5
CLOSED WATER SYSTEM
A closed system will exist if a back-flow preventer (check valve),
pressure reducing valve, or other similar device is installed in the
cold water line between the water heater and the street main (or
well). Excessive pressure may develop due to the thermal
expansion of heated water causing premature tank failure or
intermittent relief valve operation. This type of failure is not covered
by the limited warranty. An expansion tank may be necessary in
the cold water supply to alleviate this situation, see Fig. 1. Contact
the local plumbing authority.
If the temperature and pressure relief valve on the appliance
discharges periodically, this may be due to thermal expansion in
a closed water supply system. Contact the water supplier or local
plumbing inspector on how to correct the situation.
Do not plug
the temperature and pressure relief valve.
GAS CONNECTIONS
The minimum gas supply pressure is for input adjustment 4.5"
W.C for natural gas (11.0" W.C. for propane).
THE HEATER IS NOT INTENDED FOR OPERATION AT HIGHER
THAN 14.0 WATER COLUMN SUPPLY PRESSURE.
EXPOSURE TO HIGHER GAS SUPPLY PRESSURE MAY
CAUSE DAMAGE TO THE CONTROL WHICH COULD RESULT
IN FIRE OR EXPLOSION.
If overpressure has occurred such as
through improper testing of gas lines or emergency malfunction
of the supply system, the control must be checked for safe
operation. Make sure that the outside vents on the supply
regulators and the safety vent valves are protected against
blockage. These are parts of the gas supply system not the heater.
Vent blockage may occur during ice storms.
IT IS IMPORTANT TO GUARD AGAINST CONTROL FOULING
FROM CONTAMINANTS IN THE GAS WAYS. SUCH FOULING
MAY CAUSE IMPROPER OPERATION, FIRE OR EXPLOSION.
All piping must comply with local codes and ordinances or with
the National Fuel Gas Code (ANSI Z223.1 NFPA-54) whichever
applies. Copper and brass tubing and fittings (except tin lined
copper tubing) shall not be used.
REFER TO FIG. 1 FOR CONNECTION DETAILS. BEFORE
ATTACHING THE GAS LINE BE SURE THAT ALL GAS PIPE IS
CLEAN ON THE INSIDE.
TO TRAP ANY DIRT OR FOREIGN MATERIAL IN THE GAS
SUPPLY LINE, A DIRT LEG (SOMETIMES CALLED DRIP LEG)
MUST BE INCORPORATED IN THE PIPING, FIG. 1.
The dirt leg
must be readily accessible. Install in accordance with
recommendations of serving gas supplier. Refer to the latest
edition of ANSI Z223.1.
To prevent damage, care must be taken not to apply too much
torque when attaching gas supply pipe to gas valve inlet. The
valve inlet has a hexagon shape for use with a backup wrench.
Apply joint compounds (pipe dope) sparingly and only to the male
threads of pipe joints. Do not apply compound to the first two
threads. Use compounds resistant to the action of liquefied
petroleum gases. Do not use teflon tape on gas valve.
DISCONNECT THE APPLIANCE AND ITS INDIVIDUAL SHUT
OFF VALVE FROM THE GAS SUPPLY PIPING SYSTEM
DURING ANY SUPPLY PRESSURE TESTING EXCEEDING 1/2
PSI (3.5 kPa). GAS SUPPLY LINE MUST BE CAPPED WHEN
DISCONNECTED FROM THE HEATER. FOR TEST
PRESSURES AT 1/2 PSI (3.5 kPa) OR LESS, THE APPLIANCE
NEED NOT BE DISCONNECTED, BUT MUST BE ISOLATED
FROM THE SUPPLY PRESSURE TEST BY CLOSING THE MAIN
MANUAL GAS VALVE.
BEFORE PLACING THE HEATER IN OPERATION, CHECK FOR
GAS LEAKAGE. USE SOAP AND WATER SOLUTION OR
OTHER MATERIAL ACCEPTABLE FOR THIS PURPOSE. DO
NOT USE MATCHES, CANDLES, FLAME OR OTHER SOURCES
OF IGNITION TO LOCATE GAS LEAKS.
RELIEF VALVE (P)-FIG. 1
A NEW TEMPERATURE AND PRESSURE RELIEF VALVE
COMPLYING WITH THE STANDARD FOR RELIEF VALVES AND
AUTOMATIC GAS SHUT OFF DEVICES FOR HOT WATER
SUPPLY SYSTEMS, ANSI Z21.22 (LATEST EDITION) MUST BE
INSTALLED IN THE HEATER IN THE MARKED OPENING
PROVIDED. THE VALVE MUST BE OF A SIZE (INPUT RATING)
THAT WILL BE ADEQUATE FOR YOUR SIZE HEATER.
Check the metal tag on the relief valve and compare it to the
heater’s rating plate. The pressure rating of the relief valve must
not exceed the working pressure shown on the rating plate of the
heater. In addition, the hourly Btu rated temperature steam
discharge capacity of the relief valve shall not be less than the
input rating of the heater.
NO VALVE IS TO BE PLACED
BETWEEN THE RELIEF VALVE AND TANK. DO NOT PLUG
THE RELIEF VALVE.
The drain line connected to this valve must not contain a reducing
coupling or other restriction and must terminate near a suitable
drain to prevent water damage during valve operation. The
discharge line shall be installed in a manner to allow complete
drainage of both the valve and line.
DO NOT THREAD, PLUG
OR CAP THE END OF THE DRAIN LINE.
VENTING
WARNING
NEVER OPERATE THE HEATER UNLESS THE INTAKE AND
EXHAUST ARE VENTED TO THE OUTDOORS AND HAS
ADEQUATE AIR SUPPLY TO AVOID RISKS OF IMPROPER
OPERATION, FIRE, EXPLOSION, OR ASPHYXIATION.
WARNING
THE SEALED SHOT WATER HEATER IS CERTIFIED FOR
VERTICAL VENTING AND SIDE WALL VENTING. THE UNIT
CONSISTS OF AN INTAKE VENT TERMINAL AND AN EXHAUST
VENT TERMINAL WHICH MUST BE USED TO TERMINATE THE
VENTING ARRANGEMENT. IF THE VENT TERMINALS
SUPPLIED WITH THIS UNIT ARE NOT USED TO TERMINATE
THE VENTING ARRANGEMENT, THE RISK OF IMPROPER
OPERATION, FIRE, EXPLOSION, OR ASPHYXIATION WILL
INCREASE.
