Page is loading ...
FläktGroup DC_9072GB 20180323_R0 Specifications are subject to alteration without notice
PLATE HEAT EXCHANGER OF
COUNTERFLOW TYPE
INSTALLATION AND MAINTENANCE INSTRUCTIONS
EQRG PLATE HEAT EXCHANGER OF
COUNTERFLOW TYPE
The EQRG counter flow plate heat exchanger is delivered complete with
the Fläkt Woods developed sectional defrosting system. Down to -8°C
entering air no further action is required other than temperature control
input from main Air Handling Unit controls.
In cold climate lower than -8°C an additional input function is required of
the Air Handling Unit controller. See page 3 for further details.
Where the eQ unit is delivered complete with factory fitted controls, this
functionality is included.
Where controls are fitted on site by others, this control signal must be
provided by others.
The EQRG eQ plate
heat exchanger is equipped with a sloping drain tray
on the supply and exhaust air side for collecting the condensate.
The EQRZ-01 flushing water trough is available as an accessory for
collecting the water used for cleaning the supply air side of the heat
exchanger.
The drain tray and water trough have separate drain connections and
should be connected to a water trap. The drain connection has an
outside diameter of 32 mm.
The EQAZ-08 water trap is available as an accessory.
SECTION-BY-SECTION DEFROSTING
The heat exchanger is equipped with a by-pass damper and a combined
defrosting and shut-off damper unit, as well as actuator, control unit and
temperature sensor. The actuator for the by-pass damper is included.
Install as described in page 2.
The dampers are intended for heat transfer control and defrosting. During
the defrosting period, one damper section at a time closes for a time
depending on the outdoor temperature. In extreme cases two dampers
can be closed. The by-pass damper is closed. Since only a small part of
the heat exchanger is shut off, the supply air flow rate will be reduced by
not more than 5-10% during the actual defrosting period. During extreme
conditions the flow can descrease further. The magnitude of the flow
reduction is dependent on the fan type and the operating point of the fan.
EQAZ-08
BASIC DESIGN
Ensure that the damper blades are open during flushing
Exstract air
Outdoor air
Supply airExhaust air
2
Installation and maintenance instruction
FläktGroup DC_9072GB 20180323_R0 Specifications are subject to alteration without notice
Caution!
If a nozzle that delivers 2 l/min at 7 bar is used,
the pressure at the nozzle must not exceed
25 bar if the nozzle is used at an angle of
more than 20° to the face. The face area may
otherwise be deformed.
CONNECTION DIAGRAM FOR EQRG PLATE HEAT
EXCHANGER, EXCHANGER WITH SECTION-BY-
SECTION DEFROSTING
SERVICE INTERVALS
Inspection and possible cleaning should normally be carried out at
intervals of 6 months. This interval is based on an assumed operating
time of about 2000 hours over a 12-month period and a normal comfort
ventilation installation. If the dust content in the supply and/or exhaust air
is high, the unit should be inspected more frequently.
TO REMOVE DRY DUST
Vaccum or blow trough the heat exchanger with compressed air.
Check the inspection door gasket.
1
GND
24VAC
0-10VDC
Temp M4 M3 M2 M1
Power
2
5
1
2
5
1
2
5
1
2
5
1
2
5
3
1
2
4
5
6
By-pass damper ST4:1
N.B.: Reverse direction of travel
Section defrosting damper ST4:2
Integral control unit in the motor;
see instruction in the motor
cover
Section defrosting damper ST4:3
Section defrosting damper ST4:4
Section defrosting damper ST4:5
Temperature sensor
The external cable is connected to the bypass damper ST4:1.
The cables are connected at the factory.
TO REMOVE FATTY DUST
A. Apply cleaning agent to the face areas of the heat exchanger. A
suitable degreasing agent is ULCZ-01 which can be ordered from
your nearest sales office.
B. Wait for 10–15 minutes.
C. Flush with water.
D. Vacuum clean or blow clean with compressed air.
E. Check the inspection door gasket. Cleaning can also be carried out by
high-pressure spraying, and the nozzle should then be held 3 - 5 cm
from the face.After flushing, remove the water as above.
The EQRZ-01 flushing water trough is an accessory designed for
collecting flushing water on the supply air side.
3
Installation and maintenance instruction
FläktGroup DC_9072GB 20180323_R0 Specifications are subject to alteration without notice
temperature is between -8 and -22, the AHU controller must provide
the function described in the diagram below as well as the normal
temperature control function.
Note: The system is designed for use down to -22 °C.
At lower temperatures a pre-heater must be used.
Specification for the temperature control input signal to the EQRG
controller where the eQ unit is delivered without factory fitted standard
control:
The External temperature control signal (0-10 VDC) is connected to the
by-pass damper ST4:1. Where the design outdoor air
The line starts at -8 °C and 7, 5 VDC (Normal) or 7 VDC (Low) and has a slope -0,25 V/°C.
Note:
The signal must be limited to minimum 3, 5 VDC at low outdoor temperatures in order to prevent all air to pass the by-pass damper.
If problem occur with defrosting use the line “Low”. This gives less energy recovery in the heat exchanger.
TEMPERATURE CONTROL SIGNAL
Volt
10
9
8
7
6
5
4
3
2
1
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
-22
-24
-26
Signal - Temp.
Temp.
Normal
Low
Min 3,5 VDC
/
