PREMIUM PRF071XW (01) PDF DOCUMENT

Model	Door	Gasket seal for the door	Hinge	Accessory	Structure
PRF047XW PRF071XW	Integrated Foaming Door with painting sheet metal and simple, beautiful recessed handle	Recessed door gasket seal, easy to be discharged and cleaned.	Plastic material, simple and practically	One shelf and one drip tray inside	Front, Left and right side shell compose to whole “U” shape shell, with aluminum internal tank with cotton ginning, and unitary plastic linear mouth. It has inside hidden evaporator and condenser, and unitary foaming insulation.

No.	Model	PRF047XW	PRF071XW/PRF3X-3XT
1	Net Capacity (L)	47	71
2	Voltage (V)	115	115
3	Frequency (Hz)	60	50
4	Refrigerant	R134a	R134a
5	Refrigerant Amount (g)	38g	45g

In order to be safe during maintenance, you must obey the following basic attention:

1) During service:

Pay attention to the flame or ignition nearby, particularly after welding using gas. You must turn off the flame first, then you can do other maintenance work, because the refrigerant will produce toxic air when it touches a flame, sparkle or capacitor.

Do not do the welding work in an airtight or bad air circulation room.

When discharging the refrigerant, you must keep the room in good air circulation condition.

When cutting the suction pipe or discharging pipe of the compressor, pay attention to the surplus refrigerant and internal pressure in the cooling system pipe.

2) Unplug the unit:

When you are ready to proceed with maintenance, you must first unplug the freezer to ensure safety.

3) Avoid electrical shock:

Normally when proceeding with maintenance, you must open the power supply first. But if you must check the field wiring or a component of the unit with the power supply on, you must be very careful and do not touch the live parts. If you find out the wiring is aged, please replace it in time.

4) Correct use of components:

If a component is damaged and needs to be replaced, be sure to replace it with a component of the same model. Do not use other models or other brand components, and do not use a changed component.

5) Correct use of service tools:

Ensure to use the appropriate service tool. Otherwise it will cause bad electrical contact or loose fixing, and an incident will happen.

6) Wiring connection:

When re-connecting a cut wire, be sure to use a soldering method or terminal connection, and then wrap the connection point with insulation tape to ensure a good connection.

7) Insulation resistance measure:

After completing the service and assembly, you must use a multi-meter to measure the insulation resistance. If it is greater than 1 million ohm, then you can plug in the unit.

8) Grounding test:

After maintenance, use the multimeter to measure the grounding resistance to ensure the grounding resistance is less than 0.1 ohm.

9) Pay attention to the child or infant nearby:

During maintenance, do not let a child or infant be nearby.

10) Cleaning:

After service, do the necessary cleaning work and tell the customer the necessary precautions.

The electrical diagram illustrates the connections between the key components:

The POWER PLUG (L, E, N terminals) connects to the system.

A black wire goes from the L terminal to the THERMOSTAT.

A red wire connects the THERMOSTAT to the OVERLOAD PROTECTOR.

The OVERLOAD PROTECTOR connects to the C terminal of the COMPRESSOR.

A white wire from the N terminal of the POWER PLUG connects to the PTC STARTER.

The PTC STARTER connects to the S and M terminals of the COMPRESSOR.

Yellow/green wires provide grounding for the THERMOSTAT, POWER PLUG (E terminal), and COMPRESSOR casing.

Please note, some units may be without the RUNNING CAPACITOR, which is sometimes marked in red on diagrams.

The refrigerant flows through a closed loop system. The flow direction is as follows:

1. The Compressor pressurizes the refrigerant.

2. The high-pressure refrigerant flows through the Condenser, where it releases heat and condenses into a liquid.

3. It then passes through a Dry Filter to remove moisture and impurities.

4. The liquid refrigerant moves through the narrow Capillary tube, which causes a drop in pressure and temperature.

5. The low-pressure, cold refrigerant enters the Evaporator inside the fridge, where it absorbs heat from the compartment and evaporates back into a gas.

6. The gas is drawn back to the Compressor through the Air Suction Pipe, and the cycle repeats.

No.	Parts Name	PRF047XW	PRF071XW/PRF3X-3XT
1	Door	1	1
2	Hinge	2	2
3	Shelf	1	2
4	Freezer Cabinet	1	1
5	Thermostat cover	1	1
6	Compressor base	1	1
7	Condensate Water Drain cap	1	1
8	Fixing feet	2	2

When replacing components, you must unplug the unit first in order to be safe.

1) Replace the thermostat:

Unscrew the fixing screw of the thermostat box, remove the thermostat box, then remove the old thermostat, install the new thermostat with the same model, and reinstall back the whole thermostat box with the same fixing screw.

2) Replace the PTC starter and overload protector of the compressor:

Remove the clamp of the connecting terminal cover of the compressor and the terminal cover, toward the vertical direction. Remove the broken-down starter or overload protector, install back the new starter or overload protector, then fix back the terminal box cover and its clamp.

