Crown Boiler CWI138 - Manual (Page 40)

40
39
Troubleshooting Chart for CWI Boilers Equipped with Tankless Heaters and Dampers
Caution: Read page 36 before attempting to use this chart
No call for heat,
boiler w ater
temp. at least
20F below low
limit setting
*Pow er off
*Blow n fuse or
tripped breaker
*Misw ired or
loose electrical
connection in
120V line
Vent
damper
open?
24 volts
across B1and
TV on L8124E ?
*Boiler w ater
temp above
low limit
setting
*Defective
L8124E
24 volts
betw een pins
1&4 (blue&yellow )and
2&4 (orange&yellow ) on
damper end of damper
harness? See
Note 7 on page 36.
* Loose
connection
betw een
damper
harness and
L8124E
*Defective
damper
harness.
*Obstruction in
path of damper
blade
*Defective
damper motor
*Loose connection
betw een damper
harness and
damper
Main
burners
light?
24 volts across
gray w ire on
rollout sw itch
and B2?
Y
Refer to standing
pilot or
intermittent
ignition
troubleshooting
chart (page 41 or
42).
START
*Defective damper
*Defective damper
harness
*Loose damper
harness connection
*Obstruction in path
of damper blade
24 volts across
standing pilot gas
valve terminals or
terminals 5&6 on
S8600 module?
24 volts
across spill
sw itch?
*Chimney blockage
*Chimney system not
constructed in accordance
w ith Parts 7 and 10 of
National Fuel Gas Code.
*Dow n draft
*Inadequate combustion air
supply in boiler room
Y
N
N
Y
Y
24 volts
across
rollout
sw itch?
*Loose electrical
connection in 24
volt w iring
betw een rollout
sw itch or B2 and
gas valve or
module
*Rollout sw itch open.
Replace w ith exact
replacement (see parts
list). Check for blocked
heat exchanger.
Y
N
Y
N
N
Y
N
Y
N
Allow boiler w ater
temperature to
reach low limit +
differential setting.
Initiate call for heat
24 volts
across TV
and Z?
120 volts
across L1 &
L2?
N
* Defective
transformer in
L8124E
Y
Y
N
N
24 volts
across TV
& Z?
* Defective
L8124E
Y N