Detroit Radiant Products Company QTS Series - Manual (Page 39)

QTS Series
39
5.0 Maintenance • Troubleshooting Guide
Check to make sure gas pressure is
within minimum and maximum inputs as
indicated on the heater’s rating plate.
Is gas pressure OK?
Check to make sure
gas pressure is within
minimum and maximum
inputs, as indicated
Yes Replace gas valve.
No
Correct problem.
Is the heater properly grounded?
Is the heater’s polarity correct?
No
Yes
With microampmeter, check DC
amperage at flame rods.
Is it 1.0 microamps? (See illustration)
No
Check to make sure both flame
sensor wires are OK and then
replace circuit board.
One or both of the flame sensing rods are faulty or flame is
weak. Check to make sure heater is operating at proper gas
pressure as indicated on the heater’s rating plate.
If needed, replace one or both flame sensing rods.
Yes
Pressure switch may be faulty or there
is a restriction in the exhaust. Remove
restriction or replace pressure switch.
Yes
No
Correct
problem.