Carrier 58PHA/PHX instruction manual Return Air Connections, GAS Piping Fire or Explosion Hazard

Return Air Connections

!WARNING

FIRE HAZARD

Failure to follow this warning could cause personal injury, death and/or property damage.

Never connect return-air ducts to the back of the furnace. Follow instructions below

Downflow Furnaces

The return-air duct must be connected to return-air opening (bottom inlet) as shown in Fig. 19. DO NOT cut into casing sides (left or right). Side opening is permitted for only upflow and most horizontal furnaces. (See Fig. 19.) Bypass humidifier connections should be made at ductwork or coil casing sides exterior to furnace.

Upflow and Horizontal Furnaces

The return-air duct must be connected to bottom, sides (left or right), or a combination of bottom and side(s) of main furnace casing as shown in Fig. 18 and 20. Bypass humidifier may be attached into unused return air side of the furnace casing. (See Fig. 18 and 20.)

Not all horizontal furnaces are approved for side return air connections. (See Fig. 20.)

GAS PIPING

!WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Never purge a gas line into a combustion chamber. Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically for the detection of leaks to check all connections.

!WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury,death, and/or property damage.

Use proper length of pipe to avoid stress on gas control manifold and a gas leak.

!CAUTION

FURNACE OVERHEAT HAZARD

Failure to follow this caution may result in property damage.

Connect gas pipe to gas valve using a backup wrench to avoid damaging gas controls and burner misalignment.

!WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

If local codes allow the use of a flexible gas appliance connector, always use a new listed connector. Do not use a connector which has previously served another gas appliance. Black iron pipe shall be installed at the furnace gas control valve and extend a minimum of 2 in.(51 mm) outside the furnace.

Gas piping must be installed in accordance with national and local codes. Refer to current edition of NFGC in the U.S., the CAN/CSA-B149.1-05 in Canada.

Installations must be made in accordance with all authorities having jurisdiction. If possible, the gas supply line should be a separate line running directly from meter to furnace.

NOTE: In the state of Massachusetts:

1.Gas supply connections MUST be performed by a licensed plumber or gas fitter.

2.When flexible connectors are used, the maximum length shall not exceed 36 inches (915 mm).

3.When lever handle type manual equipment shutoff valves are used, they shall be T-handle valves.

4.The use of copper tubing for gas piping is NOT approved by the state of Massachusetts.

Refer to Table 6 for recommended gas pipe sizing. Risers must be used to connect to furnace and to meter. Support all gas piping with appropriate straps, hangers, etc. Use a minimum of 1 hanger every 6 ft. (2 M). Joint compound (pipe dope) should be applied sparingly and only to male threads of joints. Pipe dope must be resistant to the action of propane gas.

An accessible manual equipment shutoff valve MUST be installed external to furnace casing and within 6 ft. (2 M) of furnace. A 1/8-in. (3 mm) NPT plugged tapping, accessible for test gauge connection, MUST be installed immediately upstream of gas supply connection to furnace and downstream of manual equipment shutoff valve.

NOTE: The furnace gas control valve inlet pressure tap connection is suitable to use as test gauge connection providing test pressure DOES NOT exceed maximum 0.5 psig (14-in. wc) stated on gas control valve. (See Fig. 52.)

Some installations require gas entry on right side of furnace (as viewed in upflow.) (See Fig. 21.)

Install a sediment trap in riser leading to furnace as shown in Fig

22.Connect a capped nipple into lower end of tee. Capped nipple should extend below level of furnace gas controls. Place a ground joint union between furnace gas control valve and exterior manual equipment gas shutoff valve. A 1/8-in. (3 mm) NPT plugged tapping, accessible for test gauge connection, MUST be installed immediately upstream of gas supply connection to furnace and downstream of manual equipment shutoff valve.

58PHA

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