MG2S Installation Manual

19
• All gas piping must be installed in compliance with
local codes and utility regulations. In the absence
of local codes the gas line installation must comply
with the latest edition of the Federal Manufactured
Home Constructions & Safety Standard (H.U.D.
Title 24, Part 3280.707[a][2]), National Fuel Gas
Code (ANSI Z223.1) or (CAN/CGA B149.1 or .2)
Installation Codes.
• Some local regulations require the installation of a
manual main shut-off valve and ground joint union
external to the furnace as shown in Figure 18. The
shut-off valve should be readily accessible for
service and/or emergency use. Consult the local
utility or gas supplier for additional requirements
regarding placement of the manual main gas shut-
off.
• Per ANSI 21.47, A 1/8-inch NPT plugged tapping,
accessible for test gauge connection, must be
installed immediately upstream of the gas supply
connection to the furnace external to the cabinet. If
local codes allow the use of a flexible gas appliance
connector, always use a new listed connector. Do
not use a connector that has previously serviced
another gas appliance.
• Gas piping must never run in or through air ducts,
chimneys, gas vents, or elevator shafts.
• Compounds used on threaded joints of gas piping
must be resistant to the actions of LP propane gas.
• The main gas valve and main power disconnect to
the furnace must be properly labeled by the installer
in case emergency shutdown is required.
• Flexible gas connectors are not recommended for
this type of furnace but may be used if allowed by
local jurisdiction. Only new flexible connectors
may be used. Do not use a connector which has
previously serviced another gas appliance.
• A drip leg should be installed in the vertical pipe
run to the unit if not entering the furnace through
the floor.
Shut-Off
Valve
Elbows
Gas Valve
Alternate Fuel
Line Entrance
M7TL BW Model Shown
GROUND
SENSOR
DHUM_IN
Y1_IN
H_OUT
L2-OUT
L2-IN
L1-IN
L1-OUT
Y1_OUT
Y/Y2_OUT
W_OUT
C
EXPANSION PORT
R
RED
GREEN
CONNECTION TO
FURNACE CONTROL
BOARD
MOTOR WIRING
HARNESS
RED
INPUT TERMINALS
COOL
HEAT
FAN SPEED
OUTPUT TERMINALS
STATUS LIGHTS
12 3
4
56 7
8
OFF ON
Figure 18. Typical Gas Connections
Table 10, (page 35) lists gas flow capacities for standard
pipe sizes as a function of length in typical applications
based on nominal pressure drop in the line.
The furnace is installed with a bottom gas entry. When
connecting the gas supply, provide clearance between the
gas supply line and the entry hole in the furnace casing
to avoid unwanted noise and/or damage to the furnace.
Typical gas hookups are shown in Figure 18.
Leak Check
WARNING:
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Never test for gas leaks with an open flame.
Use a commercially available soap solution
made specifically for the detection of leaks
to check all connections. A fire or explosion
may result causing property damage, personal
injury or loss of life.
AVERTISSEMENT :
RISQUE D’INDENDIE OU D’EXPLOSION
Le non-respect des avertissements de sécurité
pourrait entraîner des blessures graves, la mort ou
des dommages matériels.
Ne jamais utiliser une flamme nue pour vérifier la
présence de fuites de gaz. Pour la vérification de tous
les joints, utiliser plutôt une solution savonneuse
commerciale fabriquée spécifiquement pour la
détection des fuites de gaz. Un incendie ou une
explosion peut entraîner des dommages matériels,
des blessures ou la mort.
After the gas piping to the furnace is complete, all
connections must be tested for gas leaks. This includes
pipe connections at the main gas valve, emergency
shutoff valve and flexible gas connectors (if applicable).
The soap and water solution can be applied on each
joint or union using a small paintbrush. If any bubbling is
observed, the connection is not sealed adequately and
must be retightened. Repeat the tightening and soap
check process until bubbling ceases.
IMPORTANT NOTE
When pressure testing gas supply lines at pressures
greater than 1/2 psig (14 inch W.C.), the gas supply
piping system must be disconnected from the furnace
to prevent damage to the gas control valve. If the test
pressure is less than or equal to 1/2 psig (14 inch
W.C.), close the manual shut-off valve.