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APPENDIX A - CONTROL MODULE
A.6 Boiler High Limit Temperature Controller
• When water temperature reaches setpoint, controller
ends heating cycle.
• When water temperature drops below setpoint minus
differential, controller restarts heat cycle to re-heat
boiler water.
• If water temperature exceeds maximum allowed
temperature (220°F or 104°C), controller enters manual
reset lockout state.
• For models having reset capability, press any onboard
button or cycle power to reset.
A.7 Troubleshooting
• Following service procedures are provided as general
guide.
• On lockout and retry models, meter readings between
gas control and ignition module must be taken within
trial for ignition period. Once ignition module shuts
off, lockout models must be reset through key buttons
and display. On retry models, wait for retry or reset at
thermostat.
• Check for correct installation and wiring before replacing
any component.
• Control module cannot be repaired. If it malfunctions, it
must be replaced.
•
Use only qualified service agent to service ignition
systems.
1.
Perform checkout as first step in troubleshooting.
Check troubleshooting guide to pinpoint cause of
problem. See Table A7.
2.
If troubleshooting indicates ignition problem, see
Ignition System Checks to isolate and correct the
problem.
3.
Perform checkout procedure following troubleshooting
guide again to verify system is operating normally.
A.8 Troubleshooting Error Codes
Integrated boiler control uses advanced diagnostic
capability to assist in troubleshooting error conditions.
Table A7 shows codes that could arise on integrated display
during fault.
Suggestions are provided in Table A1 page 34 and Table A7
for servicing these potential errors.
Figure A-2 - Basic Control Algorithm Example
PN 240012809, Rev. C [11/15/2020]
