Room Two Temperatures, Valves
They maintain a high pressure refrigerant in one or more evaporators several evaporator system. This pressure is higher than the pressure in the rest of the system. Four types of two-temperature valves:
- Metering.
- Instantaneous.
- Thermostatic.
- Solenoid valve, thermostat controlled.
Four trouble that often come with valves are:
- Leaky needle.
- The valve is stuck shut.
- Valve correction.
- Frost accumulation on the furs.
If the valve flows, warm evaporator will be too cold. There will be danger of freezing. Cold temperatures may also be due to other causes, including adjusting the two-temperature valve too close and the pressure is too low. To determine which of two evils is present, check to see if the valve is adjusted recently. If the valve has not been tampered with, the problem is probably leak needle. If the valve has been tampered with, it needs to be fixed. The thermometer is used to obtain the correct temperature of the evaporator.
Adjusting nut should not be turned more than half of the turnover. 15-minute interval must be solved between each setting. This allows the evaporator to fully satisfy the new pressure.
Low pressure sensor must be installed in the evaporator side of the valve. This allows exactly making adjustments for two-temperature valves. Sometimes this intrusion, but in many cases it is not. When two temperature, valves, you must install a shutoff valve. He must have a sensor open in the suction line. This will use the sensor to verify the evaporator low-pressure side. This process wrill do service work on such valves easier.
It is rare to have a valve stuck shut. It is easily recognized by a lack of cooling in warm evaporator. Lack of adequate supply of the refrigerant in two-temperature valve (not by him). To check the refrigerant supply, crackling torch nuts on the high pressure of the two-temperature valve. Some of these two-temperature valves screens. Score screen will be shown with the help of warm cooling conditions of the evaporator. Symptoms will appear stuck needles condition.
Frost settles on the bellows if the valve is located in or near the freezer. The valve must be removed from the freezer. Bellows should be covered with a light grease. The same troubles are instantaneous, two-temperature valve as with a metering valve. However, most of the snap-action valves have a connection of the sensor. This connection of the sensor produces adjustment valve simple. Therefore, it can be determined if the valve is leaking or correction.
Thermostatic two temperatures, the valves have the same troubles, causes and remedies, as the other two. In addition, they had problems with thermostatic element. These problems are the same as already mentioned, for thermostatic valves. They are:
- Loss free with a thermostatic element.
- Frost on the furs.
- Poor contact between the authorities and the evaporator.
- Pinched capillary tube.
- Improper Adjustment.
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Industrial