Install Instructions

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PVCG-C
Installation, Operating & Service Manual
13 Troubleshooting
A. Before Troubleshooting
The following pages contain troubleshooting
tables for use in diagnosing control problems.
When using these tables the following should be
kept in mind:
1. This information is only meant to be used by
a professional heating technician as an aid in
diagnosing boiler problems.
2. Where applicable, follow all precautions
outlined in the Section 10 (Start-up and
Checkout) of the boiler installation manual.
3. In general, these tables assume that there are
no loose or miswired electrical connections.
Before using these tables inspect all electrical
connections on the boiler to make sure that
they are tight. Also, check the wiring on the
boiler against the wiring diagram in Figures 9.3
and 9.4. Ensure that incoming 120 VAC power
polarity is correct and that the boiler is properly
grounded. Further, ensure that the control
power supply is 24 VAC (minimum 18 VAC to
maximum 30 VAC) and polarity is correct.
4. All controls on this boiler are tested at least
once in the manufacturing process and a
defective control or component is generally
the least likely cause. Before replacing a
component, try to rule out all other possible
causes.
5. When checking voltage across wiring harness
pins be careful not to insert the meter probes
into the pins. Doing so may damage the
pin, resulting in a loose connection when the
harness is reconnected.
B. If The Display Is Blank
1. Check for 24 VAC on transformer secondary
connections (pink and brown wires). If voltage
across these screws is between 18 and 30
VAC, possible causes include:
• Loose connection in transformer harness
• Defective transformer harness
• Defective boiler control
2. If voltage is less than 18VAC at transfer sec-
ondary, possible causes include:
• Service switch off
• Tripped 120VAC breaker
• Miswired or loose connection in 120VAC
boiler circuit.
• Loose connection between transformer
primary and 120VAC line.
• Defective transformer (possibly caused
by short circuit in 24VAC wiring or addi-
tional loads connected to the transformer
in the field).
C. If Control Shows Err Code
Use Table 13.0 to help identify and correct the
cause of the problem.
D. If Control Shows StA Code, but Other Problem
Present
If no Err Code is observed (even after repeatedly
pressing I to cycle through Operation Mode), use
Table 13.1 to help identify and correct the cause
of the problem.