Fluid conditioning systems having caps with filter cartridge sealing and removal devices and/or locking devices

A fluid conditioning unit comprising:

• a housing having an axis;
• a cap threadably secured to and unsecured from the housing by rotation about the axis, the cap forming a removable seal with the housing when secured thereto;
• a cartridge device secured to the cap in a manner that restricts movement of the cartridge device with respect to the cap along the axis but allows rotation of the cartridge device with respect to the cap about the axis;
• a filter cartridge removably secured to the cartridge device, the filter cartridge being disposed in the housing along the axis;
• a first seal for removably sealing the cartridge device and an inner surface of the housing;
• and
• a second seal for removably sealing the cartridge device and the filter cartridge.

A fluid conditioning unit, comprising:

• a housing having an axis;
• a cap threadably secured to and unsecured from the housing by rotation about the axis, the cap forming a removable seal with the housing when secured thereto;
• a cartridge device secured to the cap in a manner that restricts movement of the cartridge device with respect to the cap along the axis but allows rotation of the cartridge device with respect to the cap about the axis;
• a filter cartridge removably secured to the cartridge device, the filter cartridge being disposed in the housing along the axis;
• and
• a locking device that locks the cap to the housing once the cap is threadably secured to the housing.

A fluid conditioning unit, comprising:

• a housing having a first thread and a locking feature;
• and
• a cap having a second thread, a handle and a locking arm, the first and second threads being selectively engagable and disengageable from one another,
• the locking arm being movable between a locked position and an unlocked position, the locking arm, when in the locked position, being receivable in the locking feature to prevent unthreading of the cap from the housing, and the locking arm, when in the unlocked position, being free from the locking feature to allow unthreading of the cap from the housing,
• the handle being movable, with respect to the cap during threading and unthreading of the cap from the housing, between a first position and a second position, the first position corresponding to the locked position of the locking arm and the second position corresponding to the unlocked position of the locking arm so that when a user applies an unthreading force to the handle, the handle moves to the second position and moves the arm to the unlocked position and so that when a user applies a threading force to the handle, the handle moves to the first position and moves the arm to the locked position.