TM 10-4520-259-13&P
k.
With multimeter on high ohms scale measure between terminal 2 and chassis ground. Meter should
indicate an open circuit.
l.
If meter indicates continuity during i., j., or k. above replace low water relay (3) as described in
removal g. and install j.
m. Reconnect tagged wires to terminals 1 and 2 of low water relay (3). Remove tags.
n.
Tag and disconnect wires from terminals 9 and 10 of low water relay (3).
o.
Conduct measurements on terminals 9 and 10 as described in paragraphs j., and k., for terminals 1 and
2. Meter should indicate continuity. If continuity is not indicated, replace low water relay as described in
removal. g. and install j.
p.
Turn temperature control to zero. With multimeter on high ohms scale measure between terminals 7
and 8 of low water relay (3). Meter should indicate an open circuit. If continuity is indicated, replace low water
relay as described in removal g. and install j.
NOTE
Turn power on before testing.
q.
Test function of alarm (4) by closing the fuel shut off valve on the water heater to simulate a low fuel
and loss of flame condition. If alarm does not function, disconnect power and replace buzzer as described in
removal paragraphs k. or 1. and installation e. or f.
M-85
r.
Test the K-2 initiate relay (6-1-9976/6-1-8786) by checking for continuity between pin 2 and 7. Meter
should indicate low resistance.
s.
Check for closed contacts between terminals 5 and 8, and 1 and 4. Meter should show 0 ohms.
t.
Check for open contacts between terminals 5,6 and 8, and 1 and 3. Meter should read infinity.
u.
Replace relay if these readings are not obtained.
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