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Real World Heat Pump

  1. Nov 15, 2012 #1
    I've been reading a lot, looking for ways to make my heat pump "work less" or more efficiently in the winter months. Since the HP transfers heat... in the winter it's 'taking' heat from outside and moving it inside.. supposedly heating my house.

    Would it be advisable or beneficial (both in out put and energy needed to run the unit) IF I were to encase the outdoor condenser??? shielding it and insulating it.... Maybe even "heating" the encasement?

    If my "outdoor" condenser unit was in "warmer" conditions - wouldn't it have to over come a smaller heating differential between inside and outside? Thus making it run less or more efficiently?

    For my real world example- we are in Mid-Tennessee (yes you may all think Tennessee is "south" and therefore warm, but the winters are cold - just not long).. From Nov-Feb we dip into the low 30s F @ night - and Jan/Feb will see Low 20s or teens - Days are usually in the 40s ...

    SO. Do I build a shed around my condenser? Insulate it and heat it?
    It just seems like having the condenser exposed to the elements is the 'worst' as the temp differential from outside 30F to inside 65F is STILL 35 degrees - it seems the pump is working ALL the time...

    Would the shed idea at least help prevent the frost build up? and therefore the "defrost" mode that incurs using the aux heat.???
  2. jcsd
  3. Nov 15, 2012 #2


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    Staff: Mentor

    If you enclose the condenser, it will quickly cool the enclosure to well below ambient.

    If you heat the enclosure, then you'll be paying for heat the environment provides you for free.

    A few suggestions:
    -Make sure the airflow is unobstructed. This improves heat transfer and reduces frost.
    -Switch to natural gas on very cold days.
    -Spot heat occupied rooms.
    Last edited: Nov 15, 2012
  4. Nov 15, 2012 #3
    thx Russ...

    - 1 by airflow - i assume you mean airflow around the outside condenser

    - 2 - gas is not an option - I'm rural, and electric is all i have.

    - 3 - I don't know what you're driving at with "spot heat occupied rooms".

    So if I understand this correctly - it's a closed system.... if I enclose the outside 1/2, then it would quickly become a refrigerator (like), and have no heat to grab...
    I guess my thought is (and this may be simply a human perception of 'cold' - that 32F is too cold to get heat from...

    Thanks again for the reply
  5. Nov 15, 2012 #4


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    Staff: Mentor

    No prob....

    -Yes, airflow through the heat exchanger in the outside condenser.

    -By "spot heat" I mean using a small, portable electric heater to heat just where you are.

    -No matter how cold it is outside, the condensing unit coil is going to be colder. It has to be in order for the outside air to heat it up.
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