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  1. #27
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    No.

    Given the same unit on the same structure, the balance point would be the same in Texas as it would be in Canada.


    Quote Originally Posted by richper View Post
    B. I have to disagree here Sir . Balance point would be a variable based on both the available total heat content in the outside air conditions and influenced by the variable load on the space to be conditioned.

    That said Sir , how can we call this a fixed setting . ? Moreover. The heat pumps balance point setting would be very different in a warmer climate than a much colder one . Right ?

    I guess what I'm saying is . It would take less added btu's to bring the space to setpoint in Florida , because of a lessening rate of heat loss in the structure, than let's say a structure in Canada , where the wind chills and such are factoring in to the equation of heat loss at a much faster rate from the space being conditioned .

    So , I would say that in the south my balance point, defrost board settings, etc , would be set differently.

  2. #28
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    Richper,

    You are probably thinking of design temps. Or something like heating days versus cooling days. Balance point for a heat pump is when the system capacity and load are equal.

    So, for example, if there is no wind, then that temp will be the same wherever you are. Now if you're in Florida, it's possible that the balance point will never be reached. But whatever temp that is, it will be the same as in Alaska.

  3. #29
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    As outdoor temps drop, HP BTU output also drops. I don't think thermal balance point is the same regardless of location given the same structure. Outdoor air temps help determine the balance point, in a warmer climate the balance point may be 45 or 50 degrees, while in canada, the balance point could be in the teens. I just covered this material so I think that is a somewhat accurate statement.

  4. #30
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    Ok Sir . I get what you are saying . But . In Texas , I'm setting my balance point very low . Why ? Well . I would think that I'll probably never reach my balance point in a southern climate . If I do . It would be foolish not to let that heat pump run with maybe 5 k.w. back up assistance in say 20 degree outside conditions , and get the structure up to set point in a reasonable amount of time .

    Take the same system , the same structure, and place it in Alaska .
    Now I'm locking out that heat pump at let's say 30 degrees . Turning on my fossil fuel back up , and maintaining comfort conditions .

    So . All I'm trying to say is yes . You are absolutely correct in your definition of balance point . No argument here .

    But . In real life scenarios , we have to consider. How long are we at balance point ? How much heat do we need to sustain comfort ? And finally . When is systems efficiency going to be compromised by a fixed setting when we factor in all the other outside influences that Mother Nature has to offer .

  5. #31
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    Outdoor temperature effects balance point.

    Sent from my XT1585 using Tapatalk

  6. #32
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    You're probably thinking of design temps.


    Quote Originally Posted by psehunter View Post
    As outdoor temps drop, HP BTU output also drops. I don't think thermal balance point is the same regardless of location given the same structure. Outdoor air temps help determine the balance point, in a warmer climate the balance point may be set at 45 or 50 degrees, while in canada, the balance point could be in the teens. I just covered this material so I think that is a somewhat accurate statement.

  7. #33
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    Quote Originally Posted by BBeerme View Post
    You're probably thinking of design temps.
    See pics above. Balance point is outdoor temp at which heatpump output equals heatloss of home. In 2 different climates at 2 temps will have 2 different amounts of heat loss. One will be faster at losing heat than the other, which means the thermal balance points would not be the same.

  8. #34
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    LOL, you don't get to set your balance point.

    You're talking about design temps.


    Quote Originally Posted by richper View Post
    Ok Sir . I get what you are saying . But . In Texas , I'm setting my balance point very low . Why ? Well . I would think that I'll probably never reach my balance point in a southern climate . If I do . It would be foolish not to let that heat pump run with maybe 5 k.w. back up assistance in say 20 degree outside conditions , and get the structure up to set point in a reasonable amount of time .

    Take the same system , the same structure, and place it in Alaska .
    Now I'm locking out that heat pump at let's say 30 degrees . Turning on my fossil fuel back up , and maintaining comfort conditions .

    So . All I'm trying to say is yes . You are absolutely correct in your definition of balance point . No argument here .

    But . In real life scenarios , we have to consider. How long are we at balance point ? How much heat do we need to sustain comfort ? And finally . When is systems efficiency going to be compromised by a fixed setting when we factor in all the other outside influences that Mother Nature has to offer .

  9. #35
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    Correct.

    Note that there is no variable for location or latitude.


    Quote Originally Posted by psehunter View Post
    See pics above.

  10. #36
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    Quote Originally Posted by BBeerme View Post
    Correct.

    Note that there is no variable for location or latitude.
    Right but outdoor temp is a factor, Texas and Canada are 2 different extremes.

  11. #37
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    Given the same unit on the same structure, the balance point will be the same.

    In Texas, maybe that balance point will never be reached. But it still exists at the same temp as it does in Canada.

    Even the information you posted does not say anything about location.


    Quote Originally Posted by psehunter View Post
    Right but outdoor temp is a factor, Texas and Canada are 2 different extremes.

  12. #38
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    Quote Originally Posted by BBeerme View Post
    Given the same unit on the same structure, the balance point will be the same.

    In Texas, maybe that balance point will never be reached. But it still exists at the same temp as it does in Canada.

    Even the information you posted does not say anything about location.
    If 2 different temps are present in 2 different locations the balance point changes, the pics show you that. Location is not relevant, outdoor temps effect heat loss.

    If your statement said 2 identical structures, 1 in canada and 1 in texas were at the same outdoor ambient/humidity etc, than balance points would be the same. Texas has a much different climate than Canada.

  13. #39
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    You're getting closer, but you're not quite there yet. Yes, it is all about temperatures.

    Please show me on your charts where it matters what latitude those temps occur.


    Quote Originally Posted by psehunter View Post
    If 2 different temps are present in 2 different locations the balance point changes, the pics show you that. Location is not relevant, outdoor temps effect heat loss.

    If your statement said 2 identical structures, 1 in canada and 1 in texas were at the same outdoor ambient/humidity etc, than balance points would be the same. Texas has a much different climate than Canada.

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