TM 10-3510-220-24
3-19.
WATER HEATER ELECTRIC CONTROL ASSEMBLY (CONT)
TEST (Cont)
8.
Check low water relay (8) as follows:
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
Tag and disconnect wires from terminals 1 and 2 of low water relay (8).
Use multimeter on high ohms scale and measure between terminals 1 and 2. Meter should indicate open.
Measure between terminal 1 aud chassis ground. Meter should indicate open.
Measure between terminal 2 and chassis ground. Meter should indicate open.
If meter indicates continuity for step b. thru d. above replace low water relay (8) (DISASSEMBLY, step
4, and ASSEMBLY, step 8).
Connect wires to terminals 1 and 2 of low water relay (8). Remove tags.
Tag and disconnect wires from terminal 9 and 10 of low water relay (8).
Repeat measurement on terminals 9 and 10 in accordance with step b, thru d. above. If continuity is indi-
cated replace low water relay (8) (DISASSEMBLY, step 4, and ASSEMBLY, step 8).
Connect wires to terminals 9 and 10 of low water relay (8). Remove tags.
Use a multimeter on low ohms scale and measure between terminals 3 and 4 of low water relay (8).
Meter should indicate continuity. If continuity is not indicated, replace low water relay (DISASSEMBLY,
step 4, and ASSEMBLY, step 8).
Turn temperature control to zero. Use multimeter on high ohms scale and measure between terminals 7
and 8 of low water relay (8). Meter should indicate open. If continuity is indicated, replace low water
relay (DISASSEMBLY, step 4, and ASSEMBLY, step 8).
9.
Check alarm (9) as follows:
a.
Close fuel shut off valve on the water heater (TM 10-3510-220.10) to simulate a low fuel and loss of
flame condition.
b.
Ensure that alarm (9) sounds and water heater shuts down.
c.
Open fuel shut off valve and reset water heater (TM 10-3510-220-10).
Change 3
3-87