Filter cartridge, and method of retrofitting filter housing

A sealing valve for a removable filter cartridge, the sealing valve comprising:

• a first passage, a second passage, a third passage;
• first threads around a circumference of the sealing valve for removably coupling the sealing valve to a filter head;
• second threads threadable into third threads of a filter housing to couple the filter housing and the sealing valve;
• a first coupling nut with the first threads, the first coupling nut configured to be screwed onto the filter head while the sealing valve is not rotated to removably couple the sealing valve to the filter head;
• a circumferential groove;
• and
• a snap ring disposed in the circumferential groove, the snap ring configured to be compressed between the filter head and the first coupling nut when the first coupling nut is screwed onto the filter head,
• wherein the sealing valve is capable of being coupled to the filter housing to form the removable filter cartridge;
• the filter housing including a second coupling nut having the third threads and the second coupling nut being screwable onto the sealing valve to couple the sealing valve to the filter housing while the filter housing is not rotated;
• and
• the sealing valve, when coupled to the filter housing, has:
• (i) an open position wherein the first passage and second passage are configured to align with a first inlet and a second inlet of the filter housing, and the third passage is configured to align with an outlet of the filter housing;
• and
• (ii) a closed position wherein a sidewall of the first passage and a sidewall of the second passage are configured to block the first inlet and the second inlet of the filter housing, and a sidewall of the third passage is configured to block the outlet of the filter housing.

A removable filter cartridge comprising:

• a filter housing with an internal volume containing a filter;
• and
• a sealing valve coupled to an open end of the filter housing, the sealing valve including:
• first threads around a circumference of the sealing valve for removably coupling the removable filter cartridge to a filter head;
• second threads threadable into third threads of the filter housing to couple the filter housing and the sealing valve;
• wherein the filter housing includes a coupling nut with the third threads, the coupling nut being screwable onto the sealing valve to couple the sealing valve to the filter housing while the filter housing is not rotated;
• the sealing valve having:
• (i) an open position that allows fluid flow into and out of the internal volume of the filter housing, and
• (ii) a closed position that seals the internal volume of the filter housing, the sealing valve in the closed position configured to seal the internal volume while removably coupled to the filter head and maintain the seal while the removable filter cartridge remains uncoupled.

A sealing valve for a removable filter cartridge, the sealing valve comprising:

• first threads around a circumference of the sealing valve for removably coupling the sealing valve to a filter head;
• second threads threadable into third threads of a filter housing to couple the filter housing and the sealing valve;
• the filter housing including a coupling nut having the third threads and the coupling nut being screwable onto the sealing valve to couple the sealing valve to the filter housing while the filter housing is not rotated;
• wherein when the sealing valve is coupled to the filter housing, the sealing valve has:
• an open position configured to direct fluid from the filter head into the filter housing and then from the filter housing back to the filter head, and
• a closed position configured to seal the internal volume of the filter housing when the removable filter cartridge is removably coupled to the filter head and to maintain the seal while the removable filter cartridge remains uncoupled.