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After the gas piping to the furnace is complete, all
connections must be tested for gas leaks. This includes
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.
High Altitude Application
High altitude conversion with this furnace depends on
the installation altitude and the heating value of the gas.
The installation of this furnace at altitudes above 2,000
feet must meet the requirements of the National Fuel Gas
Code or local jurisdiction. In Canada, the requirements for
high altitude are different and governed by CGA B149.1.
Always consult your local code authority.
WARNING:
The reduction of input rating necessary for high
altitude installation may only be accomplished
with factory supplied orifices. Do not attempt to
drill out orifices in the field. Improperly drilled
orifices may cause fire, explosion, carbon
monoxide poisoning, personal injury or death.
This furnace is shipped from the factory with orifices and
gas regulator settings for natural gas operation at sea
level altitudes. At 2000 feet, the NFGC requires that this
appliance be derated 4% for each 1000 feet of altitude. For
example, the input needs to be reduced 8% at 2,000 feet,
RISQUE D’INDENDIE OU D’EXPLOSION
Le non-respect des avertissements de sécurité
pourrait d’entraîner des blessures graves, la
mort ou des dommages matériels.
Ne jamais utiliser une flamme nue por
vérifier la présence des fuites de gaz. Pour
la vérification de tous les joints, utiliser
plutôt une solution savonneuse commerciale
fabriquée spécifiquement pur la détection des
fuites de gaz. Un incendie ou une explosion
peut entraîner des dommages matériels, des
blessures ou la mort.
AVERTISSEMENT
:
Installation Example
Elevation:
................................................... 5,000 feet
Type of Gas:
............................................Natural Gas
Local Heating Value of Gas:
...............................750
Determine which natural gas table to use. From
, find 750 and follow down the column, stop at the
5,000 feet row. The heating value listed is LOW.
will be used to determine orifice size and manifold
pressure.
12% at 3,000 feet and etc. This deration is in reference to
the input rate and gas heating value at sea level.
To derate the furnace requires knowing the heating value of
the gas at the installation site. Heating values at particular
job sites vary for two reasons:
1. The chemical mixture of the gas varies from region to
region and is expressed as the “sea level heating value”.
2. The heating value varies by altitude. For this reason,
especially in high altitude areas, the local gas utility
specifies the heating value at the residence’s gas meter
as the “local value”.
For added flexibility, two tables have been provided for
natural gas installations with high or low heating values
at sea level.
contain the manifold pressure and orifice sizes to
gas installations with a heating value of more than 1,000
Btu per cubic foot and
1,000 Btu per cubic foot. To determine which table to use:
1. Consult the local utility for the local heating value at
your installation site.
2. From
, find your local heating
value as supplied by the utility company. Follow down
the column and stop at your altitude level.
3. If your sea level heating value is HIGH, use
or if it’s LOW, use
. See example.
After changing the regulator pressure or the orifices, it is
required that you measure the gas input rate. This may
be accomplished in the usual way, by clocking the gas
meter and using the local gas heating value. See Verifying
and Adjusting the Input Rate (
IMPORTANT NOTE:
Observe the action of the burners to make sure there
is no yellowing, lifting or flashback of the flame.
Summary of Contents for M4RC-072D-35C
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