Results 1 to 11 of 11
  1. #1
    Join Date
    Jul 2011
    Location
    Long Island, NY
    Posts
    3

    Poor air flow new oil furnace and coil

    Had my furnace and ac unit replaced this spring but it seems to take forever to cool the house and has long run times even when the outside temp is below the house temp. The furnace is a Bryant OVM oil furnace (OVMAAB036098AABF) with a Bryant 2.5 ton N coil (CNPVP3017ATAACAA). My return duct is 19x10 with a 16x24 return grill. I’ve since read that coils should be 6 inches above the furnace because of the drain pan on A coils and the instruction manual says “A clearance of 15cm (6”) is required between the bottom of the coil drain pan and the top of the heat exchanger.”
    If the cased coils are sitting on the furnace does this clearance exist? I can’t see the bottom of the pan or the exchanger, but then why mention it in the Installation instructions.
    Does the same problem apply to N coils or are their drain pans shaped differently?
    My house is always dry about 43% RH and I do live in a humid region. I live in a 1000sq ft ranch with full basement where the furnace is located. I’m also concerned with the heating system coming that I will not have enough air flow for the new furnace. Last night with thermostat set at 74 and outside temp of 69 ran for half an hour during one of its cycles. Minimal heat load on house TV, laptop and a few florescent lights.

  2. #2
    Join Date
    Sep 2002
    Location
    I don't know
    Posts
    2,903
    2.5 tons for 1000 sq ft?

    Find another contractor to check everything over.
    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?"

  3. #3
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    34,158
    That begs the question... what is your outdoor unit? New Bryant Puron unit? Old R22 unit?

  4. #4
    Join Date
    Jul 2011
    Location
    Long Island, NY
    Posts
    3
    New Bryant Puron Unit

  5. #5
    Join Date
    Sep 2002
    Location
    I don't know
    Posts
    2,903
    What size? 2.5 tons?
    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?"

  6. #6
    Join Date
    Jul 2011
    Location
    Long Island, NY
    Posts
    3
    Yes 2.5 ton.

  7. #7
    Join Date
    Sep 2002
    Location
    I don't know
    Posts
    2,903
    Don't call the same company back - if they didn't do it right the first time, they aren't going to fix it correctly.
    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. #8
    Join Date
    Jul 2004
    Location
    Massachusetts
    Posts
    6,837
    I've put the attached .pdf on this site at least 100 times so you should have already referenced it but if not, here it is again.

    There could be many things affecting the airflow but in order to know that, one must first know how the system was sized and whether the blower is properly adjusted. Once the airflow is established (the installing company should know how to determine the actual airflow) then the questions about refrigerant charge and/or an inoperative component of the system could be found and addressed. I suspect there is a an issue with either the system or the installation but how you selected the installing company and what they did both prior to the installation as well as during and after the installation are crucial.

    The attached document should help you determine if you've got a good company or a fly by the seat of their pants company that should be de-hired.
    Attached Images Attached Images

  9. #9
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    34,158
    If airflow is low, could be that the variable speed motor isn't set right. Turn the heat on, see how the airflow is with heat. If the same, I'm on the wrong track.

  10. #10
    Join Date
    Jul 2008
    Location
    Rochester NY
    Posts
    4,728
    Quote Originally Posted by BaldLoonie View Post
    If airflow is low, could be that the variable speed motor isn't set right. Turn the heat on, see how the airflow is with heat. If the same, I'm on the wrong track.
    Might it have something to do with the fact 1000 sf ranches have nowhere near 1000 cfm of ductwork?

    Oil furnace. Big missed opportunity for a hybrid. That guy didn't do any favors to you.
    Which makes more sense to you?
    CONSERVATION - turning your thermostat back and being uncomfortable. Maybe saving 5-10%
    ENERGY EFFICIENCY - leaving your thermostat where everyone is comfortable. Saving 30-70%

    DO THE NUMBERS! Step on a HOMESCALE.
    What is comfort? Well, it AIN'T just TEMPERATURE!

    Energy Obese? An audit is the next step - go to BPI.org, or RESNET, and find an auditor near you.

  11. #11
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    34,158
    It would be a bit loud in here if my furnace were set on 1000 CFM! Actually it is on high fire, that's why I have a switch to keep high fire off unless I'm warming the house up 10° when it is below zero!

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