APPARATUS AND METHOD FOR CLEANING PIPES OF REFRIGERATING UNIT

摘要

An apparatus for cleaning pipes, wherein a four-way changeover valve (43) in a heat pump circuit (200) is switched to operate two transfer heat exchangers (25, 26) alternately as a cooler and heater, and to thereby circulate a cleaning refrigerant in a cleaning circuit (2) through a gas line (3) and a liquid line (5), a solenoid valve (SV3) being opened, when the amount of the cleaning refrigerant runs short during a cleaning operation by the circulation of the cleaning refrigerant, to replenish the refrigerant in a refrigerant cylinder (71) from a refrigerant makeup line (72) to either the transfer heat exchanger (25) or the transfer heat exchanger (26) which is in a cooling operation, a solenoid valve (SV4) being opened, when the cleaning refrigerant is excessive, to return the cleaning refrigerant from a refrigerant extraction line (73) to the refrigerant cylinder (71), whereby the amount of the cleaning refrigerant can be maintained at a suitable level.