What causes high discharge temperature on compressor?
What causes high discharge temperature? High discharge temperature is the result of temperatures in the compressor head and cylinders becoming so hot that the oil loses its ability to lubricate properly. This causes rings, pistons and cylinders to wear resulting in blow by, leaking valves, and metal debris in the oil.
How do you fix high temperature discharge?
Discharge temperature is greatly affected by the compression ratio, the larger the compression ratio, the higher the discharge temperature. Reducing the compression ratio can significantly reduce the discharge temperature, including increasing the suction pressure and reducing the discharge pressure.
What is the maximum compressor discharge temperature?
225 degrees F.
The limit to any compressor discharge temperature is 225 degrees F. If the discharge temperature gets higher than 225 degrees, the system may start to fail from worn rings, acid formations, and oil breakdown.
What causes high discharge pressure on ammonia compressor?
One common cause of high discharge pressure is the cooling medium (air or water) flowing across the condenser: either there is not enough or the temperature of the cooling medium is too high.
What causes high liquid line temperature?
High compression ratios from the low evaporator pressure will cause high heat of compressions, thus high discharge temperatures. High superheats. Both evaporator and compressor superheats will be high. This is caused by the TXV, evaporator, and compressor being starved of refrigerant from the liquid line restriction.
What causes high discharge superheat?
Other causes of high Discharge Superheat are a kinked or restricted liquid line, a restricted filter drier, a restricted Accurator piston or Accurator strainer or an Electronic Expansion Valve (EEV) under feeding the evaporator. Restricted condenser air flow can also contribute to high Discharge Superheat.
What temperature should the discharge line be?
It is desirable to limit discharge temperatures to below 250°F to 275°F (121°C to 135°C) to assure adequate packing life and to avoid lube oil degradation. At temperatures above 300°F (149°C), eventual lube oil degradation is likely, and if oxygen is present, ignition is possible.
What should be the discharge line temperature?
It is desirable to limit discharge temperatures to below 250°F to 275°F (121°C to 135°C) to assure adequate packing life and to avoid lube oil degradation.
How do you calculate the discharge temperature of a compressor?
For centrifugal compressor, the delta temperature can be calculated with 2 methods:
- Isentropic method where DT ideal= T1*[r^((k-1)/k)-1] and DT actual= DT ideal / ηis.
- Polytropic method where DT poly= T1*[r^((n-1)/n)-1]
What causes high suction temperature?
High suction superheat—common system conditions that cause increased suction temperatures are high thermostatic expansion valve superheat settings, ineffective or missing insulation and restricted thermostatic expansion valves.
What temperature should the liquid line be?
Also, note how much warmer the liquid line is than the outdoor temperature. It should be between 3°F and 20°F warmer than the outdoor temperature. If it is above or below that range, connect gauges.