Camus Hydronics DRW1000, Инструкция по установке и обслуживанию

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Figure 19: Low Water Cut Off Electrical Connections (Watts)
Figure 20: Low Water Cut Off Electrical Connections (ITT)
4.10 RELIEF VALVE
This appliance is supplied with a relief valve sized in accordance
with ASME Boiler and Pressure Vessel Code, Section IV
(“Heating Boilers”). The relief valve is installed or shipped loose
and is installed in the vertical position and mounted in the hot
water outlet. No valve is to be placed between the relief valve,
and the appliance. To prevent water damage, the discharge
from the relief valve shall be piped to a suitable floor drain for
disposal when relief occurs. No reducing couplings or other
restrictions shall be installed in the discharge line. The discharge
line shall allow complete drainage of the valve and line. Relief
valves should be manually operated at least once a year. If a
relief valve discharges periodically, this may be due to thermal
expansion in a closed water supply system. Contact the water
supplier or local plumbing inspector on how to correct this
situation. Do not plug the relief valve.
CAUTION
Avoid contact with hot discharge water
4.11 CIRCULATING PUMP SELECTION
The appliance has a low mass stainless steel finned tube heat
exchanger for fast response and high heat absorption. Selecting
the proper pump will ensure that temperature rise does not
exceed the maximum recommended for the application and that
the heat exchanger tubes are not prematurely scaled or eroded.
4.11.1 CIRCULATING PUMP OPERATION OF HEAT
EXCHANGER
MOST IMPORTANT
This appliance is designed for continuous pump operation
when the burner is firing. The pump control option allows the
appliance circulating pump to be cycled “ON” prior to the
burner firing and cycled “OFF” some time after the set point
is satisfied.
The operation of the circulating pump is controlled by the
Dynaforce® temperature control (SOLA). When the appliance is
activated by a remote operating signal the pump will start and
run for the operating cycle and for a post purge period based on
temperature difference between inlet and outlet connections to
the appliance. The SOLA can directly operate pumps up to 1/6
HP. Larger pumps will require a separate relay or contactor.
To select the proper pump, it is strongly recommended to
consider the following:
•
Need to know the required flow (GPM) and pressure drop
for your appliance (see Table 8 and 9)
•
Type of application: hydronic heating or domestic hot water
(DHW).
•
For hydronic heating and DHW applications with normal
water hardness choose a pump which will result in a
temperature rise across the main heat exchanger according
to Tables 8 and 9, depending on the size of the heater. If
necessary, use a flow setter valve to achieve the desired
temperature rise.
•
For DHW applications with other than normal water
hardness choose a pump for the local water hardness
conditions. Alternatively run the pump continuously and
soften the water to normal levels. Damage to the heat
exchanger as a result of scaling or corrosive water
conditions is non-warrantable.
NOTE
The use of a system sensor is required in lead lag operation.
1) When variable speed main circulators ARE NOT used the
system sensor is to be placed into the return system piping.
2) When variable speed main circulators are used the system
sensor is to be placed into the supply system piping.
4.12 ∆ T HEAT EXCHANGER ALGORITHM
The Dynaforce® is constantly monitoring the inlet and outlet
water temperatures on the Dynaforce®, when the ∆T
approaches 40 o F the burner will modulate down, and when this
temperature is exceeded the gas valve will de-energize to
prevent overheating the heat exchanger.
Connection detail for placing
L.W.C.O in 24V circuit
WARNING: Be sure to remove the
jumper between H and P1
Pressure Switch
From
Flow
Switch
To High Limit