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ENVIROFRESH   

 

 

 

 

 

SHC/TA    

 

Troubleshooting – Refrigeration 

 
   FAULT 

   POSSIBLE CAUSE    REMEDY / ACTION

 

 

 

Suction pressure too low. 
 
 
 
 
 
Insufficient cooling 
(High suction, low head) 
 
Insufficient cooling 
(Low suction, low head) 
 
 
 
 
Insufficient cooling(High 
suction, low superheat) 
 
Insufficient cooling 
(Low suction, high head) 
 
 
 
Insufficient heating (low 
suction, low head) 
 
 
 
 
 
 
Insufficient heating (High 
suction, low superheat) 
 
 
Insufficient heating (low 
suction high head) 
 
 
 
 
System not changing over 
to heating 
 
 

 
 

Reduced airflow. 
 
Clogged filter drier. 
 
Obstruction in expansion 
valve. 
 
4 port valve not fully 
engaged or internal leak. 
 
Icing coil. 
 
 
Low on refrigerant. 
 
 
Indoor check valve leaking. 
 
 
Outdoor check valve not 
fully open.  
 
 
Icing coil. 
 
Low on refrigerant. 
 
 
4 port valve not fully 
engaged or internal leak. 
 
Outdoor check valve 
leaking. 
 
 
System overcharged. 
 
 
Outdoor check valve stuck 
closed. 
 
4 port valve not operating 
or stuck. 
 

Check volumes, change filters. 
 
Replace. 
 
Inspect, clean or replace. 
 
 
Try to free by valve by operating or 
replace. 
 
Check air volume and indoor frost stat. 
 
Check for leaks- repair and recharge 
system 
 
Replace. 
 
 
 
Replace. 
 
 
 
Check air volume and de-frost stat. 
 
Check for leaks- repair and recharge 
system 
 
Try to free by valve by operating or 
replace. 
 
Replace. 
 
 
 
Reduce charge. 
 
 
Replace. 
 
 
Defective solenoid. Replace. Check 
control feed. Try to free by valve by 
operating or replace. 

Summary of Contents for Envirofresh Series

Page 1: ...ANCE INSTRUCTIONS FOR SERIES ENVIROFRESH AIR HANDLING UNITS CONTRACT No PROJECT REF AIR HANDLERS LIMITED Alfred Proctor House Bute Street Weaste Salford M50 1DU TEL 0161 745 8888 FAX 0161 925 9900 mai...

Page 2: ...electric motor s the procedure as laid down in this manual is fully carried out The procedure for removing and replacing timing wedge belts and filter media bags or panels are fully carried out as la...

Page 3: ...also essential for service and maintenance purposes and for the removal of the motor s INSTALLATION All units must be installed in accordance with good engineering standards upright and levels on a p...

Page 4: ...ed to prevent damp and ingress of dust or foreign bodies and held in a dry store Fan Shaft Bearings Refer to Bearing damage in Cautionary Notes Bearings fitted with shields should not be stored for pe...

Page 5: ...ation drive belts should be checked for tension and re tensioned if required Maintenance At least every 12 months a major inspection of the fan section should be carried out as follows Isolate electri...

Page 6: ...motors are shipped with sufficient grease for a long operating period if relubrication is needed using a low pressure hand operated grease gun pump in clean recommended grease until the new grease app...

Page 7: ...et the lower marker ring at the deflection distance required in mm on the lower scale Set the upper marker ring against the bottom edge of the tube Place the belt tension indicator on top of the belt...

Page 8: ...n bends of the coil Damage to fins can be corrected by use of a fin comb available from Air Handlers all coils should be installed level and upright unless otherwise specified Care must be taken to en...

Page 9: ...um breakers must be installed between the coil and the trap inlet to ensure that the hydraulic head drain the coil when it is at atmospheric or sub atmospheric pressure The vacuum breaker should respo...

Page 10: ...ot twisted by ductwork and that fixings do not penetrate cog housing of the damper which will affect the damper mechanism Ductwork must be independently supported and should not be left to hang from t...

Page 11: ...rried out This should generally be carried out at least every six months and a service inspection sheet issued to the customer upon completion Log books should be kept on site by the end user to prove...

Page 12: ...pproval of AIR HANDLERS LIMITED Damage caused to equipment on site through lack of adequate protection from the elements or misuse by other trades Failure to observe all normally accepted engineering...

Page 13: ...S manifold and compare them with the commissioning sheet If there is any significant variation then the fault should be found and corrected Refer to the troubleshooting chart If on inspection of the r...

Page 14: ...k isolator mains supply Check settings Inspect fireman s panel Check actuator operation and end switch making when open Check control switch fuses MCB s and control circuit wiring Inspect drive belts...

Page 15: ...mpressor section Check operation and settings Check operation and settings of the indoor frost protection stat Check fan runs on to dissipate heat prior to unit shut down Replace if faulty and reset h...

Page 16: ...d control circuit wiring Step energised on controller Check air flow failure switches Check delay timer operation check controller timer operation Change compressor Check winding resistance replace co...

Page 17: ...or internal leak Icing coil Low on refrigerant Indoor check valve leaking Outdoor check valve not fully open Icing coil Low on refrigerant 4 port valve not fully engaged or internal leak Outdoor chec...

Page 18: ...it is the installers responsibility to ensure correct lagging Installers Responsibility Installation Unless otherwise specified by ourselves this product is supplied with the intention to be incorpor...

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