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912SD: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
28
A11157
Fig. 38 – Field-Supplied Isolation Relay for Humidifiers with Internal Power Supply
A190081
Fig. 39 – Thermostat Wiring Diagrams
NOTES FOR THERMOSTAT WIRING DIAGRAMS
1. Heat pump
MUST
have a high pressure switch for HYBRID
HEAT
r
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 with date
code 1601E and later do not have or require a “ZONE” selection.
4. Outdoor Air Temperature Sensor must be attached in all HYBRID
HEAT
r
dual fuel applications.
5. Configure the thermostat for air conditioner installations. Refer to
thermostat instructions.
6. Configure thermostat for heat pump installations. Refer to
thermostat instructions.
7. Configure thermostat for single-stage compressor operation. Refer
to thermostat instructions.
8. Configure thermostat for HYBRIDHEAT
r
dual fuel operation.
Refer to thermostat instructions.
9. NO connection should be made to the furnace HUM terminal when
using a thermostat with a 24 volt humidifier output.
10. The RVS Sensing terminal “L” should not be connected. This is
used internally to sense defrost operation.
11. If thermostat has internal control of heat pump balance point, DO
NOT SELECT the “FURNACE INTERFACE” or “BALANCE
POINT” option on the two-speed heat pump control board. Refer to
thermostat instructions.
12. Thermostat signals may vary. Consult thermostat installation
instructions for more information.
13.
VENTING
NOTE:
Planning for the venting system should be done in conjunction
with planning for the ductwork, drainage, and furnace accessories, such
as air cleaners and humidifiers. Begin assembling the venting system
AFTER
the furnace is set in place in the required orientation.
Venting for this furnace shall follow all Local codes for Category IV
venting systems. This furnace is CSA approved for venting with
PVC/ABS DWV venting systems. This furnace is also CSA approved
for venting with M&G DuraVent
R
PolyPro
R
or Centrotherm Innoflue
R
polypropylene venting systems using single wall straight and flex, and
required fittings (elbows, reducers, increasers, connectors, adapters)
only.
NOTE:
THESE INSTRUCTIONS
DO NOT
CONTAIN DETAILED
INSTALLATION INSTRUCTIONS FOR POLYPROPYLENE
VENTING SYSTEMS. Refer to the polypropylene venting system
24 V
Coil
To Humidifier Leads
To Com/24V Screw Terminal
on Thermostat Strip
To HUM Terminal On
Furnace Control Board
To Humidifier Leads
THERMOSTAT
THERMOSTAT
*
*
D
D
See notes 2, 5, 7, 9, and 12
See notes 1, 2, 4, 6, 7, 8, 9, 11, and 12
Single-Stage Furnace with Single-Speed Air Conditioner
Single-Stage Furnace with Single-Speed Heat Pump
NOTICE
!
OPTIONAL VENTING BELOW THE FURNACE
The venting system may be positioned below the furnace
ONLY
IF the
factory accessory External Vent Trap Kit is used. The External Vent
Trap Kit is only approved for PVC/ABS DWV venting systems.
CAREFULLY FOLLOW THE INSTRUCTIONS PROVIDED
WITH THE EXTERNAL VENT TRAP KIT FOR LAYING OUT
THE VENTING SYSTEM AND THE DRAIN SYSTEM.
The
instructions included with this furnace
DO NOT APPLY
to vent
systems that are located below the furnace.