User Guide

79
FIGURE 14.4: LOCKOUT/HOLD CODES
Code Meaning Possible Causes/Remedies
0 No hold or lockout present
47 Flame rod to ground leakage
• Damaged ame rod
• Blocked condensate drain
• Shorted or mis-wired ame rod wiring
49 Voltage supplied to control is outside of acceptable range.
• Line voltage supply to boiler is outside acceptable range.
• Defective transformer
• Bad connection between transformer and control.
50 Control modulation parameters are incorrectly set.
If this is seen after restoration of parameters from PIM (Appendix C), attempt to restore a second time. If
problem persists replace control.
61
Boiler is waiting for anti-short cycling (ASC) time to pass before
starting ignition sequence.
Normal operation if anti-short cycle time (ASC) is not set to zero. Indicates that required time has not yet
elapsed between last call for heat and this one. Boiler should respond to call for heat when this time has
passed.
62 Waiting for fan to reach pre-purge/ignition speed. Normal when fan is ramping up to pre-purge speed. Should clear after a few seconds.
63
One of the following limits is open:
1. Auxiliary limit
2. Thermal fuse
3. Sump pressure switch
• Look for open external limit or, if none is installed, loose/missing external limit jumper
• Check continuity directly across thermal fuse and replace heat exchanger if none is
present. Also see text.
• Blockage in vent or intake system.
65 Waiting for air proving switch to close during pre-purge Normal Hold during pre-purge. Should clear after a few seconds.
66 Air proving switch (APS) is closed when it shouldn’t be.
• Jumped APS
• Defective or incorrect APS.
• Loose connection between terminal J2 and DC fan plug
67 Flow switch not closing.
• Air in heat exchanger (bleed as shown in Figure 11.1)
• Inoperable boiler pump
• Undersized boiler pump
• Air in system
• Excessive pressure drop in boiler loop (P/S piping not used when it should be)
79 Supply water temperature exceeded 210F
• Defective pump or inadequate boiler water ow (see causes for error code 67).
• Heating load far below boiler’s minimum ring rate
• No ow through system loop
81 Temperature rise across boiler exceeded 63F Inadequate water ow through boiler (see causes for Error code 67).
82 Flue gas temperature exceeded 214F
• Dirty heat exchanger
• Incorrect air-fuel ratio
• Excessive ring rate.
85 Return temperature is higher than supply.
• Boiler pump or connections to boiler are reversed.
• Supply/return sensor wiring reversed
• Supply or return sensor is defective
88 Supply temperature climbing too quickly. • See causes for error code 79
91 Inlet (return) sensor fault
• Break in sensor wiring
• Short in sensor wiring
• Check for defective inlet sensor using the resistance table 14.8a.
92 Outlet (supply) sensor fault
• Break in sensor wiring
• Short in sensor wiring
• Check for defective inlet sensor using the resistance table 14.8a.
95 Stack sensor fault
• Break in sensor wiring
• Short in sensor wiring
• Check for defective inlet sensor using the resistance table 14.8a.
105 Flame signal detected when no ame should be present.
• Defective gas valve (verify inlet pressure is less than 14.0” wc before replacing)
• Electrical noise.
110 Burner failed to light or ame not detected.
• Gas valve switch turned off (80-120 only)
• Inadequate gas pressure
• Gas line not completely purged of air
• Incorrect air-fuel ratio (CO
2
)
• Loose gas valve connection
• Defective or dirty ignition/ame rod electrode
• Loose or defective ignition cable
• Loose ame rod connection
• Plugged condensate drain
• Loose burner ground connection
• Defective gas valve (check for 24VAC across red and yellow leads at gas valve plug during trial for
ignition before replacing)
122, 123 Fan failed to reach correct ignition speed.
• Loose or miswired fan harness
• Loose J2 Plug
• Loose connection in 120V fan wiring
• Defective fan
136 Air proving switch (APS) failed to close during last pre-purge.
• Blockage in vent or intake system
• Abnormal air or ue gas restriction through boiler (e.g. fouled heat exchanger)
• Closed outlet tapping on gas valve
• Loose or blocked hose between APS and gas valve
137 Flow switch failed to close during last cycle. • See causes for error code 67
173, 177
Gas valve output error (power detected at control’s gas valve
output when none should be present)
Verify wiring is correct, then reset control. If problem persists replace control.
All other
codes
Various Reset control. If problem persists, replace control.