Quincy QSV 2200, Instruction Manual

Page: 73 / 124

Section V - Options
Quincy Vacuum Pump-QSV Series 73
As soon as the oil temperature reaches the set point (condensation temperature), the valve starts closing off
the bypass over the oil cooling system, gradually allowing the oil to flow through the heat exchanger (HE).
As the oil temperature rises to the approx. condensation temperature, all the oil passes through the heat
exchanger cooling system. The exchange of heat between the vacuum pump oil and the heat recovery water
is maximum. The oil from the heat exchanger outlet flows via oil filter (OF), vacuum pump element (E) and
separator (OT) back to the inlet of heat exchanger (HE). The electronic thermostatic valve (BV) the main 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, the thermostatic valve will gradually allow the oil to be cooled in the oil cooler (Co).

Recovery water flow too high/temperature too low
In this case, the thermostatic valve will open the bypass line allowing oil from heat exchanger (HE) to be
mixed with oil from separator (OT).
Energy is transferred from the vacuum pump oil to the water, but at a relatively low temperature level.
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.
Stopping the unit for a long period
In case of an open water system and/or if freezing temperatures can be expected, isolate the vacuum pump
water system and blow it through with compressed air.
5.4 Maintenance
Vacuum pump oil
For references used consult section Energy recovery unit.
Oil change:
1. Run the unit until warm. Stop the unit, switch off the isolating switch and close the air outlet valve of the
vacuum pump.
2. Depressurize the vacuum pump and drain the oil by opening the drain valve. Also drain the oil from the heat
exchanger by opening the drain plug on the heat exchanger (HE). Close the plug after draining.
3. Resume oil change as described in section Oil and Filter Change in this book.
Heat exchanger (HE)
If the temperature rise over the energy recovery system declines over a period of time with the same basic
working conditions, the heat exchanger should be inspected. To clean the oil side, soak the heat exchanger
in a degreasing solution. To remove scale formation in the water compartment, a proper descaling process
should be applied. Consult Quincy.