Apparatus to clear oil from the hoses and front end of a recovery recharge machine
A refrigerant recovery unit is provided that can recover and recharge refrigerant. The unit is further configured with a pair of service hoses and a refrigerant control circuit operable to receive and transport the refrigerant between the hoses and the storage vessel and to process the refrigerant to substantially remove contaminants from the refrigerant. A fluid connector is provided in fluid communication with the hoses to enable the refrigerant to flow between the hoses and to establish a closed loop through the refrigerant control circuit, and a controller is operatively connected to the refrigerant control circuit and configured to control a flow of the refrigerant through the refrigerant control circuit and through the fluid connector.
1. A method of removing contaminants from a refrigeration recovery unit comprising the steps of:
connecting a first end of a high side service hose and a first end of a low side service hose to a first portion of the unit that provides a refrigerant to the service hoses;
connecting a second end of the high side service hose and a second end of the low service hose to a second portion of the unit so that the second ends form a closed loop;
charging the low side service hose with the refrigerant, wherein the refrigerant flows into the high side service hose;
recovering refrigerant from the high side service hose while continuing to charge the low side service hose;
charging the high side service hose with refrigerant while recovering refrigerant from the low side service hose;
stopping the charging of the service hoses; and
recovering refrigerant from the high and low side service hoses until a measured pressure reaches 0 psig.
2. The method according to claim 1 further comprising continuing to recover for an additional 30 seconds after the pressure reaches 0 psig.
3. The method according to claim 1 , wherein the charging, recovering and stopping steps are performed automatically.
4. The method according to claim 1 wherein the connecting step further comprises using a coupler to connect the first ends and the second ends.
5. The method according to claim 1 further comprising separating an oil from the recovered refrigerant into an oil container of the refrigerant recovery unit.
6. The method according to claim 1 further comprising opening valves at the second ends of the hoses to allow the refrigerant to flow there through.
7. The method according to claim 1 , wherein the recovering of refrigerant is done with a vacuum pump.
8. A method to flush a contaminant from service hoses of a refrigerant recovery unit, comprising the steps of:
connecting a first end of a high side service hose and a first end of a low side service hose to a first portion of the unit that provides a refrigerant to the service hoses;
connecting a second end of the high side service hose and a second end of the low service hose to a second portion of the unit so that the second ends form a closed loop;
entering a predetermined amount of time for flushing the service hoses;
measuring a pressure within the service hoses with a pressure sensor;
performing a recovery of refrigerant if there is a positive pressure in the service hoses;
determining if there is an adequate vacuum in the service hoses after the recovery;
performing an evacuation of the service hoses if the vacuum is inadequate;
flushing the service hoses with a refrigerant for a predetermined period of time; and
recovering refrigerant from the service hoses.
9. The method according to claim 8 further comprising monitoring a refrigerant flow during flushing.
10. The method according to claim 9 , wherein if the flow is below a predetermined level of flow, the flushing step is stopped.
11. The method according to claim 8 , wherein the flushing step further comprises circulating refrigerant in one direction of the closed loop and circulating refrigerant in a second direction of the closed loop.
12. The method according to claim 11 , wherein the refrigerant flows in the first direction for approximately a minute and a half, and flows in a second direction for approximately another minute and a half.