3) Replace the door gasket seal:

Remove the old door gasket seal from the groove of the door liner. Then install the new gasket seal into the four sides of the groove. Install it as evenly as possible. Open and close the door several times to ensure that the door is sealed.

4) Replace the compressor:

(a) First, cut the welding point of the technical pipe of the compressor to discharge the refrigerant inside the cooling system. Then, weld the old point to disconnect the pipe to the compressor. Remove the compressor to replace it with a new one, paying attention to replace it with a new refrigerant dry filter.

(b) Install the new compressor, weld the high-pressure side and low-pressure side pipe to the compressor, and check the system for leakage. After completing a vacuum of the cooling system, charge the correct amount of refrigerant into the system from the low-pressure side pipe. After this, run the unit to check if the cooling performance is ok. Then, weld and close the technical pipe.

Check the frost on the cabinet liner surface and follow these steps based on your findings:

1) No frost, then do the leakage detecting.

A) If a leakage point is found, first cut off the low-pressure pipe to discharge the left refrigerant in the system. Then clean the pipe, replace it with a new dry filter, and weld again. Recharge the refrigerant and do the leakage detecting again.

B) If leakage cannot be found, cut off the low-pressure pipe. If there is no refrigerant omitting, then recharge the refrigerant and do the leakage detecting again. If there is refrigerant omitting, cut off the high-pressure pipe (means that compressor suction is normal), and charge the condenser pipe with pressurized nitrogen. If no air is at the low-pressure side, it means the pipe is blocked; replace the blocked parts and clean the system pipe. If there is no air suction at the compressor low-pressure side, cut off the high-pressure pipe; this means air compression of the compressor is not good, please replace the compressor.

2) A little frost on the surface, also do the leakage detecting first.

A) If the leakage point is confirmed, then cut off the low-pressure pipe. If a little refrigerant air spurts out, it means that the system leaks slowly on the leakage point. You should repair the welding of the cut pipe and the leakage point and clean the system pipe with high-pressure nitrogen. Replace the dry filter. After completion of this work, re-vacuum and recharge the refrigerant. At last, do the leakage detecting again.

B) If a big quantity of refrigerant spurts out, cut off the high-pressure pipe to check the suction of the compressor low-pressure pipe. If there is no suction or weak suction, it means not good compression and you need to replace the compressor. If there is normal suction, then charge the clean and warm nitrogen to the condenser pipe. If you find the returned nitrogen of the low-pressure side is not sufficient, it means that the system pipe is clogged lightly; please replace the clogged parts and clean the pipe.

3) No frost, but have condensate water on the surface of the cabinet liner.

Check the temperature of the high-pressure side pipe and the compressor. You will find it is too high, and if you check the low-pressure pipe, you will find frost. This means there is too much refrigerant in the system. Please recharge with the appropriate quantity of refrigerant once more.

4) The unit works discontinuously.

Maybe the system is clogged with ice. Please replace the dry filter and clean the system with clean and warm nitrogen.

5) Compressor doesn’t run.

Please check the electrical parts, such as the PTC starter, capacitor, overload protector, thermostat, etc. If you find the parts are wrong, then replace them with a new one of the same type and specification. If all of these parts are good, please measure the resistance of the compressor winding. If the resistance is abnormal, you must replace the compressor. Otherwise, check if the overload protector acts or not. This could mean there is an over-large current and the compressor is faulty; also, replace the compressor.

Item	Phenomenon	Check point and the detail	Caused by
(A). Not cool completely	Power indicator is not on and compressor doesn’t run	No power supply in neighbor house	Field power supply is cut off.
		All of other appliances in house don’t work	Main fuse is cut off.
		Only this freezer doesn’t work	Power supply outlet has problem
	Compressor doesn’t run, but power indicator is on.	If the cooling thermostat is shorted of the circuit or turn the thermostat to the coldest point, the compressor can run.	Thermostat is breakdown
		There is sound when turning the knob of the thermostat.	The knob is broken or is not installed properly.
		Thermal protector may be overloaded. Check it is cutoff or not by the multi-meter.	If it is cutoff, it means it is broken down.
		PTC Starter. Check it is cutoff or not by the multi-meter.	If it is open, it means it is broken down.
		Check the circuit wiring. Check if there is a broken point or not in the circuit wiring according to the electrical diagram.	Maybe the lead is broken or the connection point is loose.
	Compressor can run but cooling effect is not good.	Compressor problem. Measure the winding resistance of the compressor.	The winding is broken or burnt.
		Measure the insulation resistance by meg-ohm meter, if the insulation resistance < 1 MΩ, the unit can't be used for long time.	The winding is burnt.
		Power supply voltage. The voltage is too low (Maybe lower than 175V).	Compressor can’t start because of under voltage.
		Cooling system. There is no sound of refrigerant flowing in cooling system and it leaves oil on the welding point.	Leakage of refrigerant.
		Cooling system. There is no sound of refrigerant flowing in cooling system and no oil on the welding point.	Inside leakage of cooling pipe or the pipe is blocked.
		Compressor. No air is discharged out on the discharging mouth of the compressor.	Compressor valve is breakdown.
(B). Compressor	Incorrect using	Check the thickness of frost (>5mm?)	The frost is too thick
(C). Temperature is too low	Abnormal action of thermostat	Check the sensor head of the thermostat is losing or not	Incorrect temperature sensing of thermostat
		Thermostat is set at higher temperature (lower digit)?	Set it to lower temperature
		Thermostat is not at good quality	Thermostat is breakdown
(D). Water condensate	There is condensed water on the closure	The environment is too wet	The relative humidity is too high
(E). Leakage of electricity	Electrical shock sense on the enclosure	Confirm the insulation resistance is lower than 1 MΩ by the meg ohm meter	Insulation is not good
		Check the electrical parts of the unit are wet	Insulation is not good
		Check the electrical parts touch with the metal enclosure or not, and the grounding lead is not grounded properly	Electricity leakage
(F). Too noisy and vibration	There is sound inside compressor	Check the compressor has abnormal sound or not.	Compressor abnormal
	There is vibration sound	Check the pipe is touched each other or not	Pipe touching produce resonance
		Check the installation ground is flat and the feet is adjusted at proper position or not	The unit is not placed evenly

