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Thread: FROSTY!!!!

  1. #14
    Join Date
    Dec 2007
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    25
    oh isnt that cute? good place to keep the beer cold

  2. #15
    Join Date
    Dec 2008
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    257
    Quote Originally Posted by KrisAMS View Post
    Heat pumps that far north? I'm in Montreal and we use them all the time. Although it can go as low as -30, we get a lot of days where it is warm enough for a heat pump to work fine. (A heat pump is good until about -12 or 14... then you switch to electric)
    I dont get out much i guess!I didnt think if it snowed it would heat well!it freezes at 28 deg,at 20 deg wouldnt it stay in defrost?We have people complian when its 40 deg here!im sure you use dual fuel!which is not that common here.aux heat 10 to 15 kw.

    last time it got below 20 and snowed was 1984!1 was 8 yrs old!



    Is the average life still 10 to 15 yrs?

  3. #16
    Join Date
    Sep 2004
    Location
    Near New orleans
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    123
    here in the south we have a lot of nat gas so HP are not as common. I could be wrong but -12+ you got to be running off the hest strips not the compresser. it rarely gets below 25 and the heat strips come on all the time. Is there something I am doing wrong??

  4. #17
    Join Date
    Dec 2007
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    37
    I mean -12 to -14 centigrade... I don't know what that is in your system.

  5. #18
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    Apr 2005
    Location
    Tampa, Florida
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    Quote Originally Posted by KrisAMS View Post
    I mean -12 to -14 centigrade... I don't know what that is in your system.
    ~7-10F... well within where heat pumps are still putting out usable heat. Just depends on how they're sized at that point.

  6. #19
    Join Date
    Dec 2007
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    It is perhaps also worthwhile to point out that the heat pump and electric coils can work simultaneously. The heat pump will cycle on alone within a certain indoor temperature deferential which is determined by the thermostat. Likewise, the electric coils will cycle on alone when the outdoor temperature drops below the minimum cut-off set on the heat pump. If the indoor temperature deferential is more than a few degrees and the outdoor temperature is warm enough, then both systems would work simultaneously. Obviously there is still good savings to be had from having the heat pump going whenever possible even if it can't do it alone.

    With regard to the physics of heat, it should be noted that air contains heat even when we might find it really cold. The point at which there is no more molecular activity in air (or anything else) is −273.15°c ... but until that point, heat can be extracted and moved ("pumped") - it is just hard and uneconomical to do so after a certain point.

  7. #20
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    Sep 2002
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    Outdoor thermostats are often used to keep part of the aux heat strips off above a certain outdoor temperature. (Often shown in service/installation manuals)

    In most colder climates I couldn't imagine a heatpump sized for cooling holding the setpoint alone below 32F/0C.
    General public's attitude towards our energy predicament: "I reject the reality of finite resource depletion and substitute it with my own; energy is infinite, we just need an alternative storage medium to run the cars on. The economy can grow indefinitely - we just need to "green" everything! Technology is energy! Peak what?"

  8. #21
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    Dec 2007
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    37
    Heat pumps here are likely sized for heating. Little attention is paid to the SEER for instance - the focus being rather on its heating equivalent.

  9. #22
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    Sep 2002
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    Quote Originally Posted by KrisAMS View Post
    Heat pumps here are likely sized for heating. Little attention is paid to the SEER for instance - the focus being rather on its heating equivalent.
    That must cause humidity problems in cooling mode, unless you live in an area with no cooling season.
    General public's attitude towards our energy predicament: "I reject the reality of finite resource depletion and substitute it with my own; energy is infinite, we just need an alternative storage medium to run the cars on. The economy can grow indefinitely - we just need to "green" everything! Technology is energy! Peak what?"

  10. #23
    Join Date
    Dec 2007
    Posts
    37
    I'm not sure - my thinking would be though that whatever issues might be caused by less efficient moisture removal are far outweighed by the energy savings during the heating period (which is a least twice as long as the cooling period).

  11. #24
    Join Date
    Dec 2008
    Posts
    257
    we dont get alot of cold here!we have mostly h/ps here.elect heat etc.people here will call us about "smoke out of units" on cold mornings,panic when they see ice on coils,some days we will catch 20 calls a day for that!that was what i was going by!i couldnt imagine snowbirds having h/ps!but you size for heat!i get that now.

    boy i do need to get out more often!

  12. #25
    Join Date
    Apr 2005
    Location
    Tampa, Florida
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    Quote Originally Posted by amd View Post
    That must cause humidity problems in cooling mode, unless you live in an area with no cooling season.
    No reason you couldn't get around that little problem with a good multi-speed blower. Drop the CFM, evap temp drops when cooling, dehumidification happens. Set it up to run at full CFMs during heating season. Simple.

  13. #26
    Join Date
    Dec 2007
    Posts
    37
    Back to the pic, I'm a little surprised the new 'old' system even works after being in storage for however many years.

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