13
6. The
burner
seems to
cycle on and
of
f more than
it should.
7. The
burner
starts, but the
main fan
never comes
on.
• Gas manifold pressure
• Dirt on main air blower or improper setup
of outlet air duct
• Burner Control Switch
• Blower motor relay
• Current overload on blower motor
• Blower motor
• Fan switch
• Use a low pressure gauge (0-15 inches of water column) with 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. Refer to pipe
sizing charts in the Heat W
agon Engineering Guide. Heater requires 9-14”
W
.C. inlet pressure.
• 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 (0-15 inches of water column).
• On the main ternimal block, check for 120 volts between terminals 6 and the “C”
terminal on the burner switch, when the 3-position switch is in the Heat position.
Then between terminal 6 and the “1” terminal on the burner switch. If there is
power on the “C” terminal and not at the “1” terminal, replace the switch.
• T
urn the 3-position main switch to the fan position. If the relay pulls in, check
for voltage between the L1 and L2 terminals.
Then check the voltage between
terminals
T1 and
T2.
The voltage should be the same. If it is much lower
,
replace the relay
.
• T
urn the 3-position main switch to the fan position. Check for voltage between
the 2 solenoid coil terminals on the relay
. If there is no voltage, the overload is
bad. Push the reset on the overload.
• T
urn the 3-position main switch to the fan position. Check for voltage between
terminals
T1 and
T2 on the motor relay
. If the voltage is good, replace the
motor
.
• If the blower works with the 3-position switch in the fan position. Replace the
fan switch.
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 ...
