TM 3-4230-218-30&P
(b) Depress START BURNER switch S1. Check continuity
across terminals 3 and 4 using a multimeter.
If continuity
does not exist, replace switch S1.
(c) Do not press pushbutton on START BURNER switch S1.
Check continuity across terminals 1 and 2. If continuity
does not exist, replace switch S1.
(d) For START BURNER button S1 replacement refer to page
2-62.
(3) Thermostat S3 (High Temp).
Thermostat S3 has contacts that remain closed until the water
temperature at outlet water assembly goes above 120°C. The
contacts then open to stop burner ignition.
To determine if
thermostat S3
is faulty, proceed as follows:
(a)
(b)
(c)
(d)
(e)
Remove front panel (page 2-64).
Turn thermostat selector switch S2 (9) to 120°C position.
Temporarily disconnect thermostat S4. Ensure that conti-
nuity exists across terminals 1 and 2 using a multimeter.
If continuity exists, proceed to next step; if no, check
thermostat selector switch (page 2-62).
At temperature under 120°F, check for continuity between
terminals 3 and 12.
If continuity does not exist; replace
switch S3.
For thermostat S3 replacement refer to page 2-68.
(4) Thermostat S4 (Low Temp).
Thermostat S4 has contacts that remain closed until the water
temperature at outlet water fitting goes above 45°C. The
contacts then open to stop burner ignition.
To determine if
thermostat S4 is faulty, proceed as follows:
(a)
(b)
(c)
(d)
Remove front panel refer to page 2-64.
Turn thermostat selector switch to 45°C position.
Disconnect thermostat S4 from temperature selector switch
S2. Ensure that continuity does not exist across terminal
1 and 2 on switch S2.
If continuity does not exist, pro-
ceed to next step.
If continuity does exist, check ther-
mostat selector switch (page 2-62).
Reconnect thermostat S4 terminals to temperature selector
switch S2.
2-63
