Cooling system pressure and temperature of evaporation and condensation pressure and temperature are the main parameters. Operation and adjustment is an important basis, according to the practical condition and system change, adjustment and control of operating parameters, make it run under the economical and reasonable parameters can ensure the safety of machinery and equipment and storage products,give full play to efficiency, and saves water, electricity, oil, etc.

, Caused the evaporation temperature is too low and the solutions

One reason: the evaporator (cooler) is too small

Design Shi has problem, or actual storage varieties and design plans storage varieties different, hot load increased, like, intends storage Apple of cold storage, for storage garlic, due to a region of garlic harvest period only days time, cannot do with Apple as daily of purchase volume by library capacity of 5%-15%, but 3-5 days will into full, so, as to timely put temperature down to suitable storage temperature only by reduced evaporation temperature to achieved.

Solutions: increasing the evaporator area or replace the evaporator.

Two reasons: the compressor cooling capacity is too large

Warehouse load decreases and then failing to reduce the energy of compressor. Refrigeration system of refrigerator compressor is based on matching the maximum load, and fruit and vegetable cold storage warehousing of the goods is the biggest load stage, the other most of the time, the load on the compressor is less than 50%.When the storage is over after the temperature dropped below the optimum storage temperature, load greatly reduced, if still open larger machines, which formed a large horse-drawn trolley, temperature increases, consumption increases.

Solution: load changes should be based on the Treasury to reduce the compressor turn on number or with the energy regulator reduce the number of operating cylinder.

Three reasons: evaporator not defrost

Coefficient of heat transfer of evaporator coils frosting to make it smaller, increasedthermal resistance, lower heat transfer efficiency, refrigerant evaporation reduction in compressor energy the same cases, will lead to the evaporation pressure, corresponds to the evaporation temperature, so time to defrost.

Solution: defrost in a timely manner.

Four reasons: evaporator in lubricant

Oil would evaporate in the evaporator coil on the tube wall forming a film of oil, willalso make heat transfer coefficient decreases, increased thermal resistance, lower heat transfer efficiency, refrigerant evaporation is reduced, resulting in reduced the evaporation pressure, corresponds to the evaporation temperature.

Solution: the drain of the system in a timely manner, and use hot ammonia defrosting out of the lubricating oil in the evaporator.

Reason five: expansion valve is too small

Expansion valve opening is too small, the system for the small amount of liquid, unchanged at compressor energy case, evaporation pressure, result in a lower evaporation temperature.

Solution: the expansion valve opening degree should be increased.

Second, causing reason and solution to the condensing pressure too high

Condensing pressure will lead to increased compression, cooling capacity reductioncoefficient decreased energy consumption increase. It is estimated that in the case of other conditions do not change, the condensing temperature for condensing pressure per 1 c, power consumption will increase by about 3%. Generally considered more economical condensing temperature 3~5℃ higher than the cooling water outlettemperature.

Causes condenser pressure lifting causes and solutions:

1, the condensers selected was too small. Replacing or increasing the condenser.

2, small number of condenser running. Increasing the number of runs.

3, insufficient flow of cooling water. Increase the number of heat pumps to increasewater flow.

4, cooling water temperature too high. Added low temperature water (tap water or wells); using rushed cream water; guarantee cooling tower of cooling effect, cooling tower is in outdoor installation, due to wind machine of role, will has large of dust, and leaves, and insects, into Tower within, time long has will caused cooling tower filler, and pipeline, of jam, addition using time long has, cloth water device spray hole also will was debris or scale jam, effect cooling effect, thus needed on cooling tower regularly cleaning, keep clean. Should be closed when the water temperature is close to the wet-bulb temperature of the air, reducing power consumption of cooling tower fan.

5, the condenser heat transfer area. Adequate heat transfer area is the condenser heat exchange efficiency is an important safeguard. Especially used compression condensation unit of refrigeration system, because this unit of condensation device and has storage liquid device of function, dang condensation device within liquid bit high Shi, serious effect condensation device of condensation effect, condensation temperature and pressure increased, refrigeration compressor power consumption increased, so, operation Shi should note liquid bit changes, timely emissions condensation device in the of condensation liquid, raises refrigeration agent Shi, strictly control joined volume, ensure condensation device sufficient of for hot area.

6, condenser water not uniform. Even when water comes, some water maximum flow in the pipe, part of the water flow in the pipe, will reduce the heat transfer efficiency, condensing temperature. Good water distribution, water flow along the wall rotated, if water flows from the tube down in the Middle, most water doesn't condenseeffect. So when the water distributor water when not in uniform, should replace water Distributor.

7, condenser pipe scale. Condenser pipe on the thermal resistance of scale lead to increased heat transfer coefficient, heat exchange effect, condensing temperature torise. Improvement of water quality, scale removal in a timely manner.

8, there is air in the condenser. Condensers air system pressure increases, the total pressure, air and gas layer is formed on the surface of the condenser, heat resistance,heat transfer efficiency, leading to condensation pressure condensation temperature. Time on air.