WIRING – LOW VOLTAGE WIRING
230/208V, 1 phase and 3 phase equipment dual primary voltage transformers. All equipment leaves the factory wired on 240V tap. For 208V operation, reconnect from 240V to 208V tap. The acceptable operating voltage range for the 240 and 208V taps are:
TAP | RANGE | |
240 | 253 | - 216 |
208 | 220 | - 187 |
NOTE: The voltage should be measured at the field power connection point in the unit and while the unit is operating at full load (maximum amperage operating condition).
Nine (9) wires should be run from thermostat subbase to the 24V terminal board in the unit. A nine conductor, 18 gauge copper,
TABLE 3
THERMOSTAT WIRE SIZE
|
|
| Maximum |
Transformer |
|
| Distance |
VA | FLA | Wire Gauge | In Feet |
|
|
|
|
55 | 2.3 | 20 gauge | 45 |
|
| 18 gauge | 60 |
|
| 16 gauge | 100 |
|
| 14 gauge | 160 |
|
| 12 gauge | 250 |
|
|
|
|
COMPRESSOR CUTOFF THERMOSTAT AND OUTDOOR THERMOSTATS
Heat pump compressor operation at outdoor temperatures below 0° F are neither desirable not advantageous in terms of efficiency. Since most equipment at time of manufacture is not designated for any specific destination of the country and most of the equipment is installed in areas not approaching the lower outdoor temperature range, the compressor cutoffs are not factory installed.
Outdoor thermostats are available to hold off various banks of electric heat until needed as determined by outdoor temperature. The set point of either type of thermostat is variable with geographic region and sizing of the heating equipment to the structure. Utilization of the Heating Application Data and the heat loss calculation of the building are useful in determining the correct set points.
See Figure 8 for compressor cutoff and outdoor thermostat wiring.
FIGURE 8 – COMPRESSOR CUTOFF AND OUTDOOR THERMOSTAT WIRING
4 & 8 KW 1 Phase – 6 KW 3 Phase
Manual
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