Reznor ADFH Operation Manual - Manual (Page 15)

Form O-ADF/RDF, P/N 148385R2, Page 15
FIGURE 29 - Gas
Pressure Switches
Low Gas Pressure
Switch, P/N 204375
(automatic)
High Gas Pressure
Switch, P/N 204297
(manual reset)
3.7 Inlet Air
Controls
Description: The system is equipped with one of the 11 types of inlet air control
arrangements listed below. All systems provide a constant flow of outside air across
the burner at the required air volume (CFM). Refer to the wiring diagrams in the main
electrical box to determine which controls are on the system being serviced.

Option AR1 - a constant supply of 100% makeup air
 Option AR19 - 100% outside makeup air with variable supply air volume (CFM).
The discharge damper controlling the variable air supply is controlled by a manually
set remote potentiometer and can be varied from 100% to 20-25% of total rated airflow
(CFM). In response to changes in the discharge damper setting, the bypass damper
balances the volume of air so that the required fixed amount of air volume flows over
the burner.

Option AR20 - 100% outside makeup air with variable supply air volume (CFM).
The discharge damper controlling the variable air supply is automatically controlled
by a building pressure sensor and can be varied from 100% to 20-25% of total rated
airflow (CFM). In response to changes in the discharge damper setting, the bypass
damper balances the volume of air so that the required fixed amount of air volume
flows over the burner.

Option AR22 - a combination of outside makeup air and bypass return air includ-
ing modulating return air and bypass air dampers. The volume of outside air is regu-
lated by a remotely located, manually set potentiometer.

Option AR23 - a combination of outside makeup air and bypass return air includ-
ing modulating return air and bypass air dampers. The volume of outside air is regu-
lated automatically by a remotely located building pressure sensor.

Option AR33 - 100% outside makeup air with variable supply air volume (CFM).
The discharge damper controlling the variable air supply is automatically controlled by
a 0-10 VCD or 4-20 milliamp signal. In response to changes in the discharge damper
setting, the bypass damper balances the volume of air so that the required fixed
amount of air volume flows over the burner.

Option AR34 - a combination of outside makeup air and bypass return air includ-
ing modulating return air and bypass air dampers. The volume of outside air is regu-
lated by a 0-10 VCD or 4-20 milliamp signal.

Option AR36 - 100% outside makeup air with variable supply air volume (CFM).
The discharge damper controlling the variable air supply is automatically controlled
by a remotely located photohelic pressure sensor. In response to changes in the dis-
charge damper setting, the bypass damper balances the volume of air so that the
required fixed amount of air volume flows over the burner.

Option AR37 - a combination of outside makeup air and bypass return air includ-
ing modulating return air and bypass air dampers. The volume of outside air is regu-
lated by a remotely located photohelic pressure sensor.
WARNING: Burner
profile plates are
factory set to match
CFM requirements.
Do not adjust profile
plates without
contacting your
Sales Representative
for technical
assistance.
( NOTE: Both high and low gas pressure switches incorporate a vent limiting device
and do not require venting to the outdoors when used in an indoor installation.)
Airflow Dampers Function: Dampers operate in response to controls to provide the rated flow of makeup
air to the building. Minimum outside air is 20-25%.
Service: Clean all dampers of dust or dirt.
FIGURE 30 -
Damper
Motor
Function: The damper motor automatically actuates the return air, bypass, and/or
discharge dampers in response to an electrical control device. The damper motor is
direct-coupled to the dampers so there is no damper linkage to adjust.
Service: There is no service required on these motors other than external cleaning. If
the motors need replaced, replace with an identical damper motor.
Damper
Motor