Gas Piping; Gas Valve - York FC9C UP Series Installation Manual

IMPORTANT: Some accessories such as electronic air cleaners and
pleated media may require a larger side opening. Follow the instruc-
tions supplied with that accessory for side opening requirements. Do
not cut the opening larger than the dimensions shown in Figure 1.
All installations must have a filter installed.
SECTION V: GAS PIPING
GAS SAFETY
An overpressure protection device, such as a pressure regulator,
must be installed in the gas piping system upstream of the furnace
and must act to limit the downstream pressure to the gas valve so it
does not exceed 0.5 PSI {14" w.c. (3.48 kPa)}. Pressures exceed-
ing 0.5 PSI {14" w.c. (3.48 kPa)} at the gas valve will cause damage
to the gas valve, resulting in a fire or explosion or cause damage to
the furnace or some of its components that will result in property
damage and loss of life.
INLET
PRESSURE
TAP
ON/OFF
KNOB
FIGURE 2: Gas Valve
IMPORTANT: Plan your gas supply before determining the correct gas
pipe entry. Use 90-degree service elbow(s), or short nipples and con-
ventional 90-degree elbow(s) to enter through the cabinet access holes.
GAS PIPING INSTALLATION
Properly sized wrought iron, approved flexible or steel pipe must be
used when making gas connections to the unit. If local codes allow the
use of a flexible gas appliance connection, always use a new listed con-
nector. Do not use a connector that has previously serviced another gas
appliance.
Some utility companies or local codes require pipe sizes larger than the
minimum sizes listed in these instructions and in the codes. The furnace
rating plate and the instructions in this section specify the type of gas
approved for this furnace - only use those approved gases. The instal-
lation of a drip leg and ground union is required. Refer to Figure 3.
EXTERNAL MANUAL
SHUTOFF VALVE
TO GAS
SUPPLY
GROUNDED JOINT UNION
DRIP
MAY BE INSTALLED
LEG
INSIDE OR OUTSIDE UNIT.
FIGURE 3: Gas Piping
Unitary Products Group
IMPORTANT: An accessible manual shutoff valve must be installed
upstream of the furnace gas controls and within 6 feet (1.8 m) of the fur-
nace.
The furnace must be isolated from the gas supply piping system by
closing its individual external manual shutoff valve during any pressure
testing of the gas supply piping system at pressures equal to or greater
than 1/2 psig (3.5 kPa).
Gas piping may be connected from either side of the furnace using any
of the gas pipe entry knockouts on both sides of the furnace. Refer to
Figure 1 dimensions.
The inlet to the gas valve lines up directly with the opening in the left
side of the furnace casing. To line up with the opening in the right side
of the casing, two street ells should be used.
GAS ORIFICE CONVERSION FOR PROPANE (LP)
This furnace is constructed at the factory for natural gas-fired operation,
but may be converted to operate on propane (LP) gas by using a fac-
tory-supplied LP conversion kit which contains a new gas valve. Follow
MAIN the instructions supplied with the LP kit. Refer to the instructions in the
REGULATOR
propane (LP) conversion kit for the proper gas orifice size.
ADJUSTMENT
HIGH ALTITUDE OPERATION
This furnace is constructed at the factory for natural gas-fired operation
OUTLET
at 0 – 4,000 ft. (0 m – 1220 m) above sea level.
PRESSURE
TAP
At elevations above 4,000 feet, the furnace will automatically reduce it's
input rate if necessary to maintain good combustion. If the natural gas
being supplied has also been derated by the gas supplier, it may be
necessary to increase the orifice size in order to achieve the rated input.
TO GAS
SUPPLY
The gas valve body is a very thin casting that cannot take any
external pressure. Never apply a pipe wrench to the body of the gas
valve when installing piping. A wrench must be placed on the octag-
onal hub located on the gas inlet side of the valve. Placing a wrench
to the body of the gas valve will damage the valve causing improper
operation and/or the valve to leak.
PROPANE
It is very important to choose the correct kit and/or gas orifices for
the altitude and the type of gas for which the furnace is being
installed.
Only use natural gas in furnaces designed for natural gas. Only use
propane (LP) gas for furnaces that have been properly converted to
use propane (LP) gas. Do not use this furnace with butane gas.
Incorrect gas orifices or a furnace that has been improperly con-
verted will create an extremely dangerous condition resulting in pre-
mature heat exchanger failure, excessive sooting, high levels of
carbon monoxide, personal injury, property damage, a fire hazard
and/or death.
Propane (LP) conversions are required in order for the appliance to
satisfactory meet the application.
An authorized distributor or dealer must make all gas conversions.
The installer must take every precaution to insure that the furnace
has been converted to the proper gas orifice size when the furnace
is installed. Do not attempt to drill out any orifices to obtain the
proper orifice size. Drilling out a gas orifice will cause misalignment
of the burner flames, causing premature heat exchanger burnout,
high levels of carbon monoxide, excessive sooting, a fire hazard,
personal injury, property damage and/or death.
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