Counterflow Installations; Gas Piping Checks; Propane Gas Tanks And Piping; Ductwork - Maytag Amana MES80 Series Manual

pipe size.
When the gas piping enters through the side of the furnace,
the installer must supply the following fittings starting from
the gas valve:
• Nipple
• Elbow
• Straight pipe to reach the exterior of the furnace.
• A ground joint union, drip leg, and manual shutoff
valve must also be supplied by the installer.

Counterflow Installations

When the gas piping enters through the side of the furnace,
the installer must supply, the following fittings starting from
the gas valve:
• Nipple
• Elbow
• Straight pipe to reach the exterior of the furnace.
A ground joint union, drip leg and manual shutoff valve must
also be supplied by the installer.

Gas Piping Checks

Before placing unit in operation, leak test the unit and gas
connections.
To avoid possibility of explosion or fire, never use a match or
open flame to test for leaks.
Check for leaks using an approved chloride-free soap and
water solution, an electronic combustible gas detector, or
other approved testing methods.
To prevent property damage or personal injury due to fire,
the following instructions must be performed regarding gas
connections, pressure testing, location of shutoff valve and
installation of gas piping.
NOTE: Never exceed specified pressures for test-
ing. Higher pressure may damage the gas valve and
cause subsequent overfiring, resulting in heat
exchanger failure.
Disconnect this unit and shutoff valve from the gas supply
piping system before pressure testing the supply piping sys-
tem with pressures in excess of 1/2 psig (3.48 kPa).
This unit must be isolated from the gas supply system by
closing its manual shutoff valve before pressure testing of
gas supply piping system with test pressures equal to or less
than 1/2 psig (3.48 kPa).
WARNING
CAUTION

Propane Gas Tanks and Piping

If the gas furnace is installed in a basement, an excavated
area or confined space, it is strongly recommended to
contact a propane supplier to install a gas detecting warning
device in case of a gas leak.
• Since propane gas is heavier than air, any leaking gas can
settle in any low areas or confined spaces.
• Propane gas odorant may fade, making the gas
undetectable except with a warning device.
A gas detecting warning system is the only reliable way to de-
tect a propane gas leak. Rust can reduce the level of odorant
in propane gas. Do not rely on your sense of smell. Contact
a local propane gas supplier about installing a gas detecting
warning system. If the presence of gas is suspected, follow
the instructions in the Safety Considerations section of this
manual.
All propane gas equipment must conform to the safety stan-
dards of the National Board of Fire Underwriters, NBFU
Manual 58.
For satisfactory operation, propane gas pressure must be
10 inch WC at the furnace manifold with all gas appli ances
in operation. Maintaining proper gas pressure depends on
three main factors:
1. Vaporization rate, depending on temperature of the
liquid, and "wetted surface" area of the con tainer or
containers.
2. Proper pressure regulation. (Two-stage regulation is
recommended for both cost and efficiency).
3. Pressure drop in lines between regulators, and be-
tween second stage regulator and the appliance. Pipe
size will depend on length of pipe run and total load of
all appliances.
Complete information regarding tank sizing for vaporiza tion,
recommended regulator settings, and pipe sizing is available
from most regulator manufacturers and propane gas suppliers.
Use a pipe thread compound that is approved for natural gas
and LP gas.

Ductwork

Never allow the products of combustion, including carbon
monoxide, to enter the return ductwork or circulation air
supply.
Duct systems and register sizes must be properly designed
for the CFM and external static pressure rat ing of the fur-
nace. Ductwork should be designed in accor dance with the
recommended methods of "Air Conditioning Contractors of
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WARNING
WARNING