Reznor LDAP Unit Installation Manual - Manual (Page 13)

Form I-LDAP, P/N 207733R6, Page 13
CAUTION: DO NOT
bottom out the gas
valve regulator
adjusting screw.
This can result
in unregulated
manifold pressure
causing excess
overfire and heat
exchanger failure.
FIGURE 7 - Top View of Valves showing Outlet Pressure Tap
and Adjustment Locations
Single-Stage Valve
1/8” Output
Pressure Tap
Adjust Low
Pressure Output Adjust
High
Pressure
Output
1/8” Output
Pressure Tap
Inlet
Pressure
Tap
Inlet
Pressure
Tap
Two -Stage Valve (optional on
Model LDAP 400 only)
Output
Adjustment
Screw
NOTE: If operating at
high altitude, outlet
pressure requires
adjustment. Follow
instructions below.
adjustment is necessary, remove the cap from the adjustment screw(s). Set
pressure to correct settings by turning the regulator screw IN (clockwise)
to increase pressure. Turn regulator screw OUT (counterclockwise) to
decrease pressure.
3) If installing a Model LDAP 800, repeat to verify outlet pressure on second
valve. If installing a Model LDAP 1200, repeat to verify outlet pressure
check on second and third valve.
NOTES: If installation
is above 6000 ft
(1830M), a high altitude
pressure switch is
required on each heat
section (all sizes). See
Paragraph 3.3.
The main combustion
air pressure switch
(Sizes 800 and 1200
only) does not need to
be changed for high
altitude installation.
Derate by Valve
Outlet Pressure
Adjustment for High
Altitude Operation
Manifold Pressure Settings by Altitude for the UNITED STATES
Altitude Natural Gas (inches w.c.) Propane Gas (inches w.c.)
Feet Meters
Single-Stage and
Two-Stage High Fire
Two-Stage
Low Fire
Single-Stage and Two-
Stage High Fire
Two-Stage
Low Fire
0-2000 0-610 3.5 2.0 10.0 5.6
2001-3000 611-915 3.1 1.7 8.8 5.0
3001-4000 916-1220 3.0 1.7 8.5 4.8
4001-5000 1221-1525 2.8 1.6 8.1 4.6
5001-6000 1526-1830 2.7 1.5 7.7 4.4
6001-7000 1831-2135 2.6 1.5 7.4 4.2
7001-8000 2136-2440 2.5 1.4 7.1 4.0
8001-9000 2441-2745 2.4 1.3 6.7 3.8
9001-10000 2746-3045 2.4 1.3 6.7 3.6
Manifold Pressure Settings by Altitude for CANADA
Altitude Natural Gas (inches w.c.) Propane Gas (inches w.c.)
Feet Meters
Single-Stage and
Two-Stage High Fire
Two-Stage
Low Fire
Single-Stage and Two-
Stage High Fire
Two-Stage
Low Fire
0-2000 0-610 3.5 2.0 10.0 5.6
2001-4500 611-1373 2.8 1.6 8.1 4.6
Instructions for High Altitude Derate
1. Determine the required valve outlet pressure for the elevation where the
heater will be operating. If unsure of the elevation, contact the local gas
supplier.
Valve Outlet Pressure Settings by Elevation
2. Locate the 1/8” output pressure tap on the first valve (See FIGURE 7). Turn
the knob on the top of the valve to “OFF”. Connect a manometer to the 1/8”
pipe outlet pressure tap in the valve. Use a water column manometer that
is readable to the nearest tenth of an inch.
3. Single-Stage and Two-Stage High Fire - Turn the knob on the top of the
valve to “ON”. Remove the cap from the pressure adjusting screw and
adjust the gas train pressure to the pressure selected from the table above.