General Venting

Installer’s Guide

THIS FURNACE MUST BE VENTED TO THE OUT- DOORS.

THESE FURNACES ARE INDUCED DRAFT VENTED AND MUST NOT BE CONNECTED TO ANY VENT SERVING ANOTHER APPLIANCE. PLEASE NOTE THAT THESE FURNACES USE POSITIVE-PRES- SURE VENT SYSTEMS.

Proper venting is essential to obtain maximum effi- ciency from a condensing furnace. Proper installation of the vent system is necessary to assure drainage of the condensate and prevent deterioration of the vent system.

American Gas Association has certified the design of condensing furnaces for a minimum of 0" clearance from combustible materials with a single wall plastic vent pipe.

The recommended system is assembled from 2", 2-1/2", or 3" plastic pipe and fittings (See Table 7, page 12). Where the system is routed to the outdoors through an existing masonry chimney containing flue products from another gas appliance, or where required by local codes, then 3" venting of Type 29-4C stainless steel must be used in place of PVC material.

These furnaces have been classified as CATEGORY IV furnaces in accordance with the latest edition of ANSI Z21.47 • CAN/CGA-2.3 Standards. Category IV furnaces operate with positive vent pressure and with a vent gas temperature less than 140° F above the dewpoint. These conditions require special venting sys- tems, which must be gas tight and water tight.

NOTE:

When an existing furnace is removed from a venting system serving other gas appliances, the venting sys- tem is likely to be too large to properly vent the re- maining attached appliances.

The following steps shall be followed with each appli- ance remaining connected to the common venting sys- tem placed in operation, while the other appliances re- maining connected to the common venting system are not in operation.

1.Seal any unused openings in the common venting system.

2.Visually inspect the venting system for proper size and horizontal pitch and determine there is no blockage or restriction, leakage, corrosion or other deficiencies which could cause an unsafe condition.

3.Insofar as is practical, close all building doors and windows and all doors between the space in which the appliances remaining connected to the common venting system are located and other spaces of the building. Turn on clothes dryers and any appliances not connected to the common venting system. Turn on any exhaust fans, such as range hoods and bath- room exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan, close fireplace dampers.

4.Follow the lighting instructions. Place the appliance being inspected in operation. Adjust thermostat so appliance will operate continuously.

5.Test for spillage at the draft hood relief opening af- ter 5 minutes of main burner operation. Use the flame of a match or candle, or smoke from a ciga- rette, cigar, or pipe.

6.After it has been determined that each appliance re- maining connected to the common venting system properly vents when tested as outlined above, re- turn door, windows, exhaust fans, fireplace dampers and any other gas-burning appliance to their previ-

ous conditions of use.

If improper venting is observed during any of the above tests, the remaining common venting system must be corrected. Correction of the remaining common vent system should be done by referring to the latest edition of the National Fuel Gas Code (ANSI Z223.1) • CAN/ CGA B149.1 Installation Codes or “Exhibit J” of ANSI Z21.47 • CAN/CGA-2.3 Standards. The following are general steps to be used to correct or resize a re- maining vent system when a furnace which may not be common vented is removed from the system:

a. Determine the Btu per hour input of all remain- ing appliances attached to the venting system.

b. Determine the diameter, rise, and lateral of the existing venting system, as well as quantity and type of bends.

c. Use the appropriate tables in the latest edition of the National Fuel Gas Code (ANSI Z223.1 • CAN/CGA B149.1 Installation Codes or “Exhibit J” of ANSI Z21.47 • CAN/CGA-2.3 Standards. “Ex- hibit J” includes examples and drawings of typical venting systems.

IMPORTANT:

These furnaces may be installed as Direct Vent (sealed combustion) or as Nondirect vent (single pipe). The furnaces are shipped DIRECT VENT with sealed combustion.

For DIRECT VENT APPLICATION: The furnaces must be vented to the exterior of the house and combustion air MUST come through the inlet air pipe FROM OUTSIDE AIR.

For NONDIRECT VENT APPLICATION: The furnace shall be vented to the exterior of the house, but combustion air may enter from the surrounding area as long as combustion air requirements are met. (See AIR FOR COMBUSTION AND VENTILATION)

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