Quincy Compressor QGS 90, Инструкция

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Thermostat BV1 starts to open at 75 ˚C (167 ˚F) and is completely open at 90 ˚C (194 ˚F).
Energy recovery system in use (see drawing)
The wheel (V1) of BV2 (bypass valve of the HE) is totally turned in clockwise .
• Compressor start-up
When the compressor is started up from cold, the oil temperature will be low. Bypass valve (BV2)
shuts off the oil supply through the heat exchanger (HE) and bypass valve (BV1) shuts off the oil
supply through the oil cooler (Co) to prevent the compressor oil from being cooled. The oil flows
from the oil separator vessel (AR) through the oil filter(s) (OF) back to compressor element (E).
All energy input is used to rapidly warm up the compressor oil. No energy is recovered.
• Maximum energy recovery
As soon the oil temperature reaches the set point (opening temperature) of bypass valve (BV2),
the valve starts closing off the bypass over the heat exchanger (HE) oil line, gradually allowing
the oil to flow through the heat exchanger (HE). As the oil temperature rises to approx. 15 ˚C (27
˚F) above the set point, all the oil passes through the heat exchanger. The exchange of heat
between the compressor oil and the heat recovery water is maximum. The oil from the heat
exchanger outlet flows via oil filter (OF), oil stop valve (Vs - if present), compressor element (E)
and separator (AR) back to the inlet of heat exchanger (HE). Bypass valve (BV1) bypasses the
oil cooler (Co) as long as the oil temperature remains below its set point.
Operation principle at different loads:
• Low consumption of recovered energy
The temperature of the oil leaving heat exchanger (HE) rises. When the temperature rises
above its set point, oil cooler bypass valve (BV1) will gradually allow the oil to be cooled in
the oil cooler (Co).
• Recovery water flow too high/temperature too low
In this case, bypass valve (BV2) will open the bypass line allowing oil from heat exchanger
(HE) to be mixed with oil from separator (AR). Energy is transferred from the compressor oil
to the water, but at a relatively low temperature level.
Energy recovery system not in use
The wheel (V1) is completely turned out anti-clockwise .
The oil circuit is the same as without installation of the energy recovery system.
No energy is recovered.
This situation should be considered as exceptional, e.g. in case of maintenance of the energy
recovery system or when no energy is required for a long period.
On fixed speed compressors, run the unit unloaded for a few minutes before isolating the energy
recovery system from the compressor.
Stopping the unit for a long period
In case of an open water system and/or if freezing temperatures can be expected, isolate the
compressor water system and blow it through with compressed air.
Instruction book
2920 7101 24 107