A/C runs for 1 minute then stops for 3 minutes, and so forth

[walter kanov]

I have a strange problem that has been bugging me for a long time that i am finally trying to resolve :wall: . It is hard to explain, so please bear with my lengthy "novel" below.

The problem occurs only after the A/C system is has been off for a while (like in Spring when it is starting to get hot outside or when i had it turned off for a day replacing condenser fan motor). It takes the system several days before it starts operating normally.
The symtoms are that inside air blower kicks on, i walk outside and the condenser fan is spinning just fine, small pipe is luke-warm and large pipe outside is cold (and there is water condensing on it). From all that i gather everything works fine, but, after about a minute or two of working, the whole thing shuts off (air blower and the condenser fan). After being off for 3 minutes or so, the same story repeats. After about 20 starts, the A/C will run for 2 minutes instead of 1, after another twenty starts it will manage 3 minutes, etc... So eventually what appers to be normal operation resumes, but it shouldn't be this way, should it?

The outside coils have just been cleaned. The freon pressure has been checked and appears to be normal. I am not sure i want to take inside unit apart to clean/inspect unless i absolutely have to.

I have heard two possible explanations for the problem:
1) thermostat is bad (but wouldn't then the problem stick around for more than a couple of days)
2) too much water condensating somewhere. This sounds more plausible since air is pretty humid in this part of the country, but do 15 year old Rheem 2.5 ton units have any type of protection that would shut down the system in such cases? The water just starts to drip from the drain line on the inside unit when shut down happens.

Could it be something else?

Thanks for advice in advance.

[DNT1]

Sounds like you have a dirty liquid line filter drier and the unit is kicking out on high pressure. Locate the small hot line coming out of the condensor and follow it all the way to the little round can thing now carefully feel of the line before the can thing and after if the after is cooler (it should be the same) you hav a restriction at that point in your systeml Have a tech take the pressures to confirm he can then evacuate and replace the filter drier and clean the expansion device screen and you should be good to go. I would not run the unit until it is repaired the constant kicking out on high pressure can severly shorten the compressors life. plus it is very inefficeint and runs up the electric bill.

[hvac01453]

If you have a condensate pump make sure it's empty when you start it up. It MAY have a safety float switch that opens when the pump fails. You MAY have a freeze stat thats opening too (only if you have a freeze stat sometimes called a freeze protection switch) To test the thermostat remove the cover and jump the red wire and yellow wire together with a small jumper wire. If you have a round honeywell T87F style, it has three small flat tip screws, LOOSEN ONLY about three turns, and then the rest of the way, to remove the stat. They are located at 9, 7,& 3 O'Clock. If electricity scares you this is only 24Volts, you can Kill the furnace to kill the power if the cooling comes through the furnace blower. Put the fan switch to the ON position, make sure it runs the fan first, then power up the furnace after you have your jumper on Red to Yellow, or RC to Y1 (or Y) . If it runs continuous, replace the stat and sub base.