Owner's manual

24
No
Problem 6
Heater does not
return back to
low heat.
Does
main burner decrease
in heat
when thermostatic head is
set below room
temperature?
Remove thermostatic head from modulating valve assembly:
A. If heater returns to low fire when you push down on plunger pin of valve, Replace
thermostatic head/sensor assembly.
B. If heater still does not cycle to low fire, the modulating valve is sticking and
should be replaced.
Heater
backflashes
gas through
air housing.
Problem 5
Is inner
cone seam
fractured or is tip
damaged or
missing?
Replace combustion cone.
Yes
No
Are
air housing. venturi
tube, burner
orifice,filter, or inner
cone partially
plugged with
dirt?
Clean these
components.
No
Is proper
gas pressure
supplied to
the heater?
Check for proper
gas pressure.
Proper pressure at
high heat should
read 5 PSIG.
Yes
No
Combustion Cone Kits
Part
Number
21087
Yes
Are burner
assembly
nuts loose?
Yes
Tighten the nuts
Is the burner
plate or burner
gasket cracked?
Yes
Replace the burner
plate.or gasket
No
No
Is inner cone
weld seam
aligned to
burner plate
notch?
No
Position the inner cone
weld seam in burner plate
notch.