Installation Instructions Comfort Bridge Models

42
MeasurIng Inlet gas Pressure (alt. MetHoD)
fIgure 63
note: wHen conVertIng froM natural gas to l.P.
consult Your DIstrIButor for ProPer conVersIon
kIt.
Range Nominal
Low Stage 1.6 - 2.2" w .c. 1.9" w .c.
High Stage 3.2 - 3.8" w .c. 3.5" w .c.
Low Stage 5.7 - 6.3" w .c. 6.0" w .c.
High Stage
9.7 - 10.3" w .c.
10.0" w .c.
Manifold Gas Pressure
Gas
Natural
Propane
gas InPut rate MeasureMent (natural gas onlY)
The actual gas input rate to the furnace must never be
greater than that specied on the unit rating plate. To
measure natural gas input using the gas meter, use the
following procedure.
1. Turn OFF the gas supply to all other gas-burning
appliances except the furnace.
2. While the furnace is operating at high re rate, time
and record one complete revolution of the gas meter
dial, measuring the smallest quantity, usually the dial
that indicates 1/2 cu. ft. per revolution. You will use
this number to calculate the quantity of gas in cubic ft.
if the furnace would consume if it ran steadily for one
hour (3600 seconds).
Only small variations in gas pressure should be made by
adjusting the gas valve pressure regulator. The manifold
pressure must be measured with the burners operating.
To measure and adjust the manifold pressure, use the
following procedure.
1. Turn OFF gas to furnace at the manual gas shutoff
valve external to the furnace.
2. Turn off all electrical power to the system.
3. Outlet pressure tap connections:
White-Rodgers 36J54 valve: Back outlet pressure
test screw (inlet/outlet pressure tap) out one turn
(counterclockwise, not more than one turn).
4. Attach a hose and manometer to outlet pressure tap .
5. Turn ON the gas supply.
note: follow tHIs ProceDure to test tHe gas ValVe
Pressure at 100% fIrIng rate.
run HIgH fIre
note: tHe coolclouD PHone aPPlIcatIon Be useD to assIst
wItH all functIonal tests. see tHe quIck start guIDe sectIon
for DetaIls.
The furnace should be inspected by a qualied installer, or
service agency at least once per year. This check should
be performed at the beginning of the heating season.
This will ensure that all furnace components are in proper
working order and that the heating system functions
appropriately. Pay particular attention to the following
items. Repair or service as necessary.