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Integral Indirect Gas-Fired Heat Module
OPTION
4.8 DEFINITIONS FOR GAS HEAT MODULE
Heater Type:
HM—indirect gas-fired duct furnace from
50 MBH up to 350 MBH
Input Capacity:
MBH—BTU per hour (÷1000) rating for
furnace input capacity.
Input capacities are 50, 75, 100, 125,
150, 200, 250, 300, and 350.
Fuel Type:
Natural Gas (Standard)—natural gas used
in most applications.
Propane (Option)—propane available.
Tube Material:
409 Stainless Steel (Standard)—provides
excellent corrosion resistance at elevated
temperatures and is more corrosion-
resistant than aluminized steel.
304 Stainless Steel (Option)—higher
chromium and nickel content than 409
stainless steel with superb corrosion
resistance at elevated temperatures.
Airflow Orientation:
Horizontal—module installed where
airflow in ductwork is horizontal through
the heater.
Thermal Efficiency:
80% Efficiency—standard thermal
efficiency for gas-fired heat module.
Thermal efficiency is ratio of output
capacity to input capacity.
Elevation:
0-2000 feet (Standard)—module burner
orifices for operation up to 2000 ft. above
sea level.
2001-6999 feet (Option)—module burner
orifices for operation 2001-6999 ft. above
sea level.
Above 7000 feet (Option)—module burner
orifices for operation over 7000 ft. above
sea level.
System/Inducer Voltage:
Single Phase—115V
Voltage Phase:
Single Phase only.
Control Voltage:
24 VAC (Standard)—secondary voltage
Control Type:
Modulating 5:1 Turndown (3:1 turndown
for propane)—module operates from
20-100% of output capacity based on
0-10Vdc input.
Modulating 10:1 Turndown—(6:1
turndown for propane) module operates
from 10% - 100% of output capacity
based on 0-10 VDC input.
Automatic Reset Fixed Temperature High
Limit Switch: (Standard)
Automatic reset limit switch included for
primary over-temperature protection.
Required by safety certifying agencies.
Combustion Air Pressure Switch:
(Standard)
Combustion air pressure switch included
to prove sufficient air flow is present.
Required by safety certifying agencies.
Manual Reset Flame Rollout Switch:
(Standard)
Manual reset flame rollout switch
included to monitor presence of burner
flame. Required by safety certifying
agencies.
Direct Spark Ignition Control (Standard):
Direct spark ignition control monitors Call
For Heat and ensures draft inducer fan is
operating before spark commences and
gas valve is energized for the ignition
period. Once burner ignites and cross
light and flame is detected, spark is
shut off. During heating operation, the
pressure switch and main burner flame is
constantly monitored for proper operation.
TECHNICAL DATA