Paloma PH2-20R DVSN, Engineering Handbook

Page: 65 / 172

SVC 820-Tankless Gas Trouble Shooting Manual Page | 65
65
33 – Error Code Diagnostic Chart
Check the resistance across 2 black wires
on bottom Molex:
7k – 23K Ohms
Clean Scale Build-Up on Outlet Thermistor.
Retest Thermistor. IF tests OK, the water
heater appears to be normal. Attempt to
operate unit again. IF resistance NOT OK:
Replace Outlet Thermistor
Replace wiring harness for Connector “R”
on Control Board
NO
YES
YES
NO
Is the resistance
to the Outlet
Thermistor OK?
Is the continuity
across all wires
OK?
Remove Molex from Connector “R” at Control Board.
Check continuity from black #3 wire at Connector “R”
Molex and black wires at black Molex located behind
Control Board. Check continuity from red #4 wire at
Connector “R” Molex and red wire at Black Molex
located behind Control Board
Attempt to operate unit again.
If the unit malfunctions due to an Error Code 33:
Replace Control Board