All installations and services must be performed by qualified service personnel.
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
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,
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.
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