State GS6 75 URRBS - Manual (Page 7)

7
CAUTION: IF BUILDING COLD WATER SUPPLY HAS A BACK-FLOW
PREVENTER, CHECK VALVE OR WATER METER WITH CHECK
VALVE, AN EXPANSION TANK MUST BE PROVIDED.
FIGURE 2.
CIRCULATING RETURN LINE CONNECTIONS
TEMPERED WATER LOOP, IF USED, CONNECT TO POINT "A".
STORED TEMPERATURE WATER LOOP, IF USED, CONNECT TO
COLD WATER INLET
WARNING
TEMPERATURE SETTING SHOULD NOT EXCEED SAFE
USE TEMPERATURE AT FIXTURES. SEE TEMPERATURE
REGULATION ON PAGE 11. IF HIGHER PREHEAT
TEMPERATURES ARE NECESSARY TO OBTAIN
ADEQUATE BOOSTER OUTPUT, ADD AN ANTI-SCALD
VALVE FOR HOT WATER SUPPLIED TO FIXTURES.
SINGLE TEMPERATURE
Where an exhaust fan is supplied in the same room with a heater,
suffi cient openings for air must be provided in the walls.
UNDERSIZED
OPENINGS WILL CAUSE AIR TO BE DRAWN INTO THE ROOM
THROUGH THE CHIMNEY, CAUSING POOR COMBUSTION.
SOOTING MAY RESULT IN SERIOUS DAMAGE TO THE HEATER
AND RISK OF FIRE OR EXPLOSION.
DO NOT OBSTRUCT THE FLOW OF COMBUSTION AND VENTILATING
AIR. ADEQUATE AIR FOR COMBUSTION AND VENTILATION MUST
BE PROVIDED FOR SAFE OPERATION.
UNCONFINED SPACE
In buildings of conventional frame, brick, or stone construction,
unconfi ned spaces may provide adequate air for combustion, ventilation
and draft hood dilution.
If the unconfi ned space is within a building of tight construction (buildings
using the following construction: weather stripping, heavy insulation,
caulking, vapor barrier, etc.), air for combustion, ventilation and draft hood
dilution must be obtained from outdoors. The installation instructions
for confi ned spaces in tightly constructed buildings must be followed to
ensure adequate air supply.
CONFINED SPACE
When drawing combustion and dilution air from inside a conventionally
constructed building to a confi ned space, such a space shall be provided
with two permanent openings, ONE IN OR WITHIN 12 INCHES (30.5cm)
OF THE ENCLOSURE TOP AND ONE IN OR WITHIN 12 INCHES
(30.5cm) OF THE ENCLOSURE BOTTOM. Each opening shall have a
free area of at least one square inch per 1000 Btuh (2,225mm
2 /Kw) of
the total input of all appliances in the enclosure, but not less than 100
square inches (645 square cm).
If the confi ned space is within a building of tight construction, air for
combustion, ventilation, and draft hood dilution must be obtained
from outdoors. When directly communicating with the outdoors or
communicating with the outdoors through vertical ducts, two permanent
openings, located in the above manner, shall be provided. Each opening
shall have a free area of not less than one square inch per 4000 Btuh
(8,900mm
2 /Kw) of the total input of all appliances in the enclosure. If
horizontal ducts are used, each opening shall have a free area of not
less than one square inch per 2000 Btuh (4,450mm
2 /Kw) of the total
input of all appliances in the enclosure.
VENTING
WARNING
THE INSTRUCTIONS IN THIS SECTION ON VENTING MUST BE
FOLLOWED TO AVOID CHOKED COMBUSTION OR RECIRCULATION
OF FLUE GASES. SUCH CONDITIONS CAUSE SOOTING OR RISKS
OF FIRE AND ASPHYXIATION.
This water heater must be protected from freezing downdrafts.
Remove all soot or other obstructions from the chimney that will retard
a free draft.
Type B venting is recommended with these water heaters.
This water heater must be vented in compliance with all local codes, the
current edition of the National Fuel Gas Code, ANSI Z223.1/NFPA 54,
and with the Category I Venting Table.
If any part of the vent system are exposed to ambient temperatures below
35 degrees F (2 degrees C) it must be insulated to prevent condensation.
• Do not connect the heater to a common vent or chimney with solid
MIXING VALVE APPLICATION FOR TWO TEMPERATURE WATER
VACUUM RELIEF
VALVE
*INSTALL PER
LOCAL CODES.