Natco Fire Coil 85, Инструкция по установке и эксплуатации

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National Combustion Co., Inc.
Page 14
combustibles for hot water pipes.
Pipe the discharge of the relief valve (full size) to a
drain or in a manner to prevent injury in the event of
pressure relief. Install an air purger, an air vent, a
diaphragm-type expansion tank, and a hydronic flow
check in the system supply loop. Minimum fill pressure
must be 12psig (82.7kPa). Install shutoff valves where
required by code.
Suggested piping diagrams are shown (see Figures
6 through 14 ). These diagrams are meant only as a
guide. Components required by local codes must be
properly installed.
4A.2 Cold Water Make-Up — Boiler
1. Connect the cold water supply to the inlet
connection of an automatic fill valve.
2. Install a suitable back flow preventer between the
automatic fill valve and the cold water supply.
3. Install shut off valves where required.
NOTE: The boiler, when used in connection with a
refrigeration system, must be installed so the chilled
medium is piped in parallel with the boiler with
appropriate valves to prevent the chilled medium from
entering the boiler.
The boiler piping system of a hot water heating
boiler connected to heating coils located in air handling
appliances where they may be exposed to refrigerated
air circulation must be equipped with flow control
valves or other automatic means to prevent gravity
circulation of the boiler water during the cooling cycle.
A boiler installed above radiation level, or as
required by the authority having jurisdiction, must be
provided with a low water cutoff device either as a part
of the boiler or at the time of boiler installation.
4A.3 Water Flow Requirements — Boiler
A hydronic heating (closed loop) application re-
circulates the same fluid in the piping system. As a
result, no new minerals or oxygen is introduced into the
system. To ensure a proper operating temperature
leading to long boiler life, a flow rate has been
established based on the fluid temperature rise for this
specific size boiler.
Pump-mounted boilers can be ordered for use in
primary secondary piping systems. The pumps used are
sized for the headloss through the heater, plus 30 feet
(9.1m) of full-sized piping (same size as boiler outlet)
and a normal number of fittings.
Table 8 specifies water flow rates for boilers,
which will enable the user to size a pump. The headloss
shown is for the heater only, and the user will need to
add the headloss of the system piping to properly size
the pump.
The minimum inlet water temperature for the Fire
Coil 85 is 120°F (49°C) to avoid condensing on the
copper coils.
4A.4 Freeze Protection — Boiler
Boiler installations are not recommended in areas
where the danger of freezing exists unless proper
precautions are made for freeze protection. A non toxic,
heating system, anti-freeze may be added to the hydronic
system provided that the concentration does not exceed
50% and the anti freeze contains an anti foamant. When
a 50/50 mixture is used, increase the water flow
requirements by 15%, and increase the headloss
requirements by 20%.
Power outage, interruption of gas supply, failure of
system components, activation of safety devices, etc., may
prevent a boiler from firing. Any time a boiler is subjected
to freezing conditions, and the boiler is not able to fire, and/
or the water is not able to circulate, there is a risk of
freezing in the boiler or in the pipes in the system. When
water freezes, it expands. This can result in bursting of
pipes in the system, or damage to the boiler, which could
result in leaking or flooding conditions.
IMPORTANT NOTES: Different glycol products may
provide varying degrees of protection. Glycol products
must be maintained properly in a heating system, or they
may become ineffective. Consult the glycol specifications,
or the glycol manufacturer, for information about specific
products, maintenance of solutions, and set up according
to your particular conditions.
SECTION 4B.
Water Connections —
Water Heaters
4B.1 Water System Piping —
Water Heater
Hot water piping should be supported by suitable
hangers or floor stands. Do not support piping with this
appliance. Due to expansion and contraction of copper
pipe, consideration should be given to the type of
hangers used. Rigid hangers may transmit noise through
the system resulting from the piping sliding in the
hangers. It is recommended that padding be used when
rigid hangers are installed.
The Fire Coil 85 can be used with several different
types of readily available storage tanks. A pump draws
water from the storage tank and pumps the water through
the heater and back into the tank. Pump-mounted units have
a circulating pump built into the water heater. The pumps
used are sized for the headloss through the heater, plus 30
feet (9.1m) of full-sized piping (same size as boiler outlet)
and a normal number of fittings. Pumps used on pump-
mounted unit are sized for soft/normal or hard water, so
make sure a pump-mounted unit matches the water quality
of the installation.
Pipe the outlet from the heater’s relief valve such
that any discharge from the relief valve will be
conducted to a suitable place for disposal when relief
occurs. Do not reduce line size or install any valves in