Technical data

0803UDSA-2GBEN, Pag. 35/36
General Troubleshooting
PROBLEM PROBABLE CAUSE REMEDY
1. No power to unit. 1. Turn on power, check supply fuses or circuit breaker.
2. No
p
ower to venter motor. 2. Check connections at burner rela
y
and/or venter motor terminals.
3. Inte
g
rated burner rela
y
defective. 3. Re
p
lace burner rela
y
.
4. Defective venter motor. 4. Re
p
lace venter motor. See Section 26.
5. Fluse blown
(
F3.1
)
.5. Re
p
lace fuse.
6. Fuse burner rela
y
blown. 6. Re
p
lace fuse.
7. LC1 o
p
en. 7. a
)
Set heater on ventilation until LC1 closes.
b
)
Re
p
lace LC1.
c
)
Check if there is obstruction at the fan side.
8. LC3 o
p
en. 8. a
)
Reset LC3.
b
)
Re
p
lace LC3.
9. Unit in lock-out. 9. Push on reset button.
10.Room thermostat o
p
en. 10.Set thermostat above room tem
p
erature.
Burner will
1. Main valve not o
p
eratin
g
.1. a
)
Check volta
g
e on valve durin
g
i
g
nition
p
eriod.
not light
b
)
Check connector on main
g
as valve.
c
)
Check connector on burner rela
y
.
d
)
Re
p
lace valve.
2. Air in the
g
as line. 2. Pur
g
e
g
as line.
3. Gas pressure too high or too low. 3. a) Supply pressure should be 15 mbar for natural gas (UK only) or 37 mbar
for propane gas (UK only).
b) Obstruction in the gas line.
c) Gas line connection diameter too small.
4. No S
p
ark: 4. Check the followin
g
:
a
)
Loose wire connections. a
)
Be certain all wire connections are solid.
b)
Incorrect s
p
ark
g
a
p
.
b)
Maintain s
p
ark
g
a
p
at 3 mm.
c
)
S
p
ark cable has a short circuit to
g
round. c
)
Re
p
lace worn or
g
rounded s
p
ark cable.
d
)
S
p
ark electrode has a short circuit to
g
round. d
)
Re
p
lace if ceramic s
p
ark electrode is cracked or
g
rounded.
e
)
Burner rela
y
not
g
rounded. e
)
Check burner rela
y
g
round wire.
f) Unit not properly grounded. f) Make certain unit is properly field grounded (earthed) and properly phased
(
L1 to hot lead L2 to neutral
)
.
g) Faulty burner relay. g) If voltage is available to the burner relay and all other causes have been
eliminated, re
p
lace burner rela
y
.
5. Combustion air pressure switch 5. First check the following :
not closing upon power to venter. a) Make sure unit is properly vented.
b) Remove obstructions from vent.
c) Replace faulty tubing to pressure switch.
d) Replace faulty pressure switch.
Burner cycle
on and off
1. Gas pressure too high or too low. 1. Supply pressure should be 15 mbar for natural gas (UK only) or 37 mbar
for propane gas (UK only).
2. Burner relay not grounded. 2. Check burner relay ground wire connection.
3. Faulty burner relay. 3. If (220/240) volts is available to the burner relay and all other causes have
b
een eliminated, re
p
lace burner rela
y
.
4. Flame sensor grounded. 4. Be certain flame sensor lead is not grounded or insulation or ceramic is
not cracked. Replace as required.
5. Cracked ceramic at sensor. 5. Replace sensor.
6. Incorrect polarity. 6. Check polarity switch and if necessary reverse line voltage wires to
terminal block connections.
1. Circuit open. 1. Check wiring and connections.
2. Defective fan control (FC). 2. a) Replace fan control.
b) Check voltage on anticipation resistor when gas valve is open.
3. Defective motor. 3. Replace motor or starter.
Fan or
venter motor
turns on and
off while
burner is
operating
1. Motor internal thermal protection device
cycling on and off.
1. Check motor load against motor rating plate. Replace motor if needed.
Venter
motor will
not start
Fan motor
will not run