2
1.0 Adjusting the Gas Valve
The FTG 600, FTG 800, FTG 1200 & FTG 1400 are converted from Natural to LP Gas by
adjusting the Throttle Screw located on the gas valve; unlike most LP conversions an LP
orifice is
NOT
used.
1.
Locate the Throttle Screw on the gas valve, see Figure 1-1.
2.
Turn the Throttle Screw all the way in (clockwise until it stops).
3.
Turn the Throttle Screw counterclockwise (out) ½ of a turn (¾ of a turn for FTG 1400).
4.
Proceed to Section 2.0,
Gas Valve and Burner Setup
, for instructions on how to test the Gas Line Pressure and
perform the Combustion Calibration.
Figure 1-1 Gas Valve Assembly
2.0 Gas Valve and Burner Setup
Failure to perform the Gas Valve and Burner Setup correctly may result in incorrect
operation, component failure, property damage, serious injury or death.
Operating Sequence
Prior to commencing the Gas Valve and Burner Setup, perform the following operating sequence check:
1.
Turn the supply of gas to the boiler off.
2.
Set the thermostat to the highest setting.
3.
Ensure the combustion fan pre-purges for at least 30 seconds prior to activating the igniter.
4.
Ensure the combustion fan post-purges for at least 60 seconds prior to reactivating the igniter.
5.
Set the thermostat to the lowest setting and continue with the Gas Valve and Burner Setup procedure outlined
below.
Gas Valve
Throttle Screw
– used to calibrate
combustion at max. modulation rate (use
3 mm
hex wrench). Pre-set by turning
screw all the way in (clockwise) until it
stops, then turn out (counterclockwise) ½
a turn (3/4 of a turn for FTG 1400)
Line Pressure Test Port
(located on gas valve inlet
flange)
Venturi
Combustion Blower
Air Filter
Cap
(remove to access the
Throttle Screw)
Low Gas Pres. Switch
(auto-reset)
High Gas Pres. Switch
(manual reset)
Offset Screw
– used to set
combustion at min. modulation rate;
must remove cap first
(use T40 Torx wrench)