Because refrigerant R134a and its lubricating oil have strong water absorbability and oxidation ability, which can cause impurities, you should pay close attention to water, oxide, chloride, oil, and impurity quantities in the cooling system.

1) The requirement of the cooling system parts:

Left water quantity control:

a) If cooling system parts like the condenser, evaporator, compressor, or dry filter need to be replaced, the replaced parts should be stored charged with dry nitrogen with a pressure of 0.2-0.3Mpa. If these parts have leakage of nitrogen, they must be dried in a high-temperature chamber and be taken out of the water before using.

b) The molecular dry desiccant inside the dry filter must be controlled strictly, guaranteeing that the left water quantity must be lower than 1.5WT%. Normally, after the dry filter is opened from its vacuum package, it must be welded to the pipe system within 5 minutes. In wet conditions (relative humidity >50%), you must take measures to protect it from humidity, and the dry filter must be connected to the system pipe at once after removing it from the package to produce a sealing system.

2) The requirement of the service equipment:

① No need for recycling equipment, except a charging machine. If the equipment is special for the R134a refrigerant system, you must mark it clearly to avoid using it with other refrigerants (except welding machine, pliers, electronic balance).

② The vacuum machine and charging machine are for special use with the R134a refrigerant system.

Special requirement during service process:

(a) The duration from the opening of the compressor to the vacuuming process must be less than 10 minutes, and for other parts, not more than 12 minutes.

(b) Vacuuming duration should not be less than 20 minutes.

(c) If refrigerant leakage happens, it needs to replace the compressor. Before welding, dry the cooling system with nitrogen air.

(d) If dust blockage happens in the cooling system pipe and can be blown out by nitrogen, you do not need to replace the compressor. Otherwise, the cabinet is not useful (and the evaporator is not useful).

(e) If ice blockage happens in the system pipe, you must replace the compressor.

(f) Change the dry filter only if the system is opened.

Main point of service:

① The replaced compressor must be returned to the compressor manufacturer to be treated.

② The compressor can’t be tested through direct absorbing atmosphere; it will damage the compressor.

③ If the system pipe is opened for a long time or leakage happens, you can dry the system by nitrogen during service.

④ All of the welding material must be protected from wet conditions. And ensure to use as little as possible.

⑤ Check if the compressor is pressurized or not when opening.

⑦ When storing the R134a refrigerant, you must keep it sealed and not in contact with the atmosphere directly.

After completing the service, it normally needs to be test run for 1-2 days. When it is proved to be safe and have good cooling performance, then move it to the customer or user. During test running, we suggest that you do the following:

1) Insulation and safety:

Before plugging in, use a DC 500 meg-ohm meter to measure the insulation resistance between the live parts and the dead metal enclosure. Ensure the result is not lower than 1 meg-ohm.

2) Starting capability:

The compressor should start smoothly and can start or stop normally. If the unit can’t start or stop normally, you must find the root cause and delete it, then you can plug it in to let it run.

3) Cooling performance:

After running for 24 hours, check that the frost on the surface of the cabinet liner is even or not, and there is no frost on the suction pipe.

4) Electrical structure and safety:

After service, check all of the electrical parts. Ensure the connection terminals of the electrical parts do not loosen and the grounding wire is ok.

5) Leakage checking:

After running for 24 hours, check one by one of the welding points by using a halogen leakage detecting device or suds. If leakage happens again, then service should be performed again.

No.	Parts name	PCS/unit	Note
1	Compressor	1
2	Thermal protector of compressor	1
3	PTC starter	1
4	Feet of compressor	4
5	Refrigerant dry filter	1
6	Thermostat	1
7	Power cord assembly	1
8	Adjustable feet	4
9	Door gasket sealing strip	1
9	Running indicator	0
10	Power indicator	0