E-Tech WH-35, Instruction Manual

Page: 12 / 48

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Table 2 on page 11 provides the MCA (Minimum Circuit
Ampacity) and MFS (Maximum Fuse Size). Use MCA to select
the minimum field wires size to power the unit and MFS to select
the maximum fuse size for over current protection as follows:
MCA = C x 1.25 + M + P
MFS = C x 2.25 + M + P
Where:
C - Compressor RLA
M - Blower Motor FLA
P - Pump FLA
MINIMUM CIRCUIT AMPACITY & MAXIMUM FUSE SIZE
Before removing any access panels or
servicing the water heater, make sure
the electrical supply to the water heater
is turned “OFF.”
Electrical Shock Hazard
•
Failure to do this could result in death,
serious bodily injury, or property
damage.
•
+The load current rating and the overcurrent protection for these conductors shall not exceed 15 amperes for 14 AWG. 20 amperes for 12 AWG and 30 amperes for
10 AWG copper; or 15 amperes for 12 AWG and 25 amperes for 10 AWG aluminum and copper-clad aluminum.
*For dry locations only. See 75°C column for wet locations.
MINIMUM WIRE SIZE
Allowable Ampacities of Insulated Conductors
Single-phase heat pump water heaters are two wire circuits. Three-phase heaters are three wire circuits. In addition to the foregoing,
a grounded conductor is required. Not more than three conductors in raceway, cable, or earth (directly buried), based on ambient
temperature of 30°C (86°F)
TABLE 3