Polaris BSS, Инструкция по эксплуатации, Страница: 17 / 63

17
INSTALLATION REQUIREMENTS
GAS SUPPLY SYSTEMS
Low pressure building gas supply systems are defined as those
systems that cannot under any circumstances exceed 14”
W.C. (1/2 PSI Gauge). These systems do not require pressure
regulation. Measurements should be taken to insure that gas
pressures are stable and fall within the requirements stated on
the water heater rating plate. Readings should be taken with
all gas burning equipment off (static pressure) and with all gas
burning equipment running at maximum rate (dynamic pressure).
The gas supply pressure must be stable within 1.5” W.C.
from static to dynamic pressure to provide good performance.
Pressure drops that exceed 1.5” W.C. may cause rough starting,
noisy combustion or nuisance outages. Increases or spikes in
static pressure during off cycles may cause failure to ignite or in
severe cases damage to water heater gas control valves. If your
low pressure system does NOT meet these requirements, the
installer is responsible for the corrections.
High pressure building supply systems use pressures that exceed
14” W.C. (1/2 PSI Gauge). These systems must use field supplied
regulators to lower the gas pressure to less than 14” W.C. (1/2
PSI Gauge). Water heaters require gas regulators that are properly
sized for the water heater input and deliver the rating plate specified
pressures. Gas supply systems where pressure exceeds 5 PSI
often require multiple regulators to achieve desired pressures.
Systems in excess of 5 PSI building pressure should be designed
by gas delivery professionals for best performance. Water heaters
connected to gas supply systems that exceed 14” W.C. (1/2 PSI
Gauge) at any time must be equipped with a gas supply regulator.
All models require a minimum gas supply pressure of 3.5”
W.C.(0.87 kPa) for natural gas and 8.0” W.C. (1.99 kPa) for
propane. The minimum supply pressure is measured while gas
is not flowing (static pressure) AND while gas is flowing (dynamic
pressure). The supply pressure (static and dynamic) should never
fall below 3.5” W.C.(0.87 kPa) for natural gas or 8.0” W.C. (1.99
kPa) for propane. The supply pressure should be measured with
all gas fired water heaters connected to the common main firing
at full capacity. If the supply pressure drops more than 1.5” W.C.
(0.37 kPa) as gas begins to flow to the water heater then the supply
gas system including the gas line and/or the gas regulator may
be restricted or undersized. See Supply Gas Regulator on page
17 and Supply Gas Line Installation on page 31. The gas control
valve on all models has a maximum gas supply pressure limit of
14” W.C.(3.48 kPa) The maximum supply pressure is measured
while gas is not flowing (static pressure) AND while gas is flowing
(dynamic pressure).
SUPPLY GAS REGULATOR
The maximum allowable gas supply pressure for this water heater
is 14 inches W.C. (3.5 kPa). Install a positive lock-up gas pressure
regulator in the gas supply line if inlet gas pressure can exceed 14
inches W.C. (3.5 kPa) at any time. Regulators must be sized/used
according to manufacturer’s specifications.
If a positive lock-up regulator is required follow these instructions:
1. Positive lock-up gas pressure regulators must be rated at or
above the input Btu/hr rating of the water heater they supply.
2. Supply gas regulators shall have inlet and outlet connections not
less than the minimum supply gas line size for the water heater
they supply
3. Positive lock-up gas pressure regulator(s) should be installed
no closer than 3 feet (1 meter) and no farther than 8 feet (2.4
meters) from the water heater’s inlet gas connection.
4. After installing the positive lock-up gas pressure regulator(s) an
initial nominal supply pressure setting of 7.0” W.C.(1.74 kPa) for
Natural Gas and 11.0” W.C. (2.74 kPa) for Propane (LP) while
the water heater is operating is recommended and will generally
provide good water heater operation. Some additional adjustment
may be required later to maintain a steady gas supply pressure.
5. When installing multiple water heaters in the same gas supply
system it is recommended that individual positive lock-up gas
pressure regulators be installed at each unit.
All gas piping must comply with local codes and ordinances or with
the current editions National Fuel Gas Code (ANSI Z223.1/ NFPA-
54) or the Natural Gas and Propane Installation Code (CAN/CSA
B149.1) whichever applies. Copper or brass tubing and fittings
(except tin lined copper tubing) shall not be used.
If the gas control valve is subjected to pressures exceeding 1/2 psi
(3.5 kPa), the damage to the gas control valve could result in a fire
or explosion from leaking gas.
If the main gas line Shut-off serving all gas water heaters is used,
also turn off the gas at each water heater. Leave all gas appliances
shut off until the water heater installation is complete.
A gas line of sufficient size must be run to the water heater. Consult
the current edition of National Fuel Gas Code (ANSI Z223.1/NFPA
54) or the Natural Gas and Propane Installation Code (CAN/CSA
B149.1) and your gas supplier concerning pipe size.
There must be:
•
A readily accessible manual shut off valve in the gas supply
line serving the water heater, and
• A sediment trap ahead of the gas control valve to help prevent
dirt and foreign materials from entering the gas control valve.
• A ground joint union of proper size between the manual shut
off valve and gas control valve to permit servicing of the unit.
Be sure to check all the gas piping for leaks before lighting the
water heater. Use a soapy water solution, not a match or open
flame. Rinse off soapy solution and wipe dry.
POWER SUPPLY
The water heaters covered in this manual require a 120 VAC,
1Ø (single phase), 60Hz, 7 amp power supply and must also be
electrically grounded in accordance with local codes or, in the
absence of local codes, with the National Electrical Code, ANSI/
NFPA 70 or the Canadian Electrical Code, CSA C22.1.
If any of the original wire as supplied with the water heater must
be replaced, it must be replaced with 105°C rated wiring or its
equivalent, except in the burner housing. In this case 200°C
rated wire must be used.
DEDICATED POWER WIRING AND BREAKERS
Dedicated power supply wires, ground wiring and dedicated
circuit breakers often prevent electrical line noise and
should be considered when installing the water heater.
POWER FLUCTUATIONS AND ELECTRICAL NOISE
The water heater’s control system requires a source of stable
clean electricity for proper operation. Connecting the water heater
to a branch circuit that is subject to fluctuations in voltage level or