A.O. Smith G9-T5040NVR, Installation Instructions And Use & Care Manual

Page: 13 / 36

Residen
al Standard Gas Water Heater Use and Care Guide • 13
GET
TING S
TAR
TED
Residen
al Standard Gas Water Heater Use and Care Guide • 13
GETTING STARTED
Space Hea ng
Some water heater models are equipped
with inlet/outlet connec ons for use with
space hea ng applica ons. If this water
heater is to be used to supply both space
hea ng and domes c potable (drinking)
water, the instruc ons listed below must
be followed.
• This water heater is suitable for
combina on water (potable) hea ng
and space hea ng and not suitable for
space hea ng applica ons only.
• Be sure to follow the manual(s)
shipped with the air handler system.
• This water heater is not to be used as
a replacement for an exis ng boiler
installa on.
• Do not use with piping that has been
treated with chromates, boiler seal or
other chemicals and do not add any
chemicals to the water heater piping.
• If the space hea
ng system requires
water temperatures in excess of 120°F,
install a Thermosta
c Mixing Valve
in the domes c (potable) hot water
supply at each point-of-use to limit the
risk of scald injury. Install the mixing
valve per its manufacturer’s instruc-
ons.
• Pumps, valves, piping, and fi
ngs
must be compa ble with potable
water.
• A properly installed fl
ow control valve
is required to prevent thermosiphon-
ing. Thermosiphoning is the result of a
con nuous
fl
ow of water through the
air handler circuit during the o
ff
cycle.
• The domes
c hot water line from the
water heater should be ver cal past
any mixing valve or supply line to the
air handler to remove air bubbles from
the system. Otherwise, these bubbles
will be trapped in the air handler heat
exchanger coil, reducing e
ffi
ciency.
• Do not connect the water heater to
any system or components previously
used with non-potable water heat-
ing appliances when used to supply
potable water.
Solar Installa on
If this water heater is used as a solar stor-
age heater or as a backup for the solar
system, the water supply temperatures
to the water heater tank may be in excess
of 120°F. A Thermosta
c Mixing Valve or
other temperature limi ng valve must be
installed in the water supply line to limit
the supply temperature to 120°F. The unit
must be set to Standard Mode (See Operat-
ing Modes in Opera on sec on on page
24).
NOTICE:
Solar water hea
ng systems can
o en supply water with temperatures
exceeding 180°F and may result in water
heater malfunc on.
Figure 11 - Combustion Space Heating and Potable Water (Typical Installation)
IN
REMOVE A
MUST BE VERTICAL TO
IR BUBBLES
E
OUT
COIL
AIR
HANDLER
TO
AIR
HANDLER
SHUT-OFF
VALVE
*
EXPANSION TANK
VACUUM
RELIEF
VALVE
COLD WATER INLET
VA
FLOW CONTROL
LV
PUMP
*
SHUT-OFF CHECK VALVE
†
(1/8” HOLE
DRILLED IN CLAPPER)
VALVE
CHECK
VALVE
†
TEMP/
PRESSURE
RELIEF
VALVE
TEMPERED WATER
TO FIXTURES
(MUST MEET TEMPS LISTED
IN MASS. CODE 248 CMR
†
)
MIXING VALVE
(MUST BE INSTALLED BELOW
TOP OF WATER HEATER
AS PER MANUFACTURER’S
RECOMMENDATIONS)
UNION UNION
HOT
WATER
OUT
*
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.
WATER HEATER ACCEPTED
BY THE BOARD FOR
INSTALLATION IN
MASSACHUSETTS.
†
TYPICAL MIXING VALVE INSTALLATION
COMBINATION SPACE HEATING / POTABLE WATER HEATING SYSTEM
SEE
NOTE ‡
100’-0” MAXIMUM DISTANCE
FROM WATER HEATER
TO FAN COIL AND BACK
(DEVELOPED LENGTH) NOT
INCLUDING COIL IN HEATING UNIT.
†