10
1. T
urn
the
heater to
position #1
and nothing
happens.
2. The
heater
runs for a little
while, but
shuts down. It
won’t come on
again until I
reset the limit
switch.
• Power supply cord
• Burner lock out on the burner flame
safeguard control box is engaged
• Overheat limit switch is tripped
• 24 volt transformer
• Burner control switch
• Incorrect burner manifold pressure
• Restricted airflow
• Overheat limit switch faulty due to loss of
power
• T
est for 240 volts between terminal #4 and #5 on the main terminal block.
• T
urn thermostat of
f for 50 seconds.
Turn thermostat on
• Reset switch, located on the main control box under the black screw cap .
• Using a volt meter
, check for 24 volts
AC between ground and one of the “T”
terminals on the burner control box. If less than 24 replace transformer
.
• On the main terminal block, check for 120 volts between terminal 6 and the “C”
terminal on the burner switch and then between terminal 6 and the “1” terminal
on the burner
. If there is power on terminal “C” and not on terminal “1” replace
the burner switch.
• Use a low pressure gauge (0-15 inches of water column) with a 1/8” NPT
inlet.
Install gauge in the pressure tap port located on the output side
of the gas valve. Run the heater
.
Adjust the pressure by turning the pressure
adjusting screw (located on the input side top of the gas valve) counter
clockwise until the gauge reads 3.6” W
.C. for propane or 6.1” for natural gas.
• Check for dirt or ice buildup on the air inlet or blower wheel. If using duct on
the air outlet, insure the back pressure does not exceed a static pressure of 2”
W
.C. Check with low pressure gauge if necessary (0-15 inches of water column).
• Adhere to the proper shut down procedures.
Power must remain at the unit until it cools down fully
. Blower will shut down on
its own when cool.
Test overheat limit switch for continuity between the two
male terminals (C and 2) at room temperature. Replace if overheat limit switch
fails test.
V
G
5
00 TR
OUBLESHOO
TING
Symptom
P
ossible Causes
P
ossible Solutions
Summary of Contents for VG500
Page 16: ...16 Burner Parts List ...
Page 17: ...17 Burner Parts List ...
Page 18: ...Piping Connections Cartridge Assembly 18 ...
Page 19: ...19 240 Volt 1 PH ...
