Mendota GREENBRIAR M-50, Installation & Operating Instruction Manual

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INLET
PRESSURE TAP
MANIFOLD PRESSURE
TAP
GAS PRESSURE REQUIREMENTS
ONE MAJOR CAUSE OF OPERATING PROBLEMS WITH GAS APPLIANCES CAN BE IMPROPER GAS
PRESSURE!
Problems such 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 pres-
sure 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 pressure regulator is then placed outside
the residence, near the gas meter, 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 Fireplace, an additional "inches to inches" regulator must be installed for the Fireplace.
EXCEPTION: Some codes allow 2-PSI (1.4KPA) supplies to enter the residence, in which case "pounds to inches" regu-
lators 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" W.C.
(2.61 kPa)
3.5" W.C.
(0.87 kPa)
0 - 1/8 " OPEN
(3 mm)
L.P. GAS 11.0" W.C .
(2.75 kPa)
11" W.C.
(2.75 kPa)
13.0" W.C.
(3.24 kPa)
10.0" W.C.
(2.5 kPa)
1/4" OPEN MIN.
(5 mm)
TURN GAS VALVE HI-LO KNOB TO "HIGH" POSITION. GAS PRESSURES MAY VARY PLUS OR MINUS 5%.
* NOTE: For high altitude (above 2.000 feet) some variations in air shutter settings may be required.
Manifold pressure must be taken at the “MANIFOLD PRESSURE" tap and inlet pressure at the "INLET PRESSURE" tap
with the burner operating by a qualified installer.
Figure 10: Pressure Test Port