Filter
Top Products
All installations and services must be performed by qualified service personnel.
26
M. Electrical
1. Wiring
:
The furnace must be grounded in accordance with local codes or in
the absence of local codes with the National Electrical Code,
ANSI/NFPA 70-2002, or latest edition.
All wiring shall be performed by a qualified electrician or service person. The
wiring must comply with local codes, the instructions in this manual, and in the
absence of codes with the National Electrical Code, ANSI/NFPA-70, or latest
edition.
Follow these guidelines to complete the wiring portion of the installations.
A separate power supply circuit with over current protection and a disconnect
switch must be provided. The minimum fuse or circuit breaker size is 15 amp.
All electrical components and junction boxes shall be installed in such that they
are protected from water.
All MHA1/MDA1 series furnaces are supplied with a switch box to be mounted
on the outside surface of the right or left side casing. A strain relief bushing is
provided for support of the supply wire harness. Make the 115 volt supply
connection in this junction box. A green screw is provided in order to connect
the power supply ground wire. A disconnect switch can be field mounted on the
2x4 box provided. If not, the disconnect switch must be located reasonably close
to and within sight of the furnace.
NOTICE: The hot surface igniter and operation of this furnace depends on
correct polarity. The hot leg of the supply circuit must be connected to the black
line lead and the common leg to the white line lead in the field mounted junction
box. The hot leg must be connected through the disconnect switch in all cases to
prevent the hazard of electrical shock when servicing.
2. Field Wiring and Replacing Wiring
Field wiring between the furnace and devices not attached to the furnace shall
conform to the temperature limitation for Type T wire [63°F (35°C) rise] when
installed with the manufacturers instructions. If any of the original factory
supplied furnace wiring is replaced, or a separate device other than the
thermostat is wired internal to the unit, 105°C temperature rated thermoplastic
insulated wire or equivalent wire must be used.