In January we had a new Trane XL15i heat pump professionally installed. I have noticed the system short cycling a few times while heating. The furnace fan stays on, the compressor fan stops then starts again within about 15 seconds. Sometimes the compressor fan will continue running for 5-10 minutes. Sometimes the compressor fan shuts off after a few seconds (usually followed by a loud bang). All the time the furnace fan is still running. Also I get large vibrations throughout the house when the system is doing this.
I checked the "Compressor off time" setting on the VisionPro IAQ thermostat. It was set to "0" so I changed it to the default of "5" minutes. This didn't change anything. The compressor fan still occassionally short cycles. When it does this it usually stops after about an hour and the Aux. Heat (LPG in our case) comes on.
The system normally runs fine with a 10-15 minute run time where both fans turn off simultaneously at the end. This odd behavior only happens now and then.
We are coming to the end of the heating season and I want to have this looked at before it warms up if something is wrong. Is this normal behavior?