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Heating & Air Conditioning

heat pump blows cold air

15 years ago

I have a goodman heat pump . It blows cold air on start up in the heat cycle . Is there a delay for the evap motor to stay off for a minute? Or does the aux heat supposed to turn on first? When condensor turns off the the evap(inside) fan shuts off too.Shouldn't it run for a minute after the outside unit has turned off.I know some about heat pumps and how they work (about enough to get me in trouble) the schematic doesn't list some of the parts on it , like a sequencer but it seems to test fine.Thank you for any help

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Comments (4)

garyg
15 years ago
I have the fixed speed ARUF374316 air handler for my Goodman GSH14036 heat pump. The Installation and Operating Instructions have a seperate sheet of paper titled "Supplimental Insert, Electronic Blower Time Delay Relay, B13707-35".

There is a 7 second delay for the air handler fan to start after the condenser starts. There is a 65 second delay for the air handler fan to continue to run after the condenser shuts off. This TDR is currently operating properly on my system.

Note that heat pumps require a certain amount of run time to reach optimal output temps. Even with a functioning TDR, I still get "cool" air for the first few minutes.

The palm of your hand is about 91F, so any air at or near that temp will feel cool.

Take care.
broant
Original Author
15 years ago
What I notice is the air handler fan and the outside fan or comp unit turn on at the same time so Im assuming that the delay must not work. It also shuts off at the same time.I dont believe its labeled a tdr but it does identify a type of delay relay. According too the wiring diagram it leads to a regular dp relay.It does have a set of sequencers which delay time but I replaced it with a similar one and nothing changed. They also dont have them on the wiring diagram.thanks for the response.
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"We don't have a furnace, we have a boiler." You saved me the trouble sue of explaining that! OK, what you have is an aqua stat that controls the fan in your air handler. When the t stat calls for heat either a pump comes on or a zone valve opens downstairs and allows 180 degree water to flow through the coil in your air handler. On the hot water pipe that leaves the coil should be a thermostat attached to this pipe. When it senses the water is hot enough going back to the boiler it brings on the blower. That thermostat, known as an aqua stat should be set at 140 degrees. Thats the temperature the fan comes on. The fan off setting is usually 100 degrees. Yours is probably set to low. Check the aquastat settings, there may be 2 settings (on and off) or there may be just 1 and a differential. If its that one set it at 140 with a 40 degree differential. The nice thing about a system like yours is you can fine tune them. If 100 degrees feels to cool you can tweek it up a few degrees to find something more to your liking. You don't have to worry about overheating the equipment. Just don't adjust the two settings to close together or else the blower my cycle on and off to ofter before the t room stat is satisfied
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dadoes
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garymunson-2008
15 years ago
older units didn't usually have the delay timer module, newer ones do.....

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