Instinct
Gas Valve Replacement
3
9. Install new O-Rings in the opening on both sides of
the new Gas valve as shown in Fig. 4.
Fig. 4: Gas Valve O-Ring
10. Secure the gas valve to the bracket with the screws
previously removed.
11. Secure all four screws on both sides of the gas valve
WARNING
!
Ensure the O-Rings are properly seated in both gas
valve opening prior to tightening the screws. Improp-
erly seated O-rings can cause severe personal injury,
death or substantial property damage.
12. Reconnect the Molex plug to the gas valve electri-
cal connection.
13. Check and test all gas connections for leaks. Repair
leaks if found.
WARNING
!
Do not check for gas leaks with an open flame. Use a
bubble test. Failure to check for gas leaks can cause
severe personal injury, death or substantial property
damage.
14. Turn the electrical power “ON” to the boiler to check
combustion.
3. Combustion Test and Adjustments
NOTICE
The installer MUST perform a complete combustion check
to ensure the following combustion levels are met at high
and low input firing rates and the burner is operating at op-
timum conditions.
Table 1: Recommended Combustion Settings
NG
110, 155
NG
199
Propane
H
igh F
ire
CO
2
Range
9.0 to
10.5%
8.5 to
10.5%
10.4 to
11.0%
O
2
Range
4.85 to
2.15 %
5.75 to
2.15 %
5.1 to
4.2 %
CO Max
150 ppm
200 ppm
Lo
w F
ire
CO
2
Range
9.0 to
10.0 %
8.5 to
10.0 %
10.4 to
11.0 %
Lower than or equal to High Fire
CO
2
level
O
2
Range
4.85 to
3.0 %
5.75 to
3.0 %
5.1 to
4.2 %
Higher than or equal to High Fire
CO
2
level
CO Max
10 ppm
WARNING
!
The combustion testing and adjustments must be per-
formed by a qualified installer, service agency or the
gas supplier. All combustion measurements must be
performed with calibrated equipment to ensure prop-
er readings and accuracy.
WARNING
!
Failure to perform a complete combustion test at both
high and low input rates may result in incomplete
combustion and the production of carbon monoxide,
which can cause severe personal injury, death or sub-
stantial property damage.
1. Touch simultaneously on the up and down soft
keys (as high lighted by the wrench icon) for 3 sec-
onds to access the functions for the installer. See
Fig. 5.
