Mendota SEABROOK D-30, Installation & Operating Instructions Manual

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17
GAS PRESSURE REQUIREMENTS
A MAJOR CAUSE OF OPERATING PROBLEMS WITH GAS APPLIANCES CAN BE IMPROPER GAS PRESSURE!
Such problems as changes in flame color or configuration, gas pilot or burner outages, intermittent operation, changes
in heat output, excessive burner noise, etc. are nearly always the result of changes in gas pressure or improper gas
pressure at the time of the installation. The most important item to check during the installation and the first thing to
check when problems occur is gas pressure!
Gas supplies normally enter a residence at 1/2 PSI [13" - 15" W.C.] [3. KPA]. A regulator is then placed inside the
residence, which drops this pressure to 7" W.C. [1.8 KPA] [Nat. Gas]. This "inches to inches" regulator is of adequate
capacity to service the gas appliances (such as dryer, furnace, etc.). If this regulator's capacity is not sufficient to add
the Gas Insert, an additional "inches to inches" regulator must be installed for the Insert. EXCEPTION: Some codes
allow 2 PSI [1.4KPA] supplies to enter the residence, in which case "pounds to inches" regulators are used.
The following table provides information on correct gas pressure requirements. Be sure your gas supplier or plumber
carefully follows this table.
GAS PRESSURE REQUIREMENTS
DESIRED
INLET
PRESSURE
MINIMUM
INLET
PRESSURE
MAXIMUM
INLET
PRESSURE
MANIFOLD
OUTLET
PRESSURE
AIR SHUTTER
POSITION
NATURAL GAS 7.0" W.C.
(1.75 kPa)
5.0" W.C.
(1.12 kPa)
11.0" W.C.
(2.61 kPa)
3.5" W.C.
(0.87 kPa)
1/8" - 1/4" OPEN
(7 mm)
L.P. GAS 11.0" W.C.
(2.75 kPa)
11.0" W.C.
(2.75 kPa)
13.0" W.C.
(3.24 kPa)
10.0" W.C.
(2.5 kPa)
1/2" OPEN
(14 mm)
TURN GAS VALVE KNOB TO "HIGH" POSITION. GAS PRESSURES MAY VARY PLUS OR MINUS 5%
1/8" Brass pressure tap fittings are located on the main gas valve. Manifold pressure must be taken at the "OUT”
tap and the inlet pressure at the "IN" tap
with the burner operating by a qualified installer.
[See FIGURE 11 Pressure Test Port].
FIGURE 12: Pressure Test Port
L.P. AND NATURAL GAS SUPPLIES
The Mendota Gas Insert is available for either L.P. or Natural Gas. A Natural Gas to LPG conversion kit is supplied
with the unit.