Inline water filters are a simplified version of under-sink water filters and can be used for the filtration of water in low flow environments such as refrigerators, icemakers, water coolers, caravans or on a cold mains water line, or even as part of a reverse osmosis filter system. Compared to traditional under-sink water filters, inline water filters allow you to keep your existing kitchen tap, filtering all the cold water at the point of used it’s installed at.


Just like the filter media in any other filter cartridge, the filter media in inline water filters gets saturated with contaminants after prolonged use, and therefore, the filter needs to be replaced so it can efficiently remove contaminants again. Both the installation and replacement of an inline filter requires a little plumbing work, but it’s a task you can easily carry out yourself. In this article, we’re going to guide you step by step through the replacement process of an inline water filter.

First things first: getting the right filter, shutting off the water supply, and priming

Before you attempt to replace the filter, you need to make sure that you get the right type of filter, in the right size and model for the application you’re using it for. Next thing you want to do is turn off the water supply, then relieve the pressure if you’re using the inline filter with a water cooler or other similar application.

Filter cartridges are usually already primed, meaning that you can install them without any preparation. The packaging of the filter will specify whether your filter is already primed or whether you need to prime it yourself.

Identify flow direction

Inline water filters have two ends – the inlet and the outlet. The thicker end of the filter is usually the inlet, while the narrower end in the outlet. The filter usually has the flow direction marked on its side with an arrow.

Connect to tubing

Inline filters are usually connected with quick connect fittings, which make both installation and replacement very easy to carry out. Locate the collar and the little piece of tubing that is released by pushing down the collar. Slide the water filter tubing (or the tubing of whatever application you’re using it with) into the filter until it bottoms out, then pull gently effectively locking it in place. By pushing down the collar and slightly pushing in the tubing and then pulling it out, you’ll be able to remove the tubing again.

Some systems (e.g. reverse osmosis) may use threaded fittings, which you’ll have to unscrew on the old filter and reuse them on the new filter.

Turn on water supply and flush the filter

Once you’ve replaced the inline filter, turn on the water supply and check for leaks. If you’re using a carbon filter, flush the filter for around 10 minutes to remove carbon fines.

As you can see, replacing an inline filter is a fairly simple process, regardless of whether you’re replacing it on your water cooler or under-sink filter set-up. When you install a filter, or replace it with a new one, you should write the date on the filter with a marker so you can easily keep track of the filter replacement date. You can also make a note of the date in your calendar.