Results 1 to 6 of 6
  1. #1

    take a look at this

    Hi guys ,

    take a look at this diagram . It shows the refrigeration in the cooling mode. I understand that the refrigerant flows from the expansion valve to the evaporator in cooling mode. But what about heating mode ? How will it flow in the reverse direction ie in the heat mode , would the refrigerant flow from the compressor to the evaporator and then to the expansion valves in the diagram , but the refrigerant can only flow from the expansion valve to the evaporator and not the other way ?
    Attached Images Attached Images  

  2. #2
    Join Date
    Apr 2013
    Independence, MO
    This flow chart is for strictly a/c, not heat pump.
    Advice is always free, but keep in mind free does not mean it's always right.

  3. #3
    Join Date
    Apr 2011
    SE Washington
    add in a reversing valve and some piping and viola, heat pump
    Total Energy Management, inc., Carrier Presidents Award 2011, 2012, 2013

  4. #4

    what happens to the evaporator in the heat mode ?

    Quote Originally Posted by isuredo View Post
    add in a reversing valve and some piping and viola, heat pump
    i understand how the reverse valve works,
    however it seems unclear how the refrigerant would move in the heat mode, as it would move from the compressor to the indoor coils and then to the evaporator, as i suppose. But the refrigerant can only move in a single direction in within the evaporator ? So what happens to the evaporator in the heat mode ? Does the refrigeration system have some mechanism of bypassing the evaporator ? So would the refrigerant just move from the evaporator to the check valve and bypass the evaporator in heat mode , like in this diagram ? How does the system make sure that the refrigerant will move from the indoor coil to the check valve for heat mode ?
    Attached Images Attached Images  

  5. #5
    Join Date
    Oct 2008
    In a kitchen with my head stuck in an oven
    No coils (evaporator or condenser/indoor or outdoor/whatever) are or will be bypassed in the refrigeration cycle.

    In one coil the refrigerant MUST condense to a liquid (latent heat is given up by the refrigerant to do that).

    In the other coil the refrigerant MUST evaporate into a vapor (latent heat is absorbed by the refrigerant to do that).

    Each coil is a reversed process of what the other did. It's gotta happen that way. The cycle won't work without both happening.
    Also, the reversing valve DOES reverse the flow through the coils to change the AC cycle into a heat pump cycle. The only component that DOESN'T see a reversal of refrigerant flow is the COMPRESSOR...for obvious reasons.

    "You never know what others don't know." -

    If I can't laugh at myself...then I'll laugh at YOU! -

  6. #6
    Join Date
    Aug 2009
    Prattville, Alabama
    It may help to think in terms of the "indoor coil" and the "outdoor coil", instead of the "evaporator" and the "condenser". That's because both coils' function changes when in the heating mode. In other words, when in "heat" the outdoor coil becomes the evaporator, and the indoor coil becomes the condenser. And just as the air out of the condenser is warmer than the air going into it (on a standard A/C), so is the air warmer coming out of the indoor coil in the heat mode, which is now functioning as the condenser.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Related Forums

Plumbing Talks | Contractor MagazineThe place where Electrical professionals meet.
Comfortech 365