Camus Hydronics DRW1000, Installation And Service Manual

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PART 4 WATER CONNECTION
∗ Check all applicable local heating, plumbing and building
safety codes before proceeding.
∗ If the appliance is installed above radiation level it must be
provided with a low water cut-off device at the time of
appliance installation (available from factory). Some local
codes require the installation of a low water cut-off on all
systems.
∗
A pressure relief valve is supplied with each
Dynaforce®. The relief valve must be mounted in a
vertical position and piped to the floor in a manner
acceptable to the enforcing authority.
∗
Minimum water operating system pressure should not
drop below 30 PSIG.
∗
Be sure to provide unions and gate valves at inlet and outlet
to the appliance so that it can be easily isolated for service.
The provision of a flow setter valve at the appliance outlet
will facilitate setting of the proper flow at the desired
temperature rise at high fire. It is particularly important to
confirm proper temperature rise for domestic hot water
applications. Improper flows can lead to premature tube
failure from scaling and will not be covered by warranty.
∗
This appliance is a low mass design which provides for
instant heat transfer. Special attention to water flow rates
will ensure that temperature rise is not excessive. See
Table 8 and 9.
∗
To eliminate trapped air, install venting devices at high
points in the system as well as in the piping on the suction
of the pump and in the piping on the discharge of the
appliance.
∗
Use suitable pipe hangers or floor stands to support the
weight of all water and gas piping.
∗
Always pump toward the heat exchanger inlet. Never pump
away from the exchanger since this will result in a low-
pressure zone, which will allow localized boiling and result
in heat exchanger damage.
∗
Dynaforce® must be installed so that the gas ignition
system components are protected from water (dripping,
spraying, rain, etc.) during appliance operation and service
(circulator replacement, control replacement, etc.)
Figure 16: Typical Space Heating System
4.1 FREEZE PROTECTION
∗
Appliance installations are not recommended outdoors in
areas where danger of freezing exists unless precautions
are taken. Maintaining a mixture of 50% water and 50%
propylene glycol is the preferred method of freeze
protection in hydronic systems. This mixture will protect the
appliance to approximately -35ºF (-37ºC). To maintain the
same temperature rise across the appliance increase the
GPM flow by 15% and the head loss by 20%.
The following example demonstrates the procedure to follow for
calculating the revised head for the heat exchanger when using
a water / glycol mixture.
•
Given that Camus® is showing a heat exchanger flow
and head loss of 100 gpm @ 10 feet
•
Increasing the flow by 15% now results in a head loss of
13 feet at 115 gpm (from B&G system syzer). At this
increased flow Camus® now recommends to increase
the head loss by 20%.
•
The requirement for the heat exchanger with water /
glycol mixture will now be 115 gpm @ 15.6 feet. (ie. 1.2
x 13ft. = 15.6 ft.)
• A similar procedure must be followed to calculate the
additional head loss in pipe and fittings in order to
arrive at the proper pump selection.
∗
For outdoor installations in colder climates a snow screen
should be installed to prevent snow and ice accumulation
on and around the appliance. Regular inspections should
be made to ensure that air intake and vent are free of snow
and ice. Always consider the use of a shelter such as a
garden shed in lieu of direct exposure of the appliance to
the elements. The additional protection afforded by the
shelter will help to minimize nuisance problems with
electrical connections and will allow easier servicing of the
appliance under severe weather conditions.
4.2 WARNING REGARDING CHILLED WATER
AND HEATING COIL SYSTEMS
When an appliance is connected to a refrigeration system where
the same water is used for heating and cooling, the chiller must
be piped in parallel with the appliance. Appropriate flow control
valves; manual or motorized must be provided to prevent the
chilled water from entering the appliance.
The appliance piping system of a hot water boiler connected to
heating coils located in air handling units 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.
Figure 17: Chilled Water System
4.3 INLET AND OUTLET CONNECTIONS
• All water connections are groove-lock fittings.
• For ease of service, install unions on inlet and outlet of the
Supply
Return
System
Pump