TM 9-2320-260-34-2
17-12. ENGINE COOLANT HEATER TESTING (Contd)
c. Flame Detector Switch Test
1.
Place switch (3) in START position and hold.
2.
When indicator lamp (4) illuminates, place switch (3) in RUN position.
3.
If indicator lamp (4) does not light, adjustor replace flame detector switch (6) (para. 17-3).
4.
Place switch (3) in OFF position.
d. Fuel Control Valve Test
1.
Place switch (3) in START position and hold.
2.
When indicator lamp (4) illuminates, place switch (3) in RUN position.
3.
Check fuel consumption at flowmeter (1). Fuel consumption should be 0.013-0.017 lb/min
(0.006-0.008 kg/min) at low heat, and 0.022-0.030 lb/min (0.010-0.014 kg/min) at high heat. Replace
fuel control valve (7) if fuel consumption rate is not within limits (para. 17-7).
4.
Check operating amperage on multimeter (2). If operating amperage exceeds 4 amperes, check
heater wiring. Replace damaged parts (paras. 17-3 through 17-11, as necessary).
Move switch (5) from LO to HI position. Burning in heater (8) should intensify or decrease. Replace
5.
fuel control valve (7) if burning in heater (8) does not intensify or decrease (para. 17-7).
Place switch (5) in LO position.
6.
Place switch (3) in OFF position.
7.
e. Blower Motor Test
1. Place switch (3) in START position and hold.
2. When indicator lamp (4) illuminates, place switch (3) in RUN position. Allow heater to run for a few
minutes.
a. If blower motor (9) does not run, replace blower motor (9) (para. 17-4).
b. If blower motor (9) runs, but heater does not ignite, check ignition components. Replace ignition
components if defective (para. 17-3, 17-7, 17-8, 17-9, or 17-10).
NOTE
Purge time is the interval from turning control box switch to OFF
position until the indicator lamp goes out.
3. Place switch (3) in OFF position and record purge time. Burning should stop within thirty seconds;
blower motor (9) should continue to run up to three minutes. Replace or adjust flame detector
switch (6) (para. 17-3) if purge time exceeds three minutes.
17-32
