Mitsubishi Heavy Industries SRF25ZMXA-S, Technical Manual & Parts List, Page: 43 / 126

- -
'14 • SRF-T-163
<T
able of pipe size restrictions>
◎
: Standard pipe size
○
: Usable
△
: Restricted to shorter pipe length limits
Additional charge volume (kg) = {Main pipe length (m)
-
Length covered without additional
charge shown in the table (m)} X Additional charge volume per meter of pipe shown in the table (kg/m)
Liquid pipe
Gas pipe
Usability
Maximum one-way pipe length
Length covered without additional charge
Usability
Maximum one-way pipe length
Length covered without additional charge
Usability
Maximum one-way pipe length
Length covered without additional charge
Pipe size
40 50 60
Additional charge volume per meter of pip
e
0.02kg/m
ø6.35 ø12.7
◎
30 15
◎
30 15
◎
30 15
0.06kg/m
ø9.52 ø12.7
△
10
5
△
10 15
△
10
5
Formula to calculate additional charge volume
NO
Are the existing units our products?
NO NO
NO NO NO NO
Is the existing pipe system to reuse free of corrosion, flaws or dents?
Repair the damaged parts.
Remove those branches.
Repair the damaged parts.
Check the pipe system for air tightness on the site.
Repair the damaged parts.
No loose pipe supports
NO
YES
ST
AR
T
The existing pipe system is reusable.
The existing pipe system is not reusable. Install a new pipe system.
YES
YES
YES
YES YES
Are an outdoor unit and an indoor unit connected to the existing pipe system to reuse?
Is the unit to install in the existing pipe system a twin-triple-double-twin model?
Is the existing pipe system to reuse free of gas leaks? (Check whether refrigerant charge was required frequently for the system before) Are heat insulation materials of the existing pipe system to reuse free of peel-offs or deterioration? (Heat insulation is necessa
ry for both gas and liquid pipes)
Change the branching pipe to a specified type.
Does the existing pipe system to reuse satisfy all of the following? (1) The pipe length is 30m or less. (2) The pipe size conforms to the table of pipe size restrictions. (3) The elevation difference between the indoor and outdoor units
conforms to the following restrictions.
Where the outdoor unit is above: 15m or less Where the outdoor unit is below: 15m or less
Which of the following refrigeration oils does the existing unit use? Suniso, MS, Barrel Freeze, HAB, Freol, ether oil, ester oil
Please make an inqui
ry for
reusability.
Change
Change is impossible.
Can Use
Can not Use
Repair is impossible. Air tightness is impossible. Remove is impossible Repair is impossible.
Repair Repair Repair
Some loose pipe supports
Air tightness is OK Remove
Check whether an existing pipe system is reusable or not by using the following flow chart.
Are not there any loose pipe supports?
Are there any branch pipes with no indoor unit connected?
NO
•
Please consult with our distributor in the area, if you need to recover refrigerant and charge it again.
•
Any combinations of pipe sizes not listed in the table are not usable.
※
If you obtain a negative figure as a result of calculation, no additional refrigerant needs to be charged.
Example)
When an 60 is installed in a 10m long existing pipe system (liquid
ø
9.52, gas
ø
12.7), the quantity of refrigerant to charge
additionally should be (10m
-
5m) x 0.06kg/m
=
0.3 kg.
<Where the existing unit can be run for a cooling operation.>
Car
ry out the following steps with the excising unit
(in the order of (1), (2), (3) and (4))
(1) Run the unit for 30 minutes for a cooling operation. (2) Stop the indoor fan and run the unit for 3 minutes for a cooling operation (returning liquid) (3) Close the liquid side service valve of the outdoor unit and pump down (refrigerant recove
ry)
(4) Blow with nitrogen gas.
※
If discolored refrigeration oil or any foreign matters is discharged by
the blo
w
, wash the pipe system or install a new pipe system.
• For the flare nut, do not use the old one, but use the one supplied with the outdoor unit.
Process a flare to the dimensions specified for R410A.
<Where the existing unit cannot be run for a cooling operation.>
W
ash the pipe system or install a new pipe system.
• If you choose to wash the pipe system, please contact our distributor in the area.
W
ARNING
※
Check with the flow chart developed for a case where an existing pipe system is reused for a twin-triple-double-twin model published as a technical data sheet.
INSTALLATION TEST CHECK POINTS
After installation
Power cables and connecting wires are securely fixed to the terminal block. The power supply voltage is correct as the rating. The drain hose is fixed securely. Service valve is fully open. No gas leaks from the joints of the service valve.
The pipe joints for indoor and outdoor pipes have been insulated. The reverse flow check cap is attached. The cover of the pipe cover (A) faces downward to prevent rain from entering. Gaps are properly sealed between the pipe covers (A) (B) and the wall surface / pipes. The screw of the side cover is tightened securely.
Check the following points again after completion of the installation, and before turning on the power. Conduct a test run again and ensure that the unit operates properly. Explain to the customer how to use the unit and how to take care of the unit following the instruction manual.
5. UTILIZ
ATION OF EXISTING PIPING