background image

14. Refrigerant charging 

 

When charging the air-conditioning system with refrigerant, it is important that oil is not 

pushed or washed away from the sump of the compressor; otherwise immediate damage to 

the compressor internal assembly will occur. To avoid this situation, the position of entry for the 

refrigerant to the compressor and system must be considered as follows; 

 

a)

 Most bus and coach applications have a system layout with the evaporator on the roof or at 

least in a position which is higher than the compressor. The preferred procedure for adding 

refrigerant and oil to the system is at this higher point. This will ensure the correct flow of 

refrigerant vapour and oil will pass through the compressor without any adverse effects to its 

initial operation. 

 

b)

 If it is not possible to access the system at the evaporator or roof level, then service points in 

suction and discharge lines away from the compressor are the next best option. 

 

c)

 If refrigerant must be added at the compressor, and there is no other alternative, only 

refrigerant vapour is to be added at the discharge and suction manifold valves at the side and 

top of the compressor (see diagram).  

 

d)

 Under no circumstances is refrigerant to be added at the R134a coupling service valves ( if 

fitted)  on the rear cap of the compressor. These valves are used for diagnosis only.

If any further assistance or information is required please go to www.unicla.hk

or contact your nearest Unicla dealer.

Charging at the compressor. 

Add vapour refrigerant only at 

manifolds (suction and discharge)

Do not add refrigerant at R134A 

coupling service valves (if fitted) 

Use for diagnosis only

Recommended points 

for charging the system 

(adding the refrigerant)

Unit

UWX

9.

Содержание UWX440

Страница 1: ...UWX550 and UWX440 Installation Guidelines...

Страница 2: ...ining professional information using representative graphs charts and tables Manufacturers specifications must be consulted for specific guidelines and performance data Unicla published data specific...

Страница 3: ...and screen 7 12 Oil injector 8 13 Discharge line analysis pressure and temperature 8 14 Refrigerantcharging 9 15 Compressor operation analysis report 10 Note This booklet is designed to assist the ins...

Страница 4: ...solid particle and chemical contamination before compressor fitting Solid particle contamination will cause direct compressor damage and starvation due to blocked system filters and screens see sectio...

Страница 5: ...the bolt then pull out Fig A Fig B Fig C 3 Fitting of discharge hose manifold Install the gasket Install Manifold Valve this is right hand view M10 x L60 Bolt Tightening tension 34 3 Nm 355 kg cm Con...

Страница 6: ...nd this amount is excluded from the quantities recommend above Note Oil quantity calculations are contained in the Unicla Service Handbook Total system oil requirement is based on 20 and 30 of refrige...

Страница 7: ...rvation of the compressor Warranty is void if these guidelines are not followed Unicla Oil Type Alternative Unidap 6 POE 68 Unidap 7 PAG 46 Recommended alternatives for Unicla Lubricant 6 Oil type and...

Страница 8: ...point Oil Green colouration exposure to copper oxidation Operation OK Recommendation Monitor oil condition and change if necessary Sight Glass Oil level low half point Oil Normal clean and transparen...

Страница 9: ...e Unicla inline mesh screen and filter insert should be used whenever there is risk of debris and fine particles entering the compressor through the suction line In the case of older systems where the...

Страница 10: ...ual is required or reference to additional technical information for specifications and faults regarding condensing to air differentials NR not recommended as a continuous running phase superheat may...

Страница 11: ...peration b If it is not possible to access the system at the evaporator or roof level then service points in suction and discharge lines away from the compressor are the next best option c If refriger...

Страница 12: ...ut oC Discharge Temp oC Pressure Drop Temp Difference oC Liquid Line Temp oC Suct LineTemp at Comp oC Discharge Superheat oC Evap Temp oC Condensor m s Subcooling oC Suct LineTemp at Evap oC Evap Duct...

Страница 13: ...Notes...

Страница 14: ...Unicla International Limited Unit 1209 1210 12F Manhattan Centre 8 Kwai Cheong Rd Kwai Chung N T Hong Kong Phone 852 2422 0180 Fax 852 2422 0680 Email sales unicla hk Website www unicla hk...

Отзывы: