The cooling fan never shuts off in the cool mode. Worked perfect last summer. Works perfect in the heat mode. The heat pump shuts off and cycles as normal but the room temp isn't maintained in the cool mode. just gets colder. I'm thinking the relay must be stuck or maybe a bad temp sensor.
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Re: fan runs constantly on cool mode
Simple Question: Did you check to see if the fan switch on the
t-stat is in ON or AUTO? If ON the fan runs nonstop. If in auto the fan cycles with the outdoor unit.
next does the fan shut off if you turn the t-stat to off?
A stuck relay should keep the fan running all the time.
Sometimes if the relay is stuck you can whack the side of the Air Handler and the connection will break.
Sometimes instead of a relay there is a stack switch.
It's a little black stack of 3 disks this is a bi-metal switch.
they do get stuck more often than relays.
The fan relay may be on a electronic board. I don't know for sure without seeing your unit.
Good Luck Phil
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n most heat pump thermostats you have two control switches and the temp setting. One control switch will say "Heat", "Off", "Cool" while the other says "On" and "Auto". The three position switch is for whether you are heating or cooling. The two position switch is for the fan control. "On" will make the fan run constantly whenever the three position switch is in HEAT or COOL mode. Some people use this to circulate air at all times. MOST people use the AUTO mode, where the fan is controlled by the circuitry and runs during the times of heating and cooling only.
If you changed the unit but didn't change the thermostat it is possible that the thermostat that you have will not work with that unit. I see that the unit you installed is a heat pump, you may have a straight cool T-Stat. If you put the T-Stat in the "Auto" "Heat" mode the outdoor fan and the compressor should be workng as well as the blower fan. If it turns out that the outdoor fan and compressor are not running you will want to buy a Thernostat that is compatable with heatpumps should be 2 heat/ 1 cool
It is possible that it's the thermostat. When you turn it into cool mode, does the unit come on at all or is it silent? If nothing is coming on, then it's likely it's the tstat. Did the tech check the refrigerant charge while he was there? He should have checked it with the auxillary heat off and the unit just in heat mode. Make sure that the condenser unit outside is coming on when you are calling for cool, If you turn it on and everything comes on, go outside and put your hand on the large copper pipe coming into the unit. In cool mode, this pipe will be cold to the touch and in heat mode, the pipe will be warm to the touch. There isn't much you can do on your own with the exception of changing the tstat. If you can answer some of the questions I have posed, I can try and give you some more answers. Just remember that a check up doesn't mean its a guarantee that something won't happen the next day, it's just that everything was in working order at the time of the checkup.
The blower has absolutely nothing to do with outdoor air. Having the T-Stat set to auto lets the blower come on only when the A/C-heat comes on. With the switch in the ON position the blower simply runs all of the time. Depending on your living space (high ceilings, multi-level) having the blower on constantly while costing a small amount to run can actually save some money and make you more comfortable in the summer. However most people will leave it in auto in the winter so they don't feel as if they have a draft from the air movement as the blower is in high speed in fan on position and cool modes and low speed in heat mode. Many furnaces today are equipped with a setting that allows the blower to run constantly at a lower speed or simply run for a min. or two after the A/C=Heat have turned off.
I just had a new unit installed and I am surfing for troubleshooting tips too. My unit is doing the same... cools well heat sucks. my problem has been isolated down to the reversing valve... It is constantly energised which means it is constantly in a/c mode even when kicking on the heat strips... We disconnected a line at the thermostat and it is working well as a heater now. You may want to check yours to see if it is actually kicking over into to heat mode... -rob
On a furnace the fan is controlled by a computer and a sensor ot a oldstyle fan thermostat. Basically it waits till the furnace heats up a little and then turns it on and after it shuts off it will run till the thermostat cools back down may take a few mins. In cool mode the thermostat controls the fan so it shuts down immediatly. This is why the thermostat asks you if its electric or gas heat. Should have a switch somewhere for this.