This is the part of ownership that gets glossed over in the sales conversation. It is not expensive, but it is not optional either, and skipping it turns a good machine into a bad one.

Why filters are consumables, not parts

Every stage in a purification chain works by capturing something. Sediment filters fill with sediment. Carbon filters saturate with the compounds they adsorb. Membranes foul. UV lamps lose output over time even while still lighting up.

None of these fail loudly. There is no warning light on most units and no obvious change in how the machine behaves. A saturated carbon filter simply stops removing anything — and can begin releasing what it previously captured back into the water. That is why the replacement cycle matters more than it feels like it should.

What needs replacing, and roughly when

These are typical intervals under normal domestic use. Heavy use, dusty environments or poor-quality source water all shorten them.

What happens if you skip it

Not a dramatic failure. A slow, invisible decline, which is worse:

• Output drops first. A clogged air filter starves the machine of airflow, so it produces less water for the same electricity. Your cost per litre rises before anything else changes.
• Taste goes next. An exhausted carbon filter stops removing the compounds that cause off-flavours.
• Then the safety margin erodes. A fouled membrane and a weak UV lamp mean the barriers against bacteria are no longer doing what they were specified to do.
• Standing water is its own problem. Tanks need periodic sanitisation regardless of filter state, particularly if the machine has been unused for a while.

The uncomfortable version: a well-maintained unit produces excellent water, and a neglected one can produce water worse than the municipal supply it was bought to replace. The machine does not tell you which one you have.

Budgeting for it

Filter costs vary by unit and by which components fall due in a given year. The practical approach is to treat it as a fixed annual line item rather than a series of surprises, and to ask any supplier for a written schedule of what needs replacing when, with prices, before you buy. A supplier who cannot produce that list is telling you something.

Two ways to handle it. Buy filters yourself — cheaper in cash terms, but you have to track the intervals and source the right parts, and the failure mode is forgetting. Take a maintenance plan — a fixed monthly amount that covers the routine components and the scheduling, which trades a little money for the problem going away.

SkyTap Care costs R299 per machine per month and covers scheduled replacement of routine filtration components, reminders and scheduling, an annual inspection, annual cleaning and sanitisation, technical support, and better pricing on anything outside the plan. It is optional, you own the machine either way, and you can cancel with 30 days' notice. Whether it is worth it depends on how likely you are to actually keep up with the schedule yourself — be honest about that.

Habits that stretch the intervals

• Keep the intake clear. Do not push the unit tight against a wall or into a corner where it recirculates its own exhaust.
• Vacuum the air filter between changes. Gentle cleaning of the intake filter extends its life meaningfully in a dusty environment.
• Do not leave it idle with a full tank. If you are away, drain it. Standing water is where problems start.
• Use purification mode when humidity is low. Running the compressor hard for little water works everything harder for less return.
• Write the date on each filter when you fit it. Unglamorous, and the single most effective thing you can do.

Questions to ask before you buy any unit

These apply to any supplier, us included:

• What exactly needs replacing, and at what interval?
• What does a full set of replacements cost?
• Are filters proprietary, or standard sizes I could source elsewhere?
• How long will replacements be available for this model?
• Can I change them myself, or does it need a technician?

That last one matters more than it sounds. A machine that needs a call-out for every routine filter change has a much higher real running cost than its filter prices suggest.

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