A.O. Smith RESIDENTIAL GAS WATER HEATERS Installation And Operating Manual page 8

INSTALLATION GRAPHIC: GAS-FIRED POTABLE
WATER HEATING/SPACE HEATING SYSTEM
• If your water heater will be installed in the Commonwealth of Massachusetts, refer to the following
graphic during installation and during modifications to the water supply system.
TEMPERED WATER
TO FIXTURES
(MUST MEET TEMPS LISTED
IN MASS. CODE 248 CMR
MUST BE VERTICAL TO
REMOVE A IR BUBBLES
MIXING VALVE
(MUST BE INSTALLED BELOW
TOP OF WATER HEATER
AS PER MANUFACTURER'S
RECOMMENDATIONS)
WATER HEATER ACCEPTED
BY THE BOARD FOR
INSTALLATION IN
†
MASSACHUSETTS.
* MASSACHUSETTS INSTALLATION REQUIREMENTS:
1.) CONNECT ELECTRONICALLY-CONTROLLED TIMER TO AN ALL-BRONZE PUMP. PUMP MUST ACTIVATE EVERY 6 HOURS
FOR 60 SECONDS. TURN PUMP TIMER OFF BEFORE CLOSING PIPING LOOP SHUT-OFF VALVE.
2.) ALL WATER PIPING MUST BE INSTALLED AND INSULATED IN ACCORDANCE WITH MASSACHUSETTS CODE (248 CMR
& 780 CMR).
3.) PIPING LOOP BETWEEN WATER HEATER AND AIR HANDLER MUST BE INSTALLED IN COMPLIANCE WITH 248 CMR.
† REQUIRED FOR MASSACHUSETTS.
‡ PIPING FROM THE TOP OF THE WATER HEATER WITH TEES IS ACCEPTABLE.
8
TYPICAL MIXING VALVE INSTALLATION
COMBINATION SPACE HEATING / POTABLE WATER HEATING SYSTEM
CHECK
VALVE
†
)
UNION
HOT
WATER
OUT
EXPANSION TANK
VACUUM
RELIEF
†
VALVE
UNION
TEMP/
PRESSURE
RELIEF
VALVE
HANDLER
SEE
NOTE ‡
SHUT-OFF
VALVE
100'-0" MAXIMUM DISTANCE
FROM WATER HEATER TO FAN
COIL AND BACK. (DEVELOPED
LENGTH) NOT INCLUDING COIL
IN HEATING UNIT
www.hotwater.com
COLD WATER INLET
†
CHECK VALVE
(1/8" HOLE
DRILLED IN CLAPPER)
FLOW CONTROL
VA LV E
*
PUMP
OUT
COIL
TO
AIR
AIR
HANDLER
*
†
SHUT-OFF
VALVE
IN