Vacuum Drying - Toshiba MMY-MAP0804HT5P Manual De Instalación

Vacuum drying

Be sure to perform vacuuming from both liquid and gas sides.
Be sure to use a vacuum pump equipped with the counter-flow prevention function so that oil in the pump will
not flow back into piping for air conditioners. (If oil in the vacuum pump enters in the air conditioner with R410A
refrigerant, a problem may be caused in the refrigerating cycle.)
After finishing the airtight test and discharging nitrogen gas, connect the gauge manifold to the service ports of the liquid side,
gas side, and balance pipe side and connect a vacuum pump as shown in the figure below. Be sure to perform vacuuming for
the liquid, gas, and balance pipe sides.
Connected to indoor unit
Main pipe
Packed valve details
To outdoor unit
To gauge manifold
To
Gas-side valve
Liquid-side service port
outdoor
unit
Liquid-side valve
To
Balance
outdoor
service port
Gas-side
unit
service port
Piping at site
Piping at site
Balance
valve
Piping at site
Use a vacuum pump with a high vacuuming degree [-100.7kPa (5Torr, -755mmHg)] and large exhaust gas
amount (40L/minute or larger).
Perform vacuuming for 2 or 3 hours, though the time differs depending on the pipe length. Check that all the
packed valves at the liquid side, gas side, and balance pipe side are fully closed.
If the pressure does not reach -100.7kPa or less, continue vacuuming for 1 hour or more. If the pressure does
not reach -100.7kPa after 3 hours of vacuuming, stop vacuuming and check for air leakage.
If the pressure reaches -100.7kPa or less after vacuuming for 2 hours or more, close the valves VL and VH on
the gauge manifold fully and stop the vacuum pump. Leave it as it is for 1 hour to confirm that the vacuuming
degree does not change.
If the degree of vacuum loss is large, moisture may remain in the pipes. In that case, inject dry nitrogen gas and
apply pressure to 0.05MPa and perform vacuuming again.
After finishing the above procedure of vacuuming, exchange the vacuum pump with a refrigerant canister and
advance to the additional charging of refrigerant.
31-EN
1114208701-1 EN PT ES.indb 16 1114208701-1 EN PT ES.indb 16
Low pressure High pressure
gauge gauge
Packed valve fully closed
(gas side)
Gauge
V V
L H
manifold
Header outdoor unit
Service port
Brazed
Fully
closed
P
Service port
Vacuum pump
Packed valve fully closed
(liquid side)
Fully
closed
Service port
Packed valve fully closed
(balance)
Follower units
Adding refrigerant
After finishing vacuuming, exchange the vacuum pump with a refrigerant canister and start additional charging of refrigerant.
Calculation of additional refrigerant charge amount
Refrigerant charge amount at shipment from the factory does not include the refrigerant for pipes at the local site.
For refrigerant to be charged in pipes at the local site, calculate the amount and charge it additionally.
NOTE
If the additional refrigerant amount indicates minus as the result of calculation, use the air conditioner without additional
refrigerant.
Outdoor unit type
Heat pump
type
Charging amount (kg)
Additional refrigerant charge
=
Real length of liquid pipe
amount at local site
Table 1
L q i u d i p p i e d a i ( . m m ) 6 4 .
Additional refrigerant amount/1m liquid
0.025
pipe (kg/m)
– 16 –
MAP080 MAP100 MAP120 MAP140 MAP160
11.5
Corrective amount of refrigerant
Additional refrigerant charge
depending on HP of co-
× +
amount per 1m liquid pipe
operating outdoor units
(Table 1)
(Table 2)
9 5 . 1 2 7 . 1 5 9 . 1 9 1 .
0.055 0.105 0.160 0.250
2 2 2 .
0.350
EN
ID
ID
32-EN
02/27/14 1:39 PM 02/27/14 1:39 PM