If an internal equalizing expansion valve is substituted with an external equalizing valve, an additional connection must be provided for the external equalizing capillary. The…
When this condition exists there is effectively a total blockage in the high side of the system (liquid line). The pressure in the low side…
There are a number of reasons for replacing an expansion valve: 1. Mechanical failure of the valve: possible seizure of the valve stem carriage; worn…
Some commercial evaporators are designed with series-parallel and parallel tubing circuits, which means that they have more than one refrigerant circuit. Refrigerant from a single…
When flooding of the evaporator takes place, frosting along the suction line will be evident. This is caused by the liquid refrigerant boiling off and…
A low evaporating pressure can be due to pressure drop through the evaporator caused by friction, the length of the evaporator tubing, and the number…
Manufacturers will stipulate the setting of new expansion valves. They are generally set to maintain a superheat of 3.5 to 5o C or 7 to…
Generally the performance of the thermostatic expansion valve depends upon the correct location of the thermal bulb. This should be clamped firmly to a horizontal…
It is recommended that a quick acting indicating thermometer be used. Two thermometer probes must be firmly attached to pipework free of frost or ice…
When a plant has been charged it must be established that the charge is in fact complete. The disappearance of bubbles in a sight glass…