Troubleshooting - Bradford White UPV75 Series Service Manual

UPV75 Series - Troubleshooting
Observe green LED indicator on electronic
gas control. Status flash codes are
displayed with a three second pause before
repeating. Check and repair the system as
noted in the troubleshooting table below.
LED Status
None, control
LED not on or No electrical power
flashing
Short flash, once
every four waiting for call for
seconds
Alternates
Thermostat calling
bright/dim
for heat (no fault).
(heartbeat)
Short flash once Weak pilot signal on
per second
Pressure switch not
Two flash, three
second pause
Pressure switch or
Three flash, three blower temp. switch
second pause not working -open
Four flash, three
second pause
Five flash, three Undesired-false pilot
second pause
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Control Status
Control power switch in "OFF" position.
Supply voltage interrupted.
Stand-by mode,
Temperature demand is satisfied.
heat (no fault).
Tank temperature below set point of
thermostat.
Unstable pilot.
1.
Pilot tube block or restricted.
2.
Oxidation build up on pilot electrode.
3.
last call for heat.
Wire damage to pilot assembly or
4.
bad connection at gas valve.
Pressure switch tubing kinked or
1.
blocked.
working- closed Blocked pressure tap on switch or
2.
position. blower.
Faulty pressure switch.
3.
Vent blockage or improper vent
1.
configuration.
Pressure switch tubing kinked or
2.
blocked.
Faulty pressure switch.
3.
Blower not spinning up to speed.
4.
position.
Blower temp or exhaust temp too
5.
high.
Faulty blower temperature switch.
6.
Excessive tank Temperature sensor out of
1.
temperature. calibration.
System must be Faulty gas control.
2.
reset. Plumbing leak.
3.
1. Pilot valve stuck in open position.
flame present.
Probable Cause Service Procedure
Turn power on.
Normal operation. Adjust
thermostat to temp level.
Normal operation. Adjust
thermostat to temp level.
Page 16.
Page 18.
1. Check vent or vent
tables.
2 & 3. Page 18
4. Page 20
5 & 6. Page 24
1 & 2. Replace gas
control, page 28.
Replace gas control,
page 28.
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