Brant Radiant Heaters QTD Series User Instruction page 37

QTD Series
Bypassing any switch is intended for testing purposes only. Do not leave switch bypassed
NOTICE
*
during normal operation or the heater's built-in safety mechanisms will be compromised.
Start
Question
Is there 120V on the
common side of the
fan relay?
No
Find source of electrical problem
between the outlet and low fire relay.
Is there 24V across
the circuit board with
terminal to ground?
Check for loose wiring or restrictions
in the hose connections to pressure
switches. Are they OK?
No
Replace wiring or hose connections.
Key
Corrective
Process
Action
Question
Yes
The fan relay is faulty and
Yes
No
Yes
5.0
Is there 120V on the
N.O. side of the fan
relay?
No
must be replaced.
Repair faulty wiring.
Replace the pressure switch after verifying:
• Heater, fan blowers ,squirrel cage, intake
and exhaust are clean and free from dirt and
obstructions.
• The 4" air intake pipe does not exceed 30 ft. and/or
2 elbows.
• There is not a negative pressure experienced at
the area of air intake (e.g.; high winds, attic space,
tightly sealed building). May vary for agricultural
buildings (consult factory).
37
Maintenance • Troubleshooting Guide
Yes
The blower assembly
is faulty and must be
replaced.
Check both high temperature spark
wires and both electrodes. If good,
replace circuit board.