VIII) TROUBLESHOOTING GUIDE
Robertshaw 2000N WDER and White-Rodgers Intelli-Vent
TM
– 31 –
SYMPTOM
POSSIBLE CAUSE(S)
CORRECTIVE ACTION
BLOWER WILL NOT
START.
1. No Power to unit.
2. Thermostat setting too low.
3. Defective air pressure switch (must be
open at start-up before blower is ener-
gized).
4. Defective blower.
5. Disconnected or loose wire.
6. Control locked-out.
1. Plug in power cord, check fuses/supply
voltage.
2. Increase thermostat temperature set-
ting.
3. Replace air pressure switch.
4. Replace blower.
5. Repair/reconnect wires.
6. Reset – determine cause of lockout.
BLOWER RUNS
CONTINUOUSLY.
1. Air pressure switch not closing due to
insufficient draft - check for:
a) vent piping blocked,
b) piping length too long,
c) frozen vent termination,
d) clogged/dirty blower.
2. Disconnected, torn or blocked pres-
sure sensing tubing from air pressure
switch to blower housing.
3. Air pressure switch not closing due to
defective switch.
4. High limit switch open due to excessive
vent temperature or defective switch.
1. Determine cause of insufficient draft.
Check draft with manometer at pres-
sure switch (refer to Table 2 for mini-
mum acceptable draft settings).
a) remove blockage,
b) reduce vent length/increase vent
size,
c) clear termination of snow/ice,
d) clean blower wheel.
2. Reconnect or replace pressure sensing
tubing.
3. Replace defective pressure switch.
4. Determine cause of overheating check
for: overfiring, insufficient air supply,
high ambient air temperature (once
activated high limit must be replaced).
1. 120VAC polarity reversed at 120VAC
outlet receptacle.
2. Defective hot surface igniter.
3. Defective Control.
1. Reverse polarity at 120VAC outlet
receptacle.
2. Replace igniter (Check for 120VAC
across I1 & I2, Robertshaw only).
3. Replace control.
CONTROL LOCKED-OUT.
1. No gas supply.
2. Gas control switch in “OFF” position.
3. Insufficient gas supply.
4. Incorrect manifold gas pressure.
5. Incorrect gas type.
6. Defective igniter/loose or disconnected
wire.
7. Improperly positioned, dirty, or defec-
tive flame rod/loose or disconnected
wire.
8. Burner orifice clogged.
9. Blocked water heater flue.
10.Defective control.
1. Check/turn on gas supply.
2. Turn control switch to “ON” position
(Robertshaw only).
3. Ensure correct supply pressure for gas
type (Nat Gas 7.0 in. w.c. (1.74 kPa))
(Propane 11.0 in. w.c. (2.74 kPa)).
4. Check/adjust for correct manifold gas
pressure (NG 3.5 in. w.c.(0.87 kPa)),
(Propane 10.0 in. w.c. (2.49 kPa)).
5. Ensure correct gas type for water
heater model.
6. *Replace defective igniter/reconnect
wiring.
7. *Reposition, clean, or replace defective
flame rod/reconnect wiring.
8. Remove obstruction.
9 Remove blockage/clean flue.
10.Replace Control.
* See Figure 24 Parts Reference
CONTROL LOCKED-OUT.
*SOLID GREEN LED.
1. Internal control fault.
2. ECO failure – excessive water temper-
ature.
3. Excessive humidity/damp environ-
ment.
1. Replace control.
2. Replace control.
3. Allow control to dry.
HOT SURFACE IGNITER
NOT GLOWING
FOLLOWING WARM-UP
PERIOD.
