
SERVICING
38
.
Measuring Inlet Gas Pressure (Alt. Method)
T
O
PR
EVENT UN
R
EL
I
ABLE O
P
E
R
AT
I
ON O
R
EQU
IP
MENT
D
AMAGE, THE
I
NLET GAS SU
PP
LY
PR
ESSU
R
E MUST BE AS S
P
EC
I
F
I
E
D
ON THE UN
I
T
R
AT
I
NG
P
LATE
WI
TH ALL OTHE
R
HOUSEHOL
D
GAS F
IR
E
D
A
PP
L
I
ANCES
O
P
E
R
AT
I
NG.
CAUTION
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 (counter-
clockwise, not more than one turn).
4. Attach a hose and manometer to the outlet pressure
tap (White-Rodgers valve).
5. Turn ON the gas supply.
6. Turn on power and close thermostat “R” and “W1” con-
tacts to provide a call for low stage heat.
7. Measure the gas manifold pressure with burners firing.
Adjust manifold pressure using the
Manifold Gas Pres
-
sure
table shown below.
8. Remove regulator cover screw from the low (LO) outlet
pressure regulator adjust tower and turn screw clock-
wise to increase pressure or counterclockwise to de-
crease pressure. Replace regulator cover screw.
9. Close thermostat “R”, “W1” and “W2” contacts to pro-
vide a call for high stage heat.
10. Remove regulator cover screw from the high (HI) outlet
pressure regulator adjust tower and turn screw clock-
wise to increase pressure or counterclockwise to de-
crease pressure. Replace regulator cover screw.
11. Turn off all electrical power and gas supply to the sys
-
tem.
12. Remove the manometer hose from the hose barb fitting
or outlet pressure tap.
13. Replace outlet pressure tap:
White-Rodgers 36J54 valve: Turn outlet pressure test
screw in to seal pressure port (clockwise, 7 in-lb mini-
mum).
14. Turn on electrical power and gas supply to the system.
15. Close thermostat contacts “R” and “W1/W2” to ener-
gize the valve.
Range
Nominal
Natural
Low Stage 1.6 - 2.2" w .c.
1.9" w .c.
High Stage 3.2 - 3.8" w .c.
3.5" w .c.
Propane
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
Using a leak detection solution or soap suds, check for leaks at
screw (White-Rodgers valve). Bubbles forming indicate a leak.
SHUT OFF GAS AND REPAIR ALL LEAKS IMMEDIATELY!
NOTE:
For gas to gas conversion, consult your dealer for
appropriate conversion.
T
O
PR
EVENT UN
R
EL
I
ABLE O
P
E
R
AT
I
ON O
R
EQU
IP
MENT
D
AMAGE, THE
I
NLET GAS SU
PP
LY
PR
ESSU
R
E MUST BE AS S
P
EC
I
F
I
E
D
ON THE UN
I
T
R
AT
I
NG
P
LATE
WI
TH ALL OTHE
R
HOUSEHOL
D
GAS F
IR
E
D
A
PP
L
I
ANCES
O
P
E
R
AT
I
NG.
CAUTION
1. Remove regulator cover screw from the low (LO) outlet
pressure regulator adjust tower and turn screw clockwise
to increase pressure or counterclockwise to decrease
pressure. Replace regulator cover screw.
a. Close thermostat “R” and “W” contacts to provide a call
for heat.
b. Remove regulator cover screw from the high (HI)
outlet pressure regulator adjust tower and turn screw
clockwise to increase pressure or counterclockwise to
decrease pressure. Replace regulator cover screw.
c. Turn off all electrical power and gas supply to the
system.
d. Remove the manometer hose from the outlet pressure
boss.
e. Remove the 1/8” NPT hose barb fitting from the outlet
pressure tap. Replace the outlet pressure boss plug
and seal with a high quality thread sealer.
WARNING
H
I
GH
VOLTAGE
D
I
SCONNECT
ALL
ELECT
RI
CAL
P
O
W
E
R
AN
D
SHUT OFF GAS SU
PP
LY
BEFO
R
E SE
R
V
I
C
I
NG O
R
I
NSTALL
I
NG.