Manifold Pressure Adjustment - Lochinvar 000 - 500 Installation And Service Manual

FIG. 17 Wrench
8. For L.P. gas, consult your L.P. gas supplier for
expert installation.
IMPORTANT
Upon completion of any piping con nec tions to the
gas system, leak test all gas con nec tions with a soap
solution while system
Immediately repair any leaks found in the gas train
or related components.
appliance with a leak in the gas train, valves or
related piping.
GAS MANIFOLD PRESSURE
ADJUSTMENT PROCEDURE
Pressure Regulator Adjustment
(under cap screw)
Manometer
4
3
2
1
3.5"
0
1
2
3
4
FIG. 18 Manifold Pressure Adjustment
is un der pressure.
Do Not
op er ate an
Gas Valve
1. Turn the power "OFF" at the main dis con nect
switch.
2. Turn gas valve control knob to "PILOT" po si tion
on standing pilot models. Ensure that the stand ing
pilot remains on. If the pilot goes out, follow the
"Lighting Instructions" for standing pi lot models
to light the pilot. Turn gas valve control knob to
"OFF" po si tion on spark ignition models.
3. Remove the 1/8" hex plug located on the out let
side of the gas valve and install a fitting suitable to
connect to a manometer or magnahelic gauge. See
Figure 18. Minimum range of scale should be up
to 5" w.c. for Natural gas mod els and 10" w.c. for
L.P. gas models.
4. The 500,000 Btu/hr model will have two gas
valves with a pressure regulator on each valve.
Repeat the following adjustment pro ce dure to set
the manifold pressure on each gas valve.
5. Remove pressure regulator adjustment cap screw
on the gas valve. See Figure 18 for location.
6. Turn the power "ON" at the main dis con nect
switch.
7. Turn gas valve control knob to "ON" po si tion.
8. Set the thermostat(s) to call for heat.
9. Observe gas regulator pressure when all burn ers
are firing. See Table D, Manifold Pressure for
proper regulator pressure settings.
10. If adjustment is necessary, turn regulator
ad just ment screw clockwise to raise regulator gas
pres sure, counterclockwise to lower gas pres sure,
to proper setting.
plas tic and may require slightly greater turning
force than a metal fitting.
11. Turn the power "OFF" at the main dis con nect
switch.
Do not increase regulator pres sure beyond specified
pressure setting.
12. Turn gas valve control knob to "PILOT" po si tion
on standing pilot models. Turn gas valve control
knob to "OFF" position on spark ignition models.
13. Remove fitting from the gas valve and re place the
1/8" hex plug that was previously removed and
tighten.
15
Note: Adjustment fitting is
NOTE: