Condenser Unit Not Working Properly

by Steve Hailey
(Charlotte, NC)

I've had a contractor (selected by my warranty company) come out and replace the evaporator coil in my air handler because there was a leak.

I've now noticed the system not working properly. The air is cool coming from registers, but the temperature differential between registers and return is only about 3-5 degrees.

The contractor hooked up gauges to the condenser unit and realized the needle on the red gauge(not sure if color coding is universal) was fluctuating between 200 and 450. He stated that needle should remain constant at approximately 300 (not sure what this measures). The other gauge(blue) measured temperature and said it was not reading correctly either.

Contractor is returning today with a water hose to spray at the condenser unit. He believes cleaning the outside could help with this issue. The compressor is running just seems to be running erratically. Will cleaning the unit only, potentially cause the compressor and condensing coil to work properly?