Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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A/C Performance Testing


Performance Temperature Chart:




Performance Temperature Chart:





1. Connect a suitable manifold gauge set and tachometer.
2. Position air temperature controls as follows:
a. Select air conditioner.
b. Position mode selection lever to "Face."
c. Position temperature control lever to "Max" cooling.
d. Position air selection lever to "Recirc."
e. Position blower lever to high.
3. Start engine, then adjust RPM to 1000 with compressor clutch engaged.
4. Vehicle doors should be closed, windows up and engine should be at normal operating temperature.
5. Insert a thermometer in the left center vent and allow engine to run for 20 minutes.
6. Note the discharge temperature and compare with chart. Reading should be taken with compressor clutch engaged.