ACCESSORY CONNECTIONS
The furnace control will allow
ELECTRONIC AIR CLEANER CONNECTION
Two 1/4” (0.64 cm) spade terminals (EAC and NEUTRAL) for electronic air cleaner connections are located on the control board. The terminals provide 115 VAC (1.0 amp maximum) during circulating blower opera- tion.
HUMIDIFIER CONNECTION
Two 1/4” (0.64 cm) spade terminals (HUM and NEUTRAL) for humidi- fier connections are located on the control board. The terminals provide 115 VAC (1.0 amp maximum) during heating system operation.
A mounting hole is provided on the control panel next to the furnace control board for mounting a humidifier transformer if required.
HUMIDISTAT CONNECTION
For better humidity control during cooling operation, an external humi- distat may be used. When using a external humidistat, put the HUMI- DISTAT jumper in the “YES” position. Connect the low voltage wiring as shown in Figures
SECTION VI: TWINNING AND STAGING
Twinning and staging is NOT allowed for modulating furnaces.
SECTION VII: VENT SYSTEM
VENT CONNECTIONS
Figure 26, "Combustion Air Inducer" shows the furnace as it is shipped from the factory. To convert to a horizontal or downflow position, remove the four screws that secure the inducer assembly and rotate 90° being careful not to damage the gasket. Reinstall screws. Remove cap from appropriate vent outlet location on the cabinet cut insulation in cabinet to same size as the hole provided and reinstall cap in the hole in the top panel.
In downflow applications, do not block the combustion air inlet. The furnace must be installed on a coil cabinet or subbase to allow com- bustionair to enter the burner compartment.
| COMBUSTION AIR INDUCER | |
90° | Mounting Screw | 90° |
| (Remove) |
|
Pressure Switch | Flue Transition | |
Tube Routing |
| (Do Not Remove) |
Pressure |
| |
Switch |
|
|
|
| Mounting Screw |
|
| (Remove) |
FIGURE 26: Combustion Air Inducer
CATEGORY 1 - 450 F. MAX. VENT TEMP.
The venting system must be installed in accordance with Section 5.3, Air for Combustion and Ventilation, of the National Fuel Gas Code Z223.1/NFPA 54 (latest edition), or Sections 7.2, 7.3 or 7.4 of CSA B149.1, National Gas and Propane Codes (latest edition) or applicable provisions of the local building code and these instructions.
The furnace shall be connected to a type B vent connector, and shall be connected to a type B vent only. The furnace shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel.
It is recommended that the appliance is installed in a location where the space temperature is 32 °F (0°C) or higher. If the appliance is installed in a location where the ambient temperature is below 32 °F (0°C), the combustion byproducts could condense causing damage to the appli- ance heat exchanger.
This appliance may be common vented with another gas appliance for residential installations as allowed by the codes and standards listed in these instructions.
VENTING
Category I venting consists of vertically venting one or more appliances in
VENTING INTO AN EXISTING CHIMNEY
This furnace may not be connected to any masonry chimney. However,
an existing masonry chimney may be used on as a chase through which the metal vent pipe passes.
FAN-ASSISTED COMBUSTION SYSTEM
This appliance is equipped with an integral mechanical means to draw products of combustion through the heat exchanger.
Ambient Combustion Air Supply
This type installation will draw the air required for combustion from within the space surrounding the appliance and from areas or rooms adjacent to the space surrounding the appliance. This may be from within the space in a
COMBUSTION
AIR
FIGURE 27: Combustion Airflow Path Through The Furnace Casing to the Burner Compartment
This type of installation requires that the supply air to the appli- ance(s) be of a sufficient amount to support all of the appliance(s) in the area. Operation of a mechanical exhaust, such as an exhaust fan, kitchen ventilation system, clothes dryer or fireplace may cre- ate conditions requiring special attention to avoid unsatisfactory operation of gas appliances. A venting problem or a lack of supply air will result in a hazardous condition, which can cause the appli- ance to soot and generate dangerous levels of CARBON MONOX- IDE, which can lead to serious injury, property damage and / or death.
18 | Johnson Controls Unitary Products |
