Gas Pressure Adjustment; Air Flow Adjustments; Gas Valve Setup And Adjustment - Patterson-Kelley MACH C1500 Installation And Owner's Manual

MACH® Series Gas-Fired Boiler

3.12.3 Gas Pressure Adjustment

Note: Adjustments shall only be performed by
qualified and knowledgeable installer or service
agency specifically trained and certified to perform
maintenance and/or startup on the Patterson-
Kelley MACH® boiler.
See rating plate for the minimum and maximum gas
pressure of the boiler. Each boiler is furnished with a
manual shut-off valve which has an integrated test
port.
This port is located on the upstream side of the valve
body for measuring supply pressure. (See figure
below.)
The supply pressure during main burner operation
must be greater than the minimum indicated on the
rating plate which is 3" W.C. for natural gas. Nominal
gas supply pressure is 7" W.C. for natural gas. The
gas pressure must not exceed 14" W.C. which is the
maximum allowable pressure on the gas train
components.

3.12.4 Air Flow Adjustments

The air flow is pre-set at the factory prior to shipment.
In unusual situations the air/gas ratio may have to be
Gas Pressure Test Port
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adjusted to obtain proper combustion readings for
specific local conditions.
Combustion measurement instrumentation must be
used to adjust the boiler for local conditions (See
instructions below). Adjust the carbon dioxide (CO
or oxygen (O ) reading to achieve conditions as listed
2
in the following Table 3-1.

3.12.5 Gas Valve Setup and Adjustment

Note: Verify gas pressure at inlet to boiler is in
accordance with Table 3-1 below. Gas flow is
dependent primarily on fan speed not upstream gas
pressure. When set up for natural gas operation, the
boiler is capable of operating with gas supply pressure
as low as 3" W C.
Boiler Test Mode:
The test mode should be used when checking and
setting the gas safety shut off / control valves on the
MACH® C1500/C2000 boilers. In this mode an
automatic heat request is simulated as follows:
Test Mode High:
Simultaneously pressing the "Mode" button and the
"+" button for 3 seconds activates the "Test Mode
High" function to drive the boiler output to maximum.
The display will blink and indicate "H" in the first
digit of the display to indicate the boiler is being
driven to the maximum output rating.
This test mode will automatically terminate after 15
minutes or can be terminated from the control/display
panel by simultaneously pressing the "+" and "-"
buttons for three seconds.
Test Mode Low:
Simultaneously pressing the "Mode" button and the
"-" button for 3 seconds activates the "Test Mode
Low" function to drive the boiler output to minimum.
The display will blink and indicate "L" in the first
digit of the display to indicate the boiler is being
driven to the minimum output rating. This test mode
will automatically terminate after 15 minutes or can be
terminated from the control/display panel by
simultaneously pressing the "+" and "-" buttons for
three seconds.
Installation
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