Hi.
If the unit has been off for one year and now it is not starting, you may need a gas recharge, or the suction capillary tube attached to the evaporator coil may need replacement which will also require a recharge. In that case the recharge must be done by a technician. Testing gas pressure is also an operation that cannot be done by the user.
Things that you can check before calling the technician:
See if compressor is starting. If compressor is starting and running most of the time but there is no cold, then gas pressure is low and you need a recharge. If the compressor does not start check volts to the compressor relay. If there is voltage, replace the relay. If compressor is trying to start, but there is clicking and humming noise and motor does not start regularly, replace Overload capacitor and starter relay.
Here a diagram:
To get parts or to book a technician call BEVERAGE_AIR - 3779 Champion Blvd. • Winston-Salem, NC 27105 USA • TEL: (336) 245-6400 •
www.beverage-air.com Regards.
Ginko