Single Wire Twinning - For Models With Twin Terminals - American Standard 50A65-475 Manual

Single Wire Twinning – For Models with Twin Terminals
Twinning Connection Diagram for Twinning One Stage Furnaces
with Single Wire Twinning Feature One Stage Heating Only Thermostat
FURNACE NO. 1
INTEGRATED FURNACE
CONTROL
TWIN Y W G
R
R1
ISOLATION
RELAY
(FIELD SUPPLIED)
SEE NOTE 4
W R G C/B
ONE STAGE
HEATING ONLY
THERMOSTAT
(WITH FAN SWITCH)
Twinning Connection Diagram for Twinning One Stage Furnaces
with Single Wire Twinning Feature One Stage Heating/One Stage Cooling Thermostat
FURNACE NO. 1
INTEGRATED FURNACE
CONTROL
TWIN Y W R G
R1
ISOLATION
RELAY
(FIELD SUPPLIED)
SEE NOTE 4
Y W G C/B
R
ONE STAGE
HEATING/COOLING
THERMOSTAT
INTEGRATED FURNACE
BLOWER OPERATION OF UNIT NO. 2
IS SYNCHRONIZED WITH UNIT NO. 1
VIA SIGNALS FROM "TWIN" CONNECTION
C
SEE NOTE 4
SEE NOTE 3
ALTERNATE WIRING CONFIGURATION
SEE NOTE 4
INTEGRATED FURNACE
BLOWER OPERATION OF UNIT NO. 2
IS SYNCHRONIZED WITH UNIT NO. 1
VIA SIGNALS FROM "TWIN" CONNECTION
C
SEE NOTE 4
SEE NOTE 3
RC
ISOLATION
RELAY
(FIELD SUPPLIED)
SEE NOTE 3
NOTES:
1. BOTH FURNACES MUST BE POWERED FROM THE SAME 115V. LEG
FURNACE NO. 2
2. INSURE 24V. FURNACE TRANSFORMERS ARE IN PHASE. PRIOR TO
CONTROL
3. CONNECTION MAY BE REQUIRED FOR ELECTRONIC THERMOSTAT.
TWIN Y W G C 4. IF CURRENT EXCEEDS THERMOSTAT CURRENT RATING, USE
R
ISOLATION
R1 RELAY
SEE NOTE 4
NOTES:
1. BOTH FURNACES MUST BE POWERED FROM THE SAME 115V. LEG
FURNACE NO. 2
2. INSURE 24V. FURNACE TRANSFORMERS ARE IN PHASE. PRIOR
CONTROL
3. IF OUTDOOR UNIT HAS A 24V. TRANSFORMER, AN ISOLATION
TWIN Y W R G C
4. IF CURRENT EXCEEDS THERMOSTAT CURRENT RATING, USE
5. CONNECTION MAY BE REQUIRED FOR ELECTRONIC THERMOSTATS.
ISOLATION
R1 RELAY
SEE NOTE 4
B
OUTDOOR UNIT
(NO TRANSFORMER)
Y
R
OUTDOOR UNIT
(WITH TRANSFORMER)
Y
ALTERNATE WIRING
CONFIGURATION
SEE NOTE 4
43
OF CIRCUIT PANEL.
COMPLETING CONNECTIONS, CHECK VOLTAGE BETWEEN "R"
TERMINALS OF EACH FURNACE. IF VOLTAGE IS GREATER THAN
10V., REVERSE THE "BL" AND "RD" SECONDARY LEADS ON ONE OF
THE FURNACE TRANSFORMERS.
ISOLATION RELAYS "RI" AS SHOWN. (DO NOT CONNECT "W"
TO "W.") ISOLATION RELAY NOT NEEDED IF THE THERMOSTAT
CONTACTS ARE RATED AT 1.OA. OR ABOVE.
Twinning requires that two
furnaces with the same configu-
ration, capacity and airflow
must be used. They shall have
common returns with equal
pressure drops or ducts with
equivalent lengths and sizes.
From Dwg. 21B341422 Rev. 1
OF CIRCUIT PANEL.
TO COMPLETING CONNECTIONS, CHECK VOLTAGE BETWEEN "R"
TERMINALS OF EACH FURNACE. IF VOLTAGE IS GREATER THAN
10V., REVERSE THE "BL" AND "RD" SECONDARY LEADS ON ONE OF
THE FURNACE TRANSFORMERS.
RELAY MUST BE INSTALLED. (FIELD SUPPLIED – USE PILOT DUTY
RELAY "RC", SUCH AS RLY0975.) SEE ALTERNATE CONNECTION.
ISOLATION RELAYS "RI" AS SHOWN. (DO NOT CONNECT "W"
TO "W.") ISOLATION RELAY NOT NEEDED IF THE THERMOSTAT
CONTACTS ARE RATED AT 1.OA. OR ABOVE.
From Dwg. 21B341423 Rev. 1