High And Low Pressure Switch Clutch Latching Circuit; Background - New Holland T8010 Manual

Section 50 - Climate Control - Chapter 1

High And Low Pressure Switch Clutch Latching Circuit

Background

High pressure switch activation is generally caused
by a restriction or clog on the high pressure side of
the system. However, a refrigerant or SP-20 PAG oil
overcharge, the presence of refrigerants other than
R134A or engine cooling problems can also cause
high pressure switch activation.
RD02H031
High Pressure Switch at Compressor
Low pressure switch activation is generally caused
by low refrigerant level resulting from a leak(s).
Sometime low pressure switch activation, however, is
caused by a restriction, where because of the
location either pressure switch may activate first. For
example, a restriction at the output of the receiver-
drier could cause either high or low pressure switch
activation.
Refer to the A/C Troubleshooting Foldout and
performance testing to locate the cause for your
system.
When either pressure switch opens within the smart
RD02G096
Low Pressure Switch at Expansion Valve
pressure counting conditions, a fault code displays
o n t h e I n s t r u m e n t C l u s t e r D i s p l ay, a n d t h e
compressor clutch is latched OFF by the controller.
50-1-39