1. The definition of non-condensable air

In the application of LiBr absorption chiller, LiBr absorption heat pump and vacuum boiler, non-condensable air indicates the air which can’t condense and can’t be absorbed by LiBr solution. For example, the air enters LiBr absorption units from the outside and hydrogen generated from corrosion inside units.

2. The source of non-condensable air

Leakage or improper operation

Since LiBr absorption units are working under high vacuum condition, the air can enter the unit easily when there are leakage points or damage of the shell and heat exchanger tubes. Even if the unit is well made, it’s also difficult to ensure the air tightness of the unit after long time operation.

Hydrogen generated by the internal corrosion

LiBr absorption units is mainly composed of steel or copper, the corrosion reaction of LiBr solution to metal is mainly carried out by the electrochemical, under the effect of oxygen, metals are oxidized in the LiBr solution which losses of 2 or 3 electrons and then produces hydroxides, such as Cu(OH)2. The electrons combine with the hydrogen ion H+ in the LiBr solution to produce the non-condensable air - hydrogen (H2).

3. How to deal with the non-condensable air？

The LiBr absorption chiller and LiBr absorption heat pump of Hope Deepblue not only are equipped with vacuum pump, but also be standard designed a corresponding air chamber to store the non-condensable air which is generated during the operation. Some additional devices and functions, like solenoid vacuum valve and automatic start/stop vacuum function, are optional for customer’s demand, which can greatly reduce the manual intervention times for purging and save cost.