Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 628

FDU-H
(d) When constructing drain piping for several units, position the common pipe about 100 mm below the drain outlet of each unit as
shown in the sketch. Use VP-30 (11/4˝) or thicker pipe this purpose.
(e) Be sure to provide heat insulation to hard PVC pipes of indoor placement.
(f) Do not ever provide an air vent.
(g) Avoid postitioning the drain piping outlet at a place where generation of odor may be stimulated. Do not lead the drain piping
direct into a sewer from where sulfur gas may generate.
If the duct is connected and then the blower is operated,
inside air pressure will become negative compared with
the atmospheric pressure.
Pressure head loss,
suction side
Duct
Air filter
Suction grill
Drain pipe
Drain pan
Example: If the pressure loss at the suction side, such as the suction
grill, air filter and duct, is 100 Pa (100 mm Aq), the level
of drain water will rise approx. 10 mm higher than the
state of operation stop.
(5) Drain Test
When the drain piping work is over, inject water to inspect if the piping is ar-
ranged properly or not.
Remove the side panel and supply gradually 1,000 cc of water to see if water
is drained smoothly or not. Check also for water leakage.
(6) Operating method of fan controller
This unit allows to continuously adjust the air volume with the fan controller switch which is built the electric equipment box.
It is not necessary to control the air volume (outside unit static pressure adjustment) with the damper, etc. at the duct side.
Select the point of operation so that it will be within the range of air volume withch can be operated. (Refer to the limitation of air
capacity as shown below.)
Location of the fan controller in the electric equipment box and the operating method are shown below.
Refer in advance to the blower characteristics quoted in the separate engineering data, and select the number on the scale of fan
controller switch.
Referring to the figure below, adjust the number on the scale of fan controller switch at the number selected during the test run
after completion of electrical work and check if the intended air volume is obtained or not.
This connector is provided for
emergency purpose and is used
when the fan controller becomes
out of order.
If this connector is connected to the
connector of the printed circuit
board, the unit can be operated with
100% capacity.
This connector is connected to the
printed circuit board.
15.5.2 Installation of remote controller
This is same as FDT(N) heat pump series, Refer to page 337.
15.5.3 Installation of outdoor unit
This is same as FDT(N) heat pump series, Refer to page 338.
15.6 MAINTENANCE DATA
This is same as FDT(N) heat pump series, Refer to page 348.
626
Duct
In running
Air outlet grille
In stopping
<Provision of trap>
Since the drain outlet is disposed at a position
that makes the pressure negative, it is neces-
sary to provide a trap (during the piping work)
in order to prevent water leakage due to rising
of water level in the drain pan.
Trap must be so constructed to facilitate clean-
ing. It should be better to employ a "T" joint
as shown below. In addition, the height of trap
should be as specified below. The trap should
be provided close to the unit.
Drain connection Provide a trap on way
Unit of the drain pipe as
shown at left.
H =100 mm or static pre-
1
ssure of blower
H =1/2 H
2
Turn this knob.
(Controlled within the range of scale 1 to 8 on the switch.)
or 50 ~ 100 mm
1