Air Conditioner Comes On For 10 Seconds Or So And Kicks Back Off Again, Any Ideas?
I have a central air conditioning unit in my ranch-style home (full basement also). Yesterday the AC just kicked off randomly. I checked the thermostat and it seemed to be functioning ok (it's digital). I went downstairs to the power switch dedicated to the central air unit and turned it off, then back on again. The AC kicked back on, stayed on and started blowing cool air, then kicked back off again 2 minutes later. I suspected there was an airflow problem of some type (filter, etc) but that doesn't appear to be case, at least not as far as I can tell. Are there any other common causes for this type of behavior?
Answer:
If it was low on charge, why would it kick back on and blow cold air? If you want to be sure that it's not a control problem, remove the face of the thermostst and install a jumper between the R,G, and Y terminals. If the A.C. runs continually and cools effectively, replace the t-stat. PS: Don't worry, it's only 24volts. Be careful if there is a "C or B" terminal that you don't touch them with the jumper as you could blow a transformer fuse. It's not unusual for me and my guys to add those controls to a contractor grade condensing unit. I also add a head pressure control to those AC systems installed in restaurants since the units are run year round. If there is no electronic thermostat with a built in anti-short cycle timer, an inexpensive timer module installed in the condensing unit can save an expensive compressor from those people who like to play with thermostats. It's often very difficult to convince some folks to spend money on preventive maintenance.