures you are using the electric heat strip in the coldest weather. If the system is working correctly, you'll get the heat you need from the strip and the heat pump won't run. Just be aware that the heat strip will use a fair amount of electricity but it beats freezing to death in these temperatures.


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## Guest (Jan 9, 2014)

Here, people often install a heat pump with a gas pack. The gas pack will act as a gas furnace below the efficiency point of the heat pump. Not much more expensive, either.


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## davel745 (Feb 2, 2009)

heat pumps are only good for temps to 40 degrees F


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## michael ark (Dec 11, 2013)

We have been in the 15s here and my heat pump handled it fine. It ran a lot but it kept the house at 69. I ran out of firewood during the cold spell.:goodjob:
Get a rudd they are made here in Arkansas.


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## ralph perrello (Mar 8, 2013)

A heat pump in the A/C mode is not as efficient as a straight A/C.
If your system is nearing 10 years old replace the whole system.
Install a high efficiency furnace and A/C and you will be far ahead financially as the new system will save much on fuel costs.


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## Harry Chickpea (Dec 19, 2008)

ralph perrello said:


> A heat pump in the A/C mode is not as efficient as a straight A/C.
> If your system is nearing 10 years old replace the whole system.
> Install a high efficiency furnace and A/C and you will be far ahead financially as the new system will save much on fuel costs.


You are incorrect. A heat pump in AC mode IS an AC.

A heat pump will also beat out a high efficiency furnace unless fuel costs are significantly lower than electric costs.


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## Sawmill Jim (Dec 5, 2008)

davel745 said:


> heat pumps are only good for temps to 40 degrees F


I think some don't understand a thing called balance point :shrug:


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## Clod Kicker (May 7, 2012)

Here's a good explanation of the balance point> http://www.energyvanguard.com/blog-...ng-Balance-Heat-Pump-Heating-Load-vs-Capacity


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## wannabechef (Nov 20, 2012)

40 degrees or less and heat pumps suck.., I use kerosene when its really cold.

Sent from my GT-P3113 using Tapatalk


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## Harry Chickpea (Dec 19, 2008)

C K, the web link is good as far as it goes. What it doesn't take into account is that manytimes the HVAC ductwork is not within the envelope of the living space.

The problem is easily explained by an extreme example. Farmer Jones has a barn 200 feet from his home. He wants to heat his home using the free heat that his cattle give off in the barn. He runs a 24" insulated duct outside in the snow between house and barn. The air leaving the barn is at 90 degrees, but is always the temp of the outside air by the time it gets to the home. He gets disgusted and runs a salamander heater directly into the duct (which miraculously doesn't melt). The air is STILL at outside air temp when it gets to the home. Obviously, the insulation on the duct is not enough to keep up.

The output of our heat pump goes into ducts under the home. Like a lot of manufactured housing, there is some insulation on the vapor barrier under the home, but the space where the ducts run is still far cooler in winter than the interior. One duct run is about 75 feet. The air coming out of those registers is colder than the air in the room.

I don't obsess about it, but just close off those registers and use space heaters there. The heat that was in the duct isn't a total loss, since it both warms the floors a little and keeps pipes from freezing under the home.

My point is that "balance point" calculations often do not properly take into account losses through ductwork in non-heated areas. In those situations there comes a point that using the heat pump IS less efficient that shutting it down or setting it to a level just high enough to keep pipes from freezing. The better insulation in the envelope of the living space and lack of transfer of air through cold areas will keep the home warmer more cheaply.


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## Clod Kicker (May 7, 2012)

Absolutely correct, Harry. Assuming a Manual J heat loss analysis has been run, the balance point is set to bring on add'l heat below it, and if that add'l heat is working, it all comes back to the installer (who have been known to cut corners).
Another thing to check: proper defrost? If the outdoor unit is a block of ice, it will not perform well.
It is advantageous to set the balance point as low as possible, to keep supplementary heat off as long as possible. Also, limits and controllers on elec. resistance strips burn out often. Being wired in parallel, only one or two out of the set may be working. The only way to check this is with a volt-ohm-ammeter, or multimeter. A clamp-on ammeter would show the total current draw easily, then one matches it to the label on the elec. htg section. 
A better setup is to use gas as a supplement heat. A furnace (Nat. or LP) can replace the elec. ht. section even if it's mounted horizontally. If not high eff. then 4-6" flu pipe is fairly easy to run, assuming one can get the proper rise for draft. A draft inducer (motor and wheel)can be used, but that consumes energy also.
Solution? Make sure everything is working as it should be, then insulate, insulate, insulate!


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## Harry Chickpea (Dec 19, 2008)

I debated a gas furnace rather than heat strips for our home, but the cost of propane was enough then (over $3 per gal) that the heat strips were cheaper to run. What I did instead was add an unvented wall heater, which is more efficient than driving heat through the ductwork and it adds humidity to the home on the coldest days without additional energy usage. (Combustion byproducts are CO2 and H20)


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## bentleywarren (Dec 8, 2013)

michael ark said:


> I like a package units because it's safer over all. If anything goes wrong dead short ,fire etc. it's not happening in the occupied space. In my humble option flex duct is only good to sleeve over hard pipe.


I installed a package unit heat pump about 2-3 years ago and so far I love it. I recognize that it might lose some efficiency because of the long duct system, but what I really love is the quietness. With the air handler motor, fan, etc all mounted outside the house, I hear absolutely nothing inside the house when the system is running.


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## Clod Kicker (May 7, 2012)

An added benefit of the unvented heater is the humidity added to the indoor air, which will help prevent upper respiratory problems and sinusitis due to dry winter air. This can only be done if the unit is listed as "unvented", as clearances are built in to eliminate the possibility of carbon monoxide formation from the flame impinging on metal.
Vent the clothes dryer indoors to do the same, whether it's electric or gas, and gain the heat and humidity that would be wasted outdoors. Use old panty hose at the end of the flex hose to filter the lint out. Be sure to fill the vent to the outside with steel wool first to keep out the meeses, then foam or fiberglas...
eep:​


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