Page 2 of 4 FirstFirst 1234 LastLast
Results 14 to 26 of 52
  1. #14
    Join Date
    Apr 2004
    Posts
    7,680
    I doubt it.

    The warmer air as it cools will increase the relative humidity.

    Based on that, you might still be oversized. 73 degrees at 103 outside means cycling as soon as it cools down to just hot (as opposed to equator hot. This leaves for high humidity forcing you to run the thermostat down for comfort.

    Originally you posted it will not keep 70 on a 90+ day. Now it holds close at 103. Your OP stated that it doesnt run as much as the other one...

    Lets see your load calculation.

  2. #15
    Join Date
    Apr 2004
    Posts
    7,680
    We can use the square footage as a rule, I live in 2600 sqare feet and have a 3 ton.

  3. #16
    But do you live where it's 90+ and 100 and + all summer with humidity like here? This adds to the load which increases the need.

    This morning the humidity did go down to 50% in here but now it is back up to 66%. I have two combination thermometer / hygrometers at each end of the house.
    Right now they are both saying 74 while the thermostat (a White-Rogers Digital Programmable Auto model) is showing 72. It of course is in the hall right under the return.
    The air being delivered to the supply vents is presently 64 degrees. It's 100 or so outdoors.

    This system does generally run less than the old one did.
    On days like today though they perform pretty much the same. This one possibly catches up quicker after sundown and it cools back off some outside. Last night it did not catch up and start cycling again until around 1am. Will probably do likewise tonight. It has been running continuously since 11 this morning.

    This is not a brand new system btw. It was placed into service on 7-31-02 so it is almost three years old now.
    The guys who installed it (and did a bang up job in my estimation) got tired of me complaining and feel that I make much ado about nothing. The Rheem people just say to keep the filter changed and the unit clean and I should be in good shape.

    I went out this morning in search of a checker to do the wb measurements and was told it was only available locally at a place that requires a license to buy parts from them.
    They said to just pay someone come out and test it.

  4. #17


    I went out this morning in search of a checker to do the wb measurements and was told it was only available locally at a place that requires a license to buy parts from them.
    They said to just pay someone come out and test it. [/B][/QUOTE]


    Just take a normal digital thermometer, wrap the tip with a thin piece of tissue paper (perferably toilet paper), wet it, and hold it in front of the return register. Then repeat the steps and hold the thermometer in front of the supply register. This will give wet-bulb temperature.

  5. #18
    Thanks

    wb-return = 64
    wb-supply = 55

    Incidentally it ran until 3am catching back up this morning.


  6. #19
    Join Date
    Apr 2004
    Posts
    7,680
    Yeah it pretty much stay between 90 and 100 here all summer and thick as a brick.

    What's bothering me is the change in humidity in your house from day to night with an insgnificant change in indoor temperature.


  7. #20
    Join Date
    Apr 2004
    Posts
    7,680
    And whats the dry bulb temps?

  8. #21
    Join Date
    Apr 2004
    Posts
    7,680
    Are you running any ype of exhaust fans or attic fans that might be casusing an air change? Has the return been inspected in the attic?

    You got outside air getting into the home somehow, thats my best guess.

  9. #22
    The return was inspected. They told me when they put the system in that we surely did not want any attic air getting into the works.

    I have noticed something that happens every time. When the supply air temperature goes up the humidity goes up and then when it comes back down the humidity comes back down. Does that make any sense? If it is a day where the supply air temp doesn't change much the humidity doesn't either.

  10. #23
    Join Date
    Apr 2004
    Posts
    7,680
    Are you running the fan continuously? If so...STOP IT.
    What are the dry bulb temps?



    [Edited by docholiday on 07-23-2005 at 09:40 AM]

  11. #24
    No, I don't run the fan continuously. When the thermostat kicks on the air the condensor comes on first and gets the coil cold and then the fan comes up gradually. When the thermostat kicks it off the condensor shuts down and then fan stays on for 45 seconds and then shuts off gradually.

    Dry bulb supply = 57
    Dry bulb return = 66


  12. #25
    Join Date
    Aug 2002
    Location
    Office and warehouse in both Crystal River & New Port Richey ,FL
    Posts
    18,836
    Originally posted by ms7168
    No, I don't run the fan continuously. When the thermostat kicks on the air the condensor comes on first and gets the coil cold and then the fan comes up gradually. When the thermostat kicks it off the condensor shuts down and then fan stays on for 45 seconds and then shuts off gradually.

    Dry bulb supply = 57
    Dry bulb return = 66


    Are you sure ,return 66?

  13. #26
    Yes, I didn't believe it either. But that was this morning. Right now it's 100 outside with a 68 dewpoint and my dry bulb supply = 64 and my dry bulb return = 73

Page 2 of 4 FirstFirst 1234 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event