GBT A2-035, Инструкция по установке и эксплуатации

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WATER CONNECTIONS
The type of system in which the boiler/heater is to be used will determine the type of water connections to be
made. Consult the piping schematics provided in the DIAGRAMS section before beginning the installation. Be
sure to install the unit in accordance with the installation instructions to insure proper operation and safety.
The heater/boiler should be located so that any water leaks will not cause damage to the adjacent area or
structures. If this cannot be avoided, use of a properly sized, drained catch pan is recommended. The catch
pan must not impair combustion air flow to the burner. Union connections and shut off valves must be provided
at the unit to facilitate future service which may be required.
The ASME pressure relief valve supplied on the unit must be piped to a drain or to a safe location to prevent
accidental burns should the valve discharge hot water. DO NOT install a valve between the relief valve and the
heater. DO NOT install reducing coupling, restriction, or valve in the relief valve discharge line. DO NOT pipe
to an area where freezing could occur. Local code requirements concerning size, type and placement of other
safety valves must be followed. The relief valve should be checked at least once yearly by manually operating
the release lever to insure proper operation.
A discharge line must be connected to the pressure relief valve and piped to a safe
location. Do Not Install a valve or other restriction between the relief valve and
heater, or the relief valve and the end of the discharge line. Water discharging from
the relief valve will be very hot and may cause series injury.
If the heater/boiler is connected to a water storage tank, a temperature and pressure relief valve must be
installed on the tank. The temperature/pressure relief valve serves as a safety device to prevent excessive
pressure and temperature. Excessive pressure may be caused by the expansion of water when it is heated in a
closed system. A closed system is one that has a check valve, back-flow-preventer, or a pressure-reducing
valve in the cold water supply line. In this type of system it is normal for the relief valve to relieve small
quantities of water from the closed system when the boiler is firing and no water is being used. An expansion
tank or other suitable means must be provided to control thermal expansion.
Insulating or dielectric unions or bushings should be used in connections between dissimilar metal fittings (such
as between copper and galvanized). These fittings are required to minimize electrolytic corrosion, which can
result from direct connection of dissimilar metals in a water system.
A flow switch must be installed and wired to prevent the unit from firing if there is an inadequate flow of water
through the boiler/heater. A flow switch on this unit meets CSD-1 safety requirements as a low water cut-off
device.
Note: A factory-wired flow switch is provided on all CSD-1 models. The flow switch should be set
so that the heater/boiler will not fire when the flow rate is less than that which will provide greater than a 80
o
F
(44
o
C) temperature rise through the heater/boiler.
When used for both potable water heating and space heating, all piping and components connected to the
system for space heating must also be suitable for use with potable water. Do not introduce toxic chemicals,
such as those used for boiler treatment, into the system. Any components previously used with non-potable
water must not be connected to the potable water system.
Flow Switch
deg F deg C A2-035 A2-050 A2-070 A2-097 A2-120 A2-140
80 44 7.0 10.0 14 19 24 28
70 39 8.0 11 16 22 28 32
60 33 9.4 13 19 26 32 37
50 28 11 16 22 31 39 45
40 22 14 20 28 39 48 56
30 17 19 27 37 52
20 11 28 40 56
A2000 Model
Flow Rate (gpm) Vs. Water Temperature Rise
Recommended Temperature Rise: 20 - 45
o
F
Temp Rise