Installation Instructions - STA-RITE MAX-E-THERM SR400LP Instructions Pour L'installation

Installation Instructions

Before proceeding with adjustment, verify that the kit
contains all of the parts listed in the Repair Parts List
(Page 4), and that the letter codes stamped on the orifices
correspond to the letter code for your model shown on
Tables 1 and 2, Page 4.
Tools Required
You will need the following tools and instruments to make
this adjustment:
1 Adjustable wrench, 2-1/2" Capacity
1 Adjustable wrench, 1-1/2" Capacity
1 Flat Blade Screwdriver
1 Phillips Screwdriver for enclosure halves
1 7/16" Nut Driver
1 7/16" Wrench
1 3/16" Hex key (Allen wrench)
2 2 Ft. lengths of 1/4" flexible plastic or rubber tubing
2 1/8" NPT barbed fittings
1 Pipe Sealant approved for use with
natural gas or LPG
1 Differential pressure gauge or slope gauge
(inclined manometer) capable of reading to a
resolution of 0.05" W.C. (the
"Low Pressure Gauge")
1 Flue-gas analyzer reading either CO
Do not attempt the orifice replacement without all the list-
ed tools and instruments.
Instructions For Checking the Gas
Pressure Through the Combination
Gas Control Valve
Risk of fire and explosion. Improper installa-
tion, adjustment, alteration, service, or maintenance of
the Combination Gas Control Valve can lead to fire or
explosion, causing loss of life, personal injury, or property
damage.
These instructions are for the use of qualified service tech-
nicians only!
Do not attempt this procedure unless you have been
trained and certified in the care and repair of gas-fired
appliances!
Do not attempt this procedure if you find the following
instructions confusing!
This appliance is equipped with an unconventional gas
control valve that is factory set with a manifold pressure of
–.2" wc. Installation or service must be performed by a
qualified installer, service agency, or the gas supplier. If this
control valve is replaced, it must be replaced with an iden-
tical control.
The combination gas valve incorporates dual shut-off
valves and a negative-pressure regulator. For proper opera-
tion, the regulated pressure at the outlet manifold of the
valve must be 0.2" wc below the reference pressure at the
blower mixer inlet, and the gas valve 'VENT' tap must be
connected to the mixer inlet as shown in Figure 1 (right).
Figure 1: Vent Valve Tap Connection To Mixer Inlet
Do not attempt to adjust the gas input by adjusting the reg-
ulator setting. The regulator is factory set to maintain prop-
er combustion and must not be altered.
Verify the maximum and minimum regulated gas pressures
or O .
2 2
from the gas supply. These pressures must be within the
range listed on the conversion plate.
Supply Verification Procedure:
1. Turn off the electrical supply to the heater; turn off the
2. Unbolt and separate the top jacket halves (see
Figure 2: Separate Jacket Halves
3. Use a 3/16" hex key to remove the plug from the
2
NOTICE:
The gas piping and
unions have been omitted for
clarity; make this test with all
gas piping connected (as for
normal service).
To Air Flow
Switch
pump; turn off the manual gas supply valve to the
heater.
Figure 2).
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'PRESSURE TAP' port on the outlet side of the
Combination Gas Control Valve.
Connection for
Test
To High Side
of Differential
Pressure Gauge
Vent
Press
Tap
To Low Side of
Differential
Pressure Gauge
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