Electrical System Inspection
You can feel for oil at the bottom of all connections (see Figure 7-4) if the
system is not too hot. Of course, a few minutes with an electronic leak
detector is the best way to check for leaks. Keep in mind that pressure is
different in a system at rest, so small leaks may be hard to find. Pressure in a
system at rest, will equalize at from 60 to 95 PSI, depending on outside air
temperature. This means there is more pressure in the low side of the system
at rest than during normal system operation. Just the opposite is true of the
high side; at rest, high side pressure is lower. You may want to use the
detector to check for leaks in the high side when the air conditioner is
operating, if you suspect a leak and can't find it when the system is at rest.
This illustration shows
a potential refrigerant leak
point at the condenser fit-
ting.
Electrical System Inspection
The two stages of an electrical inspection are explained in more detail below:
1. Inspect Electrical Connections
2. Check Electrical Current Flow and Device Functions
Use the following procedures to perform an electrical system inspection:
1. Inspect Electrical Connections
First, while you are making your visual inspection under the hood (cab)
and/or at the roof top condenser, take a moment and check all electrical
connections visually and by feel. Look for any corrosion on leads or
connectors and clean them. Make sure all leads and wires are properly
supported and securely connected.
2. Check Electrical
Current
Flow
and
Device
Functions
Perform the following steps to check current flow and electrical device
functions:
A. Turn the Ignition On -- To check current flow the ignition must
be on.
