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19
A190368
Fig. 27 -- 1--Speed Variable Furnace with Single--Speed Heat
Pump (Dual Fuel)
A190370
Fig. 28 -- 1--Speed Variable Furnace with Two--Speed Heat
Pump (Dual Fuel)
A190371
Fig. 29 -- Two--Stage Thermostat with 1--Speed Variable Fur-
nace and Two--Speed Air Conditioner
A190173
Fig. 30 -- Single--Stage Thermostat with 1--Speed Variable
Furnace and Two--Speed Air Conditioner
NOTES FOR FIGURES 25 -- 30
1. Heat pump MUST have a high pressure switch for dual fuel applications.
2. Refer to outdoor equipment Installation Instructions for additional information and setup procedure.
3. If the heat pump date code is 1501E or earlier, select the “ZONE” position on the two--speed heat pump control. Heat pumps having date codes 1601E and
later do not have or require a “ZONE” selection.
4. Outdoor Air Temperature Sensor must be attached in all dual fuel applications.
5. Dip switch No. 1 on Thermidistat should be set in OFF position for air conditioner installations. This is factory default.
6. Dip switch No. 1 on Thermidistat should be set in ON position for heat pump installations.
7. Dip switch No. 2 on Thermidistat should be set in OFF position for single--speed compressor operation. This is factory default.
8. Dip switch No. 2 on Thermidistat should be set in ON position for two--speed compressor operation.
9. Configuration Option No. 10 “Dual Fuel Selection” must be turned ON in all dual fuel applications.
10. NO connection should be made to the furnace HUM terminal when using a Thermidistat.
11. Optional connection: If wire is connected, ACRDJ jumper on furnace control should be removed to allow Thermidistat/Thermostat to control outdoor unit
staging.
12. Furnace must control its own stage heating operation via furnace control algorithm.
13. The RVS Sensing terminal “L” should not be connected. This is internally used to sense defrost operation.
14. DO NOT SELECT the “FURNACE INTERFACE” or “BALANCE POINT” option on the two--speed heat pump control board. This is controlled internally
by the Thermidistat/Dual Fuel Thermostat.
15. Dip switch D on Dual Fuel Thermostat should be set in OFF position for single--speed compressor operation. This is factory default.
16. Dip switch D on Dual Fuel Thermostat should be set in ON position for two--speed compressor operation.