TABLE 3
THERMOSTAT WIRE SIZE
|
|
| Maximum |
Transformer |
|
| Distance |
VA | FLA | Wire Gauge | In Feet |
|
| 20 gauge | 45 |
|
| 18 gauge | 60 |
55 | 2.3 | 16 gauge | 100 |
|
| 14 gauge | 160 |
|
| 12 gauge | 250 |
THERMOSTAT WIRING
COMPRESSOR CUTOFF THERMOSTAT AND OUTDOOR THERMOSTATS
Heat pump compressor operation at outdoor temperatures below 0° F are neither desirable nor 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.
HEAT ANTICIPATION
Both of the thermostats in Groups A and B below have a fixed heat anticipator for stage 1 with no adjustment required. Stage 2 has an adjustable anticipator for the W2 connection and fixed for the W3 connection. Both the W2 and W3 circuits are controlled by the stage 2 bulb. The only heat anticipator that needs to be checked is stage 2 and it should be set to match the load carried by the W2 circuit. The normal factory wiring provides for only on electric heat contactor to be controlled by W2, and the anticipator should be set at
.40A. If special field wiring is done, it is best to actually measure the load but a good role is .40A for each heat contactor controlled by W2.
FIGURE 8
COMPRESSOR CUTOFF AND OUTDOOR THERMOSTAT WIRING
4 - 10KW 1PH --- 6 & 9KW 3-PH
15 - 20KW
Manual
