Auto-Purger Plus (APP)

It is nearly impossible to predict where noncondensible gases (air) will accumulate. Therefore, purging at several points on the high-pressure side of the system is the best method for removing air from the system. For multipoint purgers, the solenoid valves may be manifolded into one line to the purger. However, only one purge point should be purged at a time. Connecting two purge points together may result in gas flowing from one condenser to another due to unequal pressure drop, even though the difference in pressure drops is very small, for example ¼ psi (0.02 bar). The result is that even in the best of circumstances, only one point is effectively purged. The best practice is to purge each condenser and receiver circuit separately.

It is extremely important to install purge points at locations sure to be liquid free. Also, no liquid traps are desirable either before or after purge point solenoid valves. The line from the purge point on the condenser to the AUTO-PURGER Plus should not pass through cold areas where further condensing of the saturated gas can occur. If this cannot be avoided, the purge line must be insulated because flooded purge point lines will flood the AUTO-PURGER Plus with liquid, resulting in a temporary halt of noncondensibles being removed.