Camus Hydronics DFH/W1100, Инструкция по установке, эксплуатации и обслуживанию

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24
Model
Voltage
Requirement
Maximum
Over Current
Protection
Full Load
Amps
[Amperes] [Amperes]
500 -
1200
460VAC, 60Hz, 3
Phase
10
0.9
1500 -
2000
1.4
2500 1.8
3000
2.1
3500 3.5
4000 -
5004
5.3
6004
6.8
The combustion air fan motor operates on 230 VAC, 3 phase,
60 Hz. This three phase voltage is generated by the variable
frequency drive (VFD) and supplied directly to the fan motor.
The appliance, when installed, must be electrically grounded in
accordance with the requirements of the authority having
jurisdiction or in the absence of such requirements, with the
latest edition of the National Electrical Code ANSI/NFPA No.
70. When the unit is installed in Canada, it must conform to the
Canadian Electrical Code, C22.1, Part 1 and/or local Electrical
Codes.
•
All wiring between the appliance and field installed devices
shall be made with wire having minimum 220ºF (105ºC)
rating.
•
Line voltage wire exterior to the appliance must be
enclosed in approved conduit or approved metal clad
cable.
•
The pump must run continuously when appliance is being
fired.
•
To avoid serious damage, DO NOT ENERGIZE the
appliance until the system is full of water. Ensure that all
air is removed from the pump housing and piping before
beginning initial operation. Serious damage may result if
the appliance is operated without proper flow.
•
Provide the appliance with proper overload protection.
5.2 VARIABLE FREQUENCY DRIVE (VFD)
This appliance uses a Variable Frequency Drive (VFD) which
provides power to the combustion fan. The fan motor operates
on 230VAC 3 phase power. This three phase voltage is
generated by the VFD and supplied directly to the fan motor.
The VFD receives a modulating signal (4-20 mA) from the local
modulating control or a remote source based on water
temperature to vary the frequency of the voltage supplied to
the fan motor from 20 Hz up to 60 Hz. This varies the output of
the combustion air fan from 20% up to 100% of capacity
corresponding to the same variation in burner input. The VFD
is driven towards 100% during the pre-purge portion of the
start-up sequence. Once control self checks are completed,
the VFD is provided with a signal to operate at soft start level
for initial burner ignition. After main burner ignition is
established, the modulating signal provided will use the VFD to
vary the fan speed based VFD to vary the fan speed based on
desired water temperature set point.
CAUTION
The voltage output from the variable frequency drive to the
combustion air fan is 230VAC, 3 Phase. AVOID contact
with high voltage wiring
5.3 DIFFRENTIAL AIR PRESSURE SWITCH
A normally open differential air pressure switch is used to
prove operation of the combustion air fan. The pressure
switch sensing points are installed at the fan outlet as the
air moves into the inlet of the burner. One point measures
total pressure (+air) and is connected to a pitot tube facing
the flow from the fan paddle wheel. The other point
measures static pressure. Differential pressure at the
switch will be affected by blockages at the fan inlet or at
the flue discharge. A minimum differential pressure across
the sensing points of the pressure switch proves operation
of the combustion air fan. This is set in the factory and
may be adjusted for field conditions. The diagnostics
display will exhibit a Status of no Air Flow when the
differential pressure switch detects a sustained low air
condition. This condition could be caused by a number of
factors including:
•
Sensing line broken or loose fitting.
•
Dirty filter or blocked vent.
•
Steady high wind condition exceeding 40 MPH.
•
Incorrectly set switch.
•
Missing bleed restrictor on total pressure side air line.
5.4 BLOCKED FLUE SWITCH
A normally closed block flue switch is used to shut down
the appliance under the following conditions:
1) Air intake 50% blocked
2) Vent outlet 80% blocked
5.5 HIGH and LOW GAS PRESSURE
SWITCHES (Optional)
A manual reset differential gas pressure switch is standard
on models 3000 – 5000 and available as an option on
models 500 - 2500. If differential gas pressure exceeds
the maximum setting of the pressure switch, the appliance
will shut down and an open gas pressure switch will be
shown on the display. A low gas pressure switch is
standard and monitors the minimum incoming gas supply
pressure supplied to the gas train. If gas pressure falls
below the minimum setting of the pressure switch, the
appliance will shut down and an open gas pressure switch
will be shown on the display.
5.6 HIGH LIMIT
A high limit aqua-stat control is located at the back of the
appliance and the control bulb is installed in a dry well in
the heat exchanger header outlet. The setting of this
control limits maximum discharge water temperature. A
manual reset high limit will have a red reset button which
must be pushed whenever water temperature has
exceeded the set point of the manual reset limit. The
temperature of the water in the heat exchanger must drop
a minimum of 15°F (8.3°C) below the setting of the high
limit control before the reset function can be activated.
Whenever an appliance is supplied with both an auto reset
and manual reset high limit always set the auto reset limit
10
ºF (5.5°C) below the manual reset limit. This will prevent
nuisance tripping of the manual reset.