In the case of pressure decrease during steps 1 to 3 ,check the joints with the ear,hand or soapsuds for
Repair it by welding or tighten the connecting nut up.
Use vacuum pump to evacuate the air.Never use the refrigerant for the evacuation.
Drain off the nitrogen gas after the leak test and then connect the vacuum pump as shown in the figure below.
The vacuum pumping must be done from both the liquid and gas inlets.
Check for leakage
Vacuum Pumping
Use a vacuum pump with high degree of vacuum(below-755mmHg) and large volume displacement
40L/min)
The pumping time depends on the length of the connecting pipe.Generally,it takes about 2-3 hours.
Make sure that the Y-shaped valves on both the gas and liquid sides are closed before pumping.
If the vacuum can no reach-755mmHg within 2 hours,continue pumping for another 1 hour.
If the vacuum can no reach-755mmHg after more than 2 hour's pumping,close the valves VL and VH
gauge distributor and stop pumping.One hour later,check the vacuum again.If the
there is a leakage.Repair it.
After the above steps,replace the vacuum pump with the refrigerant pump and refill refrigerant.
To the unit
To the unit
(Gas side)three-way valve
(Gas side )access hole
Detailed diagram of the
three-way valve
To the gauge
distributor
(Liquid side)access hole
Three-way valve fully closed
liquid side
6.4
Copper pipe
Vacuum pump
Gauge distributor
High-pressure
gauge
Low-pressure
gauge
Three-way valve fully
closed(gas side)
Solder joint
Solder joint
Tightly
closed
Indoor unit
Indoor
Outdoor
Access hole
Solder joint
Tightly
closed
Tightly
closed
Access hole
Outdoor unit
(Liquid side)three-way valve
Field tube
installation
Field tube
installation
P
Charging refrigerant
Refrigrant must be charged in liquid state.
Refrigerant bottle with or without a siphon
tube can be refilled with refrigerant upright
or upside down,Respectively.
Containers for R
22
refrigerant must be
marked with R
22
and a brown Stripe.
R407C refrigerant cannot share the same
instrument distributor and filling pipes.
leakage.
(above
on the
vacuum has changed,it means
Refilling of refrigerant
After the vacuum pumping,replace the vacuum pump with the refrigerant pump and refill refrigerant.
Calculation of refrigerant quantity
The factory filled refrigerant into the piping excludes the part of pipes according to be refilled on the site.
Refill the amount of refrigerant into the piping according to the following formula.
The factory filled refrigerant is listed in the table below:
The quantity of the refrigerant to be refilled during installation depends on the diameter and length of the liquid piping.
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Installation