Friedrich kuhl r-410a ユーザーズマニュアル

45

8.   Pressurize sealed system with a combination of R-410A 

and nitrogen and check for leaks, using a suitable leak
detector. Recover refrigerant per EPA guidelines. 

9.    Once the sealed system is leak free, install solenoid coil
       on new valve and charge the sealed system by weighing   
       in the proper amount and type of refrigerant as shown
       on rating plate. Crimp the process tubes and solder the
       ends shut. Do not leave Schrader or piercing valves in
       the sealed system. 

 When brazing a reversing valve into the system, it is 

of extreme importance that the temperature of the valve does 
not exceed 250

°F

 at any time.

Wrap the reversing valve with a large rag saturated with 
water. “Re-wet” the rag and thoroughly cool the valve after 
each brazing operation of the four joints involved.

The wet rag around the reversing valve will eliminate 
conduction of heat to the valve body when brazing the line 
connection.

6.       Protect new valve body from heat while brazing with  plastic

heat sink (Thermo Trap) or wrap valve body with wet 
rag.

7.  Fit all lines into new valve and braze lines into new  

valve. 

Procedure For Changing Reversing Valve 

1.     Install Process Tubes. Recover refrigerant from sealed

 system. PROPER HANDLING OF RECOVERED
 REFRIGERANT ACCORDING TO EPA REGULATIONS
 IS REQUIRED. 

2.   Remove solenoid coil from reversing valve. If coil is to

 be reused, protect from heat while changing valve. 

3.     Unbraze all lines from reversing valve.

4.   Clean all excess braze from all tubing so that they will

 slip into fi ttings on new valve. 

5.    Remove solenoid coil from new valve.  

The use of a torch requires extreme care and proper 

judgment. Follow all safety recommended precautions 

and protect surrounding areas with fi re proof materials. 

Have a fi re extinguisher readily available. Failure to follow 

this  notice  could  result  in  moderate  to  serious  property 

damage.

 

The only definite indications that the slide is in the mid-
position is if all three tubes on the suction side of the valve 
are hot after a few minutes of running time. 

NOTE: A condition other than those illustrated above, and  
on Page 44, indicate that the reversing valve is not shifting 
properly. Both tubes shown as hot or cool must be the same 
corresponding temperature. 

Certain unit components operate at 

temperatures hot enough to cause burns.

Proper safety procedures must be followed, 

and proper protective clothing must be 

worn. 

Failure to follow these procedures could 

result in minor to moderate injury.

The use of nitrogen requires a pressure

regulator. Follow all safety procedures and 

wear protective safety clothing etc. 

Failure to follow proper safety procedures 

could result in serious injury or death. 

Sealed Refrigeration System contains refrigerant 

and oil under high pressure.

Proper safety procedures must be followed, 

and proper protective clothing must be worn 

when working with refrigerants.

Failure to follow these procedures could 

result in serious injury or death.