Maytag *TC, Installation Instructions Manual

22

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 fl exible 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

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. 
Please consult your local code authority. 

 WARNING:

The reduction of input rating necessary for high 
altitude installation may only be accomplished 
with factory supplied orifi ces. Do not attempt to 
drill out orifi ces in the fi eld. Improperly drilled 
orifi ces may cause fi re, explosion, carbon 
monoxide poisoning, personal injury or death.

The furnaces are shipped from the factory with orifi ces 
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, 12% at 3,000 feet, etc. This deration is in reference 
to the input rate and gas heating value at sea level.

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 fl amme nue por vérifi er la 
présence des fuites de gaz. Pour la vérifi cation 
de tous les joints, utiliser plutôt une solution 
savonneuse commerciale fabriquée spécifi quement 
pur la détection des fuites de gaz. Un incendie ou 
une explosion peut entraîner des dommages 
matériels, des blessures ou la mort.

 AVERTISSEMENT:

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, 

particularly in high altitude areas, the local gas utility 
usually specifi es the heating value at the residence’s 
gas meter as the “local value”.

For added fl exibility, two tables have been provided for 
natural gas installations with high or low heating values at 
sea level. Tables 15 and 16 (page 39) contain the orifi ce 
sizes and manifold pressure to use at various altitudes. 
Table 15 (HIGH) is for natural gas installations with a 
heating value of more than 1,000 Btu per cubic foot and 
Table 16 (LOW) is for less than 1,000 Btu per cubic foot. 
To determine which table to use:

1.  Consult your local utility for the local heating value at 

your installation.

2.  From Table 14 (page 38), fi nd 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 Table 15 

or if it’s LOW, use Table 16. See example.

Installation Example

Elevation:

 .................................................. 5,000 feet

Type of Gas:

 ........................................... Natural  Gas

Local Heating Value of Gas:

 .............................. 750

From Table 14, fi nd 750 and follow down the column, 
stop at the 5,000 feet row. The heating value listed is 
LOW. Table 16 will be used to determine orifi ce size and 
manifold pressure.

After changing the regulator pressure or changing the 
orifi ces, 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 & Adjusting the Input Rate section (page 28).

IMPORTANT NOTE: Observe the action of the burners 
to make sure there is no yellowing, lifting or fl ashback 
of the fl ame.