Notes for Fig. 50A-H:

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. Select the ″ZONE″ position on the two-speed heat pump control.

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, dip switch No. 1 on furnace control should be set in ON position to allow Thermidistat/Thermostat to control furnace staging.

12. Optional connection. If wire is connected, ACRDJ jumper on furnace control should be removed to allow

Thermidistat/Thermostat to control outdoor unit staging.

13. Furnace must control its own high-stage heating operation via furnace control algorithm. This is factory default.

14. The RVS Sensing terminal ″L″ should not be connected. This is internally used to sense defrost operation.

15. 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.

16. Dip switch D on Dual Fuel Thermostat should be set in OFF position for single-speed compressor operation.

This is factory default.

17. Dip switch D on Dual Fuel Thermostat should be set in ON position for two-speed compressor operation.

BLWM at HI HEAT speed during the selected blower-OFF delay period before reverting to continuous-blower speed.

When the thermostat

″calls for low-cooling″, the blower motor

BLWM will switch to operate at low-cool speed (same speed as

LO HEAT). When the thermostat is satisfied, the blower motor

BLWM will operate an additional 90 seconds on low-cool speed before reverting back to continuous-blower speed.

When the thermostat ″calls for high-cooling″, the blower motor

BLWM will operate at COOL speed. When the thermostat is satisfied, the blower motor BLWM will operate an additional 90 seconds on COOL speed before reverting back to continuousblower speed.

When the R to G circuit is opened, the blower motor BLWM will continue operating for an additional 5 seconds, if no other function requires blower motor BLWM operation.

Continuous Blower Speed Selection from Thermostat -To select different continuous-blower speeds from the room thermostat, momentarily turn off the FAN switch or push-button on the room thermostat for 1-3 seconds after the blower motor BLWM is operating. The furnace control CPU will shift the continuousblower speed from the factory setting of LO HEAT to HI HEAT speed. Momentarily turning off the FAN switch again at the thermostat will shift the continuous-blower speed from HI HEAT to COOL. Repeating the procedure will shift the continuousblower speed from COOL to LO HEAT speed. The selection can be changed as many times as desired and is stored in the memory to be automatically used following a power interruption.

period, then shut off for 24 seconds then come back on at LO

HEAT speed. When the W/W1 input signal disappears, the furnace control begins a normal inducer post-purge period and the blower remains running at LO HEAT speed . If the R to W/W1-and-Y1and-G signals disappear at the same time, the blower motor

BLWM will remain on for the selected blower-OFF delay period.

If the R to W/W1-and-Y1 signals disappear, leaving the G signal, the blower motor BLWM will remain on for the selected blower-

OFF delay period then switch to continuous-blower speed.

When the R to W/W1-and-Y/Y2, R to W/W1-and-Y/Y2-and-G, R to W/W1-and-Y1-and-Y/Y2, or R to W-and-Y1-and-Y/Y2-and-G circuits are energized the furnace control CPU will switch to or turn on the blower motor BLWM at COOL speed, and begin a high-heat cycle. The blower motor BLWM will remain on until the end of the prepurge period, then shut off for 24 seconds then come back on at HI HEAT speed. When the W/W1 input signal disappears, the furnace control begins a normal inducer post-purge period and the blower switches to COOL speed after a 3 second delay. If the R to W/W1-and-Y/Y2-and-G or R to W/W1-and-Y1and-Y/Y2-and-G signals disappear at the same time, the blower motor BLWM will remain on for the selected blower-OFF delay period. If the R to W/W1-and-Y/Y2 or R to W/W1-and-Y1-and-

Y/Y2 signals disappear, leaving the G signal, the blower motor

BLWM will remain on for the selected blower-OFF delay period then switch to continuous-blower speed.

Step 3—Start-Up Procedures

PURGE GAS LINES

After all connections have been made, purge the gas lines and check for leaks.

