Bryant 355M-40-5 Direct Venting, Removal of Existing Furnaces from Common Vent Systems, Ngpic

EAC1

EAC2

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Fig. 26ÐEAC Terminals on Control Center

(5.) Insert EAC stripped leads into control center EAC terminals by depressing terminal's arm with a screwdriver or finger. (See Fig. 26.)

(6.) Reinstall control box to furnace blower shelf using

2 screws removed earlier.

2. Humidifier (HUM)

Screw terminals (HUM and COM) are provided for 24-v humidifier connection. (See Fig. 24.) HUM terminal is energized with 24v (0.5-amp maximum) after inducer motor prepurge period.

NOTE: A field-supplied, 115-v controlled relay connected to EAC terminals may be added if humidifier operation is desired during blower operation.

3.Dehumidification (DH)

A 1/4-in. male quick-connect terminal is provided on control center to attach a normally open (N/O) humidistat contact when dehumidification is desired. (See Fig. 25.) Connect humidistat to thermostat R terminal and DH terminal on control center. A 15 percent reduction of cooling airflow or constant fan airflow will occur when DH terminal is energized and a single- or 2-speed "call for cooling" is received.

DIRECT VENTING

The 355MAV Furnaces require a dedicated (one 355MAV furnace only) direct-vent system. In a direct-vent system, all air for combustion is taken directly from outside atmosphere, and all flue products are discharged to outside atmosphere.

I.REMOVAL OF EXISTING FURNACES FROM COMMON VENT SYSTEMS

If furnace being replaced was connected to a common vent system with other appliances, the following steps shall be followed with each appliance connected to the venting system placed in opera- tion, while any other appliances connected to the venting system are not in operation:

1.Seal any unused openings in the venting system.

2.Inspect the venting system for proper size and horizontal pitch as required in the National Fuel Gas Code, ANSI Z223.1 or the CAN/CGA B149 Installation Codes and these instructions. Determine that there is no blockage or restric- tion, leakage, corrosion, and other deficiencies which could cause an unsafe condition.

3.If practical, close all building doors and windows and all doors between the space in which the appliance(s) con- nected to the venting system are located and other spaces of the building. Turn on clothes dryers and any appliance not

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connected to the venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they shall 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 shall operate continuously.

5.Test for draft hood equipped appliance spillage at the draft hood relief opening after 5 minutes of main burner opera- tion. Use the flame of a match or candle.

6.After it has been determined that each appliance connected to the venting system properly vents when tested as outlined above, return doors, windows, exhaust fans, fireplace damp- ers, and any other gas-burning appliance to their previous conditions of use.

7.If improper venting is observed during any of above tests, the venting system must be corrected.

Vent system or vent connectors may need to be resized. For any other appliances when resizing vent systems or vent connectors, system or connector must be sized to approach minimum size as determined using appropriate table found in the NFGC or NSC-

NGPIC.

II.COMBUSTION-AIR AND VENT PIPING

A.General

Combustion-air and vent pipe fittings must conform to American National Standards Institute (ANSI) standards and American Society for Testing and Materials (ASTM) standards D1785 (schedule-40 PVC), D2665 (PVC-DWV), D2241 (SDR-21 and SDR-26 PVC), D2661 (ABS-DWV), F628 (schedule-40 ABS), or F891 (PVC-DWV cellular core). Pipe cement and primer must conform to ASTM standards D2564 (PVC) or D2235 (ABS). See Table 6 for maximum pipe lengths and Fig. 31, 32, 33, 34, and 35 for exterior piping arrangements.

In Canada, construct all combustion-air and vent pipes for this unit of CSA or ULC certified schedule-40 PVC, PVC-DWV or ABS-DWV pipe and pipe cement. SDR pipe is NOT approved in Canada.

NOTE: Furnace combustion-air and vent pipe connections are sized for 2-in. pipe. Any pipe size change should be made outside furnace casing in vertical pipe. (See Fig. 27.) This allows proper drainage of vent condensate.

Combustion-air and vent pipes must terminate together in same atmosphere pressure zone, either through roof or sidewall (roof termination preferred), using accessory termination kit. See Table 5 for required clearances.

Furnace combustion-air and vent pipe connections must be at- tached as shown in Fig. 28. Combustion-air intake plug fitting and inducer housing alternate vent cap may need to be relocated in some applications.

CAUTION: When combustion-air pipe is installed above a suspended ceiling, pipe must be insulated with 3/8-in. thick Armaflex-type insulation. Combustion-air pipe should also be insulated when it passes through a warm, humid space.

CAUTION: When vent pipe is exposed to temperatures below freezing, such as when it passes through an unheated space or when a chimney is used as a raceway, pipe must be insulated as shown in Table 7 with Armaflex-type insulation.