Friedrich VRP12K, Service And Parts Manual

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158 PB
TROUBLESHOOTING
Required Skills
1. Patience –
Revolutionary digital communicating technology has replaced older analog components.
2. Patience –
Needle point leads will save you time when backprobing molex connectors.
3. Patience –
Know who to call when you need help.
4. Observation –
There are many LED indicators on the MCS and FMC which all correspond to unit operation.
5. Electrical tracing –
24V AC systems have replaced low (5-10V) DC voltage.
6. DC Communication –
The interpretation of values and commands transmitted by VDC.
Probability Diagnosis:
Rule Out:
• The act of ruling out and understanding certain components operation
based on experience
and
simply watching and observing the system operate.
True Certainty Diagnosis:
• The act of understanding how components operate to
maintain their logical sequence of operation
where failure to produce expected results occurs.
• The act of proving a condition exists, or existed, by testing and acquiring physical and empirical
evidence which caused, or is the result, of that condition.
Troubleshooting by Rule Out Methodology