Catalogue

64 UH-PRC002-EN
Mechanical Specifications
through a side panel access plate. The high limit switch is accessible through a side panel access.
Duct discharge flanges for simple ductwork connection are provided.
Heat Exchanger
Standard heat exchanger construction consists of seam welded 20-gauge aluminized steel tubes
and 18-gauge aluminized steel headers.
Burners
Burners are die-formed, corrosion resistant aluminized steel, with stainless steel port protectors.
Port protectors prevent foreign matter from obstructing the burner ports. Burners individually
removable for ease of inspection and servicing. Each burner is provided with an individually
adjustable, manually rotated air shutter adjustment. Air shutter adjustment is fixed when side
access burner drawer is supplied.
Controls
A factory installed junction box is provided for all power connections. Standards units are provided
with a 24-volt combination single-stage redundant gas valve, consisting of a combination pilot
solenoid valve, automatic electric gas valve, pilot filter, pressure regulator, pilot adjustment and
manual shutoff. A flue vent fan relay and combustion air proving switch is also provided as
standard. Standard equipment includes spark-ignited intermittent pilot system with electronic
flame supervision. A 24V control transformer and a high limit are provided.
Flue Vent Fan
Flue vent fan is factory assembled to a sealed flue collection chamber and provides power venting.
The flue vent fan is activated in response to a low voltage (24V) single-stage thermostat. A
combustion air pressure switch is provided as standard to verify proper powered vent flow prior
to allowing the gas valve to operate.
Control Options
Two-Stage Gas Valve
Provides two stages of heat. Ignition is at low fire (50 percent of the furnace’s rated input). Requires
the use of a two-stage thermostat. (Thermostat not included.)
Electronic Modulating Gas Valve (Natural Gas Units Only)
Provides modulated heat output. Ignition is at full fire (100 percent input), and modulates the gas
input from 100 percent to 50 percent rated input. Available for use with room thermostat or duct
thermostat with remote setpoint adjustment. Duct thermostat available with optional override
room thermostat which causes the unit to go to full fire when the room temperature falls below the
override room thermostat.
Electronic Modulating 4–20 mA/0–10 Vdc Input
Provides modulated heat output. Ignition is at full fire (100 percent input), and modulates the gas
input from 100 percent to 40 percent rated input. The modulating gas valve shall operate in
response to a 4–20 mA or a 0–10 Vdc input from an external DDC control.
Heat Exchanger Options
Type 409 Stainless Steel
Heat exchanger tubes and headers are seam welded 20-gauge Type 409 stainless steel
Type 321 Stainless Steel
Heat exchanger tubes and headers are seam welded 20-gauge Type 321 stainless steel