30
FIRE, EXPLOSION, ELECTRICAL SHOCK
HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
Gas supply MUST be shut off before disconnecting
electrical power and proceeding with conversion.
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
!
WARNING
NOTE
: For the 2--stage furnaces with a Series J and Series G gas
valve (see Fig. 41),
they MUST have both regulator springs
replaced and the gas valve MUST be pre--adjusted.
For older model 2--stage furnaces with a Series E gas valve (see
Fig. 42), they DO NOT need to have the regulator springs
replaced in the gas valve, but the regulators in the gas valve must
be pre--adjusted for natural applications.
For J and G valves See Fig 41.
1. Be sure main gas and electrical supplies are turned OFF.
2. Remove both regulator seal caps. (See Fig. 41.)
3. Remove both regulator adjustment screws.
4. Remove both Propane gas regulator springs (white).
5. Install natural gas regulator springs (silver).
6. Install regulator adjustment screws.
7. Turn low--heat stage adjusting screw clockwise (inwards)
9.5 turns. This will increase the manifold pressure closer to
the low--heat set point.
8. Turn high--heat stage adjusting screw clockwise (inwards)
12 turns. This will increase the manifold pressure closer to
the high--heat set point.
9. DO NOT install regulator seal caps at this time.
For E valves see Fig 42.
1. Be sure gas and electrical supplies to furnace are off.
2. Remove caps that conceal adjustment screws for high--
and low--heat stage gas valve regulators. (See Fig. 42.)
3. Turn low--heat stage adjusting screw (3/32--in. [2 mm] hex
Allen screw) counter clockwise (outwards) 1 full turn.
This will decrease the manifold pressure closer to the nat-
ural low--heat set point.
4. Turn high--heat stage adjusting screw (3/32--in. [2 mm]
hex Allen screw) counter clockwise (outwards) 2 full
turns. This will decrease the manifold pressure closer to
the natural high--heat set point.
5. DO NOT install regulator seal caps at this time.
A05196
Fig. 41 -- 2--Stage J or G Valve
ON
O
F
F
ON/OFF
SWITCH
INLET
PRESSURE
TAP
BURNER ENCLOSURE
REFERENCE PRESSURE TAP(2-STAGE
AND VARIABLE-SPEED, CONDENSING
FURNACES ONLY)
MANIFOLD
PRESSURE
TAP
LOW-HEAT
ADJUSTMENT
ALLEN SCREW
(UNDER CAP)
HIGH-HEAT
ADJUSTMENT
ALLEN SCREW
(UNDER CAP)
PLUG BUTTON
(2-STAGE AND
VARIABLE–SPEED,
NON–CONDENSING
FURNACES ONLY)
A01069
Fig. 42 -- 2--Stage E Valve
REMOVE LOW GAS PRESSURE SWITCH
FIRE, EXPLOSION, ELECTRICAL SHOCK
HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
Gas supply MUST be shut off before disconnecting
electrical power and proceeding with conversion.
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
!
WARNING
1. Be sure main gas and electric supplies to furnace are off.
2. Remove low--gas pressure switch, brass street 90
_
elbow
and 2--in. brass nipple from the gas valve inlet pressure
tap. (See Fig. 41.)