HEAT PUMP

When installed with a heat pump, the furnace control automatically changes the timing sequence to avoid long blower off times during demand defrost cycles. When the R to W/W1-and-Y1 or R to

W/W1-and-Y1-and-G circuits are energized, the furnace control

CPU will switch to or turn on the blower motor BLWM at low cool speed (same speed as LO HEAT), and begin a low-heat cycle. The blower motor BLWM will remain on until the end of the prepurge

40

Table 10—Orifice Size and High/Low-Heat Manifold Pressure for Correct Input for Use With 060 Through 120 Size Furnaces Only

(Tabulated Data Based on 20,000/13,000 Btuh per Burner, Derated 2 Percent for Each 1000 ft Above Sea

Level)*

ALTITUDE

RANGE

(FT)

(FT)

(FT)

0 to

2000

0% derate

ALTITUDE

RANGE

Altitudes

2001 to

3000 or

Canada

Altitudes

2001 to

4500

5% derate

ALTITUDE

RANGE

3001 to

4000

7% derate

AVG GAS

HEAT VALUE

(BTU/CU FT)

850

875

900

925

950

975

1000

1025

1050

1075

1100

AVG GAS

HEAT VALUE

(BTU/CU FT)

775

800

825

850

875

900

925

950

975

1000

1025

AVG GAS

HEAT VALUE

(BTU/CU FT)

750

775

800

825

850

875

900

925

950

975

1000

Orifice no.

43

43

44

44

44

44

45

45

45

45

47

Orifice no.

43

43

44

44

44

44

45

45

45

47

47

Orifice no.

43

43

44

44

44

45

45

45

45

47

47

0.58

Manifold

Pressure

3.7/1.5

0.58

3.5/1.5

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.3

3.7/1.6

3.5/1.5

3.3/1.4

3.2/1.3

3.6/1.5

Manifold

Pressure

3.8/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.5

3.5/1.5

3.3/1.4

3.7/1.6

3.6/1.5

0.58

Manifold

Pressure

3.7/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.6/1.5

3.5/1.5

Orifice no.

43

43

43

44

44

44

45

45

45

45

47

44

44

44

45

45

Orifice no.

43

43

43

SPECIFIC GRAVITY OF NATURAL GAS

0.60

0.62

0.64

Manifold

Pressure

3.8/1.6

Orifice no.

42

Manifold

Pressure

3.2/1.4

Orifice no.

42

Manifold

Pressure

3.3/1.4

3.6/1.5

3.4/1.4

3.7/1.6

3.5/1.5

43

43

44

44

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

43

43

43

44

3.8/12.6

3.6/1.5

3.4/1.4

3.7/1.6

3.3/1.4

3.8/1.6

3.6/1.5

44

44

45

3.4/1.4

3.2/1.4

3.7/1.6

44

44

44

3.5/1.5

3.4/1.4

3.2/1.3

45

45

47

Orifice no.

42

43

43

44

44

44

45

45

45

3.4/1.5

3.3/1.4

45

45

3.7/1.6

45 3.2/1.4

45

SPECIFIC GRAVITY OF NATURAL GAS

0.60

Manifold

Pressure

3.2/1.4

3.7/1.5

3.4/1.5

Orifice no.

42

43

43

3.6/1.5

3.4/1.4

0.62

Manifold

Pressure

3.3/1.4

3.8/1.6

3.6/1.5

45

45

Orifice no.

42

42

43

3.7/1.6

3.5/1.5

3.4/1.4

0.64

Manifold

Pressure

3.4/1.4

3.2/1.4

3.7/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

44

44

44

44

45

45

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

43

44

44

44

45

45

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

45

47

3.2/1.4

3.7/1.6

45

45

3.4/1.4

3.2/1.3

45

45

SPECIFIC GRAVITY OF NATURAL GAS

0.60

0.62

0.64

Manifold

Pressure

Orifice no.

Manifold

Pressure

Orifice no.

3.5/1.5

3.3/1.4

Manifold

Pressure

3.8/1.6

3.6/1.5

3.4/1.4

3.6/1.5

42

43

43

44

3.3/1.4

3.7/1.6

3.5/1.5

3.8/1.6

42

43

43

43

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.2/1.3

3.6/1.5

44

44

45

45

45

45

45

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.5

3.3/1.4

3.7/1.6

44

44

44

45

45

45

45

3.7/1.5

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.4

* Orifice numbers shown in shading are factory installed.

NOTE: Percents of derate are based on midpoints of U.S. altitude ranges.

Orifice no.

42

42

43

43

44

44

44

44

45

45

45

0.66

Manifold

Pressure

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.5/1.5

44

44

44

45

45

45

Orifice no.

42

42

43

43

43

0.66

Manifold

Pressure

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

Orifice no.

42

42

43

43

44

44

44

44

45

45

45

0.66

Manifold

Pressure

3.5/1.5

3.2/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.7/1.5

3.5/1.5

3.3/1.4

41