Carrier 58DFA Installation, Start-Up, And Operating Instructions Manual Download

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Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.

The cabinet MUST have an uninterrupted or unbroken ground
according to National Electrical Code ANSI/NFPA 70-1993
and Canadian Electrical Code CSA C22.1 or local codes to
minimize personal injury if an electrical fault should occur.
This may consist of electrical wire or conduit approved for
electrical ground when installed in accordance with existing
electrical codes. Do not use gas piping as an electrical ground.

Make all electrical connections in accordance with the current
edition of the National Electrical Code ANSI/NFPA 70-1993 and
any local codes or ordinances that might apply. For Canadian
installations, all electrical connections must be made in accordance
with Canadian Electrical Code CSA C22.1 or authorities having
jurisdiction.

24-V WIRING — Make field 24-v connections at the 24-v termi-
nal strip. (See Fig. 9 and 10.) Connect terminal Y as shown for
proper operation in cooling mode. Use only AWG No. 18
color-coded wire.

The 24-v circuit contains an automotive-type, 3-amp fuse located
on the main control board. Any direct shorts during installation,
service, or maintenance could cause this fuse to blow. If fuse
replacement is required, use ONLY a 3-amp fuse of identical size.

ACCESSORY

Electronic air cleaner (EAC)

Two screw terminals (EAC-1 and EAC-2) are provided for
EAC connection. The terminals are energized with 115-v,
1-amp maximum during blower motor operation.

Step 7—Venting

Refer to the enclosed Installation Instructions, GAMA Venting
Tables for Category I Furnaces and QUIK•VENT™ Tables for
Category I Fan-Assisted Furnaces. The horizontal portion of the

venting system shall maintain a minimum of 1/4-in. upward slope
per linear ft and it shall be rigidly supported every 5 ft or less with
hangers or straps to ensure that there will be no movement after
installation.

Step 8—Start-up, Adjustment, and Safety Check

GENERAL — The furnace must have a 115-v power supply
properly connected and grounded. Thermostat wire connections at
R,W,C, and Y must be made at the 24-v terminal block on the
control board. The gas service pressure must not exceed 0.5 psig
(14-in. wc), but must be no less than 0.16 psig (4.5-in. wc).

Before operating the furnace, check each manual reset switch for
continuity. If necessary, press the button to reset the switch.

The blower compartment door must be in place to complete the
115-v circuit to the furnace.

This furnace is equipped with a fuse link in the gas control
area. The switch will open and shut off power to the gas valve
if a flame rollout or an overheating condition occurs in the gas
control area. DO NOT bypass the switch. Correct inadequate
combustion air supply problem and reset the switches.

SEQUENCE OF OPERATION — Using the schematic diagram,
follow the sequence of operation through the different modes. (See
Fig. 11.)

NOTE:

When the blower door is in place, 115v is supplied

through blower door switch ILK to heating fan relay HFR, and
transformer TRAN. Transformer TRAN energizes the safety
circuit containing auxiliary limit switch ALS, fuse link FL, and
limit switch LS to energize R.

With the furnace pilot lit, the thermocouple will energize the
thermal magnet circuit of gas valve GV, permitting gas flow to the
remaining portion of the gas valve.

Fig. 8—Typical Gas Pipe Arrangement

A89414

GAS

SUPPLY

MANUAL
SHUTOFF
VALVE

SEDIMENT
TRAP

UNION

Fig. 9—Control Center

A91226

MAX. 1.0 AMPS
115-VAC

SEC-2

SEC-1