18-CD29D1-11
33
Installer’s Guide
NOTE:
The manifold pressure must be referenced to the burner
box. The burner box pressure tap equalizes the gas valve
pressure regulator. Manifold pressure is checked by in-
stalling a tee (field supplied) in the tubing, between the tee
coming from the burner box tube and the gas valve, in ad-
dition to the regular gas valve pressure tap on the outlet
side of the gas valve. See Figure 55.
▲
CAUTION
!
Replace manifold pressure tap threaded plug and leak
check after checking/ adjusting manifold gas pressure.
Table 19 lists the main burner orifices used with the fur-
nace. If a change of orifices is required to correct the fur-
nace input rating. Refer to Table 20.
TABLE 17
FINAL MANIFOLD PRESSURE SETTINGS
MODEL
FUEL
PRESSURE
NATURAL GAS
LP GAS
*UH1B040A9241A
3.5" W.C.
11.0" W.C.
*UH1B060A9361A
3.5" W.C.
11.0" W.C.
*UH1B080A9421B
*UH1C080A9601A
3.5" W.C.
11.0" W.C.
*UH1C100A9481A
*UH1D100A9601A
3.5" W.C.
11.0" W.C.
*UH1D120A9601A
3.3" W.C.
11.0" W.C.
*DH1B040A9241A
3.5" W.C.
11.0" W.C.
*DH1B065A9421A
3.0" W.C.
9.5" W.C.
*DH1C085A9481A
3.5" W.C.
11.0" W.C.
*DH1D110A9601A
4.5" W.C.
11.0" W.C.
5. Adjust gas heat by removing the adjustment regulator
cover screw.
a. To increase outlet pressure, turn the regulator ad-
just screw clockwise.
b. To decrease outlet pressure, turn the regulator ad-
just screw counterclockwise.
c. Adjust regulator until pressure shown on mano-
meter matches the pressure specified in Table 17.
1. The input of no more than nameplate rating and
no less than 93% of the nameplate rating, unless the
unit is derated for high altitude.
d. Replace and tighten the regulator cover screw se-
curely.
6. Cycle the valve several times to verify regulator set-
ting.
a. Repeat steps 5-6 if needed.
7. Turn off all electrical power to the system.
8. Remove the manometer and flexible tubing and tighten
the pressure tap screw.
9. Using a leak detection solution or soap suds, check for
leaks at the pressure outlet boss and pressure tap test
screw.
10. Turn on system power and check operation of the
unit.
▲
WARNING
!
SAFETY HAZARD
Replace and/ or tighten all plugs removed or loosened
when adjusting gas pressure. Leak check the fittings be-
fore placing the furnace into regular service.
Failure to follow this warning could result in fire, explo-
sion, or property damage.
T
Содержание ADH1B040A9241A
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