AERMEC URX CF - Page 30

Heat recovery units with refrigeration circuit - URX_CF -
30
Selection and installation manual
GB
10. The compressor does not start due • Pressure switch out of order • Check and replace
to the intervention of the • Machine completely empty • See point 11)
low pressure switch • Poor air flow • Check the air duct and the state of
the filters.
• Blocked refrigerant filter • Check and replace
•The thermal expansion valve does not • Check, clean or if necessary
function correctly replace it.
11. Lack of gas • Leak in the refrigerating circuit • Check the refrigerating circuit
with a leak detector
12. Hot liquid pipe • Lack of refrigerant • See point 11)
13. The refrigerating circuit functions • Lack of refrigerant • See point 11)
correctly but with insufficient • Presence of humidity or incondensable • Replace the filter and if necessary
proficiency in the refrigerating circuit drain and refill the circuit
14. Compressor suction tube • Thermal expansion valve • Check the valve and
frosted if it is not working
correctly replace it
• Poor air flow • Check filters, fans and ducts.
• Lack of refrigerant • See point 11)
• Blocked liquid filter • Clean or replace
15. Abnormal noise in the system • Vibrations in the pipes • Secure the pipes
• Noisy compressor • Check electrical phases connection
• Noisy thermostatic valve • Check and add refrigerant
16. Evaporator coil • Lack of refrigerant in the circuit: • Check for leaks and eliminate them
before bubbles visible in the indicator.
topping up with refrigerant .
• Thermostatic expansion valve over . • Reduce the overheating of the
closed: suction pipe too hot thermostatic expansion valve
turn the valve stem and
check the suction pressure .
• Thermostatic expansion valve over . •
Change the valve or free the
closed: expansion valve bulb control pipe.
partially blocked or pressure intake pipe
blocked
• Filter-drier blocked: bubbles in the • Change the filter-drier.
flow indicator and liquid pipe colder
at the filter drier outlet
• The manifold feed pipes are • Remove the obstruction; clean or change
blocked or oil has accumulated in the the evaporator.
coil: not all of the evaporator circuits
are working
17. Compressor too hot •Thermostatic expansion valve • Reduce the overheating of the
over closed: excessive overheating thermostatic valve
of the evaporator discharge gas
18. Compressor to cold and noisy • Expansion valve over open: • Measure and reset the overheating
the system works with the overheating by closing the valve
to low (return of liquid to the compressor).
• Thermostatic valve out of order: the stem or • Replace the valve or free the
the seat of the expansion valve is pressure inlet pipe
corroded. Pressure inlet pipe blocked.
•
Foreign objects between the stem and the seat • Clean the stem and the holes of the
of the thermostatic valve: abnormal function thermostatic valve
of the thermostatic valve