MACH
®
Gas-Fired Boiler
Dual Fuel (NG & LP) MACH Boiler Supplement
4
1.0
Dual Fuel MACH
®
Boilers
This manual describes the installation requirements of the Harsco Industrial, Patterson-Kelley MACH
®
dual fuel
boilers. While details may differ slightly, basic operation is the same for all models. This boiler is built to operate with
natural gas (NG) or propane (LP).
This boiler has been constructed by the factory and shipped as a dual fuel boiler. It is
essential
to read, understand,
and follow the recommendations of this manual before installing, operating, or servicing this equipment. Failure to do
so could result in serious injury, death, and/or property damage.
Each MACH
®
dual fuel boiler is equipped with two current switches: one switch is in the natural gas valve circuit and
the other is in the propane gas valve circuit. These switches are wired in such a manner as to prevent both fuels from
being fired at the same time. In the unlikely event that both fuel valves are open at the same time, the current
switches cause a high gas pressure error which will shut both gas valves and force a manual reset lock-out of the
ENVI™ control.
2.0
MACH
®
C-750GG / C-900GG / C-1050GG DUAL FUEL BOILERS
2.1 G
AS
I
NPUT
C
ONNECTIONS
The MACH
®
dual fuel boiler is equipped with dedicated connections for each fuel. The natural gas (NG) connection is
a 1 1/4” ball valve. The propane (LP) connection is a 1” ball valve. If a fuel connection is not used, it
must
be capped.
It is imperative that the natural gas line be connected to the 1 1/4” connection
and the propane line be connected to the 1“ connection. Incorrect gas connections could result in
serious injury, death and/or property damage.
Do not exceed maximum pressure limits (14” W.C.) for LP & NG fuels.
Installation of the fuel lines must comply with all applicable codes. It is the responsibility of the installer to ensure
compliance with all the requirements of the authority having jurisdiction.
The fuel line ball valves are located on the rear face of the boiler. Each line is labeled for the required fuel. Attach the
propane (LP) line to the 1” ball valve labeled “PROPANE”. Attach the natural gas (NG) line to the 1 1/4” ball valve
labeled “NATURAL GAS”.
It is recommended to close the ball valve for the non-selected fuel.
Use approved pipe sealer that resists the action of fuel gases such as natural gas or propane.
DO NOT USE Teflon™ tape.
Reorder No. 6020-V2WHPK
Improper use may
result in fire or injury.
Read instructions/safety
manual before installing,
operating or servicing boiler.
c
!
WARNING
1998 HCS, Inc. 800-748-0241
