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provided for EAC connection. (See Fig. 36.) These terminals
are energized with 115-v (1.0-amp maximum) during blower
motor operation.
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent
operation or performance satisfaction.
DO NOT connect furnace control HUM terminal to HUM
(humidifier) terminal on Thermidistat™, Zone Controller or
similar device. See Thermidistat™, Zone Controller, thermo-
stat, or controller manufacturer’s instructions for proper
connection.
2. Humidifier (HUM)
A quick-connect terminal (HUM) and screw terminal (C
OM
24V) are provided for 24-v humidifier connection. (See Fig.
36.) HUM terminal is energized with 24-v (0.5-amp maxi-
mum) when gas valve is energized.
NOTE:
A field-supplied, 115-v controlled relay connected to
EAC terminals may be added if humidifier operation is desired
during all blower operation.
Step 9—Removal of Existing Furnaces from Common
Vent Systems
When an existing Category I furnace is removed or replaced, the
original venting system may no longer be sized to properly vent
the remaining attached appliances. An improperly sized Category
I venting system could cause the formation of condensate in the
furnace and vent, leakage of condensate and combustion products,
spillage of combustion products into the living space, etc.
Step 10—Combustion Air and Vent Pipe Systems
GENERAL
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.
The 58MXB can be vented as either a direct vent (all sizes) or as
a non-direct vent (except for 140 size) application. A direct vent
system shall be installed in accordance with the direct vent
(2-pipe) procedures in the following Combustion Air and Vent
Pipe Systems section. For non-direct vent (1-pipe) applications,
refer to the non-direct vent (1-pipe) procedures in the same section.
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Fig. 34—Relocating J-Box
A05058
FACTORY
INSTALLED
LOCATION
ALTERNATE
FIELD
LOCATION
POWER ENTRY HOLE
FILLER PLUG (FACTORY-
SUPPLIED LOOSE PARTS BAG)
UNUSED 7/8-IN. DIAMETER
POWER ENTRY HOLES
UNUSED 7/8-IN. DIAMETER
POWER ENTRY HOLES
POWER ENTRY HOLE
FILLER PLUG (FACTORY-
SUPPLIED LOOSE PARTS BAG)
Table 7—Approved Combustion-Air and Vent Pipe, Fitting and Cement Materials
ASTM SPECIFICATION
(MARKED ON MATERIAL)
MATERIAL PIPE FITTINGS SOLVENT CEMENT AND PRIMERS
DESCRIPTION
D1527
ABS
Pipe
—
—
Schedule-40
D1785
PVC
Pipe
—
—
Schedule-40
D2235
For ABS
—
—
Solvent
Cement
For ABS
D2241
PVC
Pipe
—
—
SDR-21 & SDR-26
D2466
PVC
—
Fittings
—
Schedule-40
D2468
ABS
—
Fittings
—
Schedule-40
D2564
For PVC
—
—
Solvent
Cement
For PVC
D2661
ABS
Pipe
Fittings
—
DWV at Schedule-40 IPS sizes
D2665
PVC
Pipe
Fittings
—
DWV
F438
CPVC
—
Fittings
—
Schedule-40
F441
CPVC
Pipe
—
—
Schedule-40
F442
CPVC
Pipe
—
—
SDR
F493
For CPVC
—
—
Solvent
Cement
For CPVC
F628
ABS
Pipe
—
—
Cellular Core DWV at Schedule-40 IPS sizes
F656
For PVC
—
—
Primer
For PVC
F891
PVC
Pipe
—
—
Cellular Core Schedule-40 & DWV
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