Installation Guide

Part number 550-100-066/0608
g a s -f i r e d w at e r b o i l e r — Boiler Manual
86
Troubleshooting (continued)
U-Control display toggles when in lockout, with screen flashing red to gray
  
Manual reset limit open Set if manual reset limit open Reset with manual reset on control
Heat exchanger temp high Set if either the heat exchanger outlet or inlet is higher than 200f Reset with manual reset on display
Supply water too fast Set if supply water too fast has occurred 5 times since last power cycle Reset with manual reset on display (also resets 5 times counter)
Supply > return by 58 °F Set if supply > return has occurred 20 times since last power cycle Reset with manual reset on display (also resets 20 times counter)
Temperature sensors Hx inlet or outlet, or flue sensor is open or shorted Reset with manual reset on display
Flue temperature high Set if flue temp > 220 °F Reset with manual reset on display
Flame fault Flame detected when there should be no flame (actual flame or flame detect circuit hardware fault) Reset with manual reset on display
Ignition fault Set if more than 5 ignition retries Reset with 1 hr auto reset – OR – with power cycle
Hardware fault Set if issue with flame detect hardware (could see dual fault here - flame and hardware)
Ram check fails or rom check fails
Reset with manual reset on display
Gas valve fault Occurs if hardware controlling the gas valve does not open
or close during the ignition sequence as expected within allotted time.
Reset with manual reset on display
Blower fault Occurs if there is rpm feedback when blower should be off during ignition sequence.
Occurs if rpm cannot be control to within +/-100rpm before ignition.
Occurs if there is no rpm feedback during ignition sequence.
Reset with manual reset on display
Lwco fault Set if open more than 1 second Reset with manual reset on display