Frequently Asked Questions

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Shower Mixing Valves & Kits

Will my new FM Mattsson shower & taps work on my low pressure system?

FM Mattsson units are designed to perform at their optimum at between 0.5 - 6.0 bar. We do not recommend FM Mattson units be fitted to systems with pressure below 0.5 bar

What do I use to clean my FM Mattsson units?

Units are best cleaned using a soft cloth with mild detergent. Under no circumstances should acids in any form be used or any abrasive cloths or cleaners as this will damage the unit.

There is no water coming out of my shower mixer?

First check that there is no interruption to water supply either hot or cold. If you do have supply to the unit the problem is likely to be due to debris coming down the line existing pipework and blocking the supply inlets to the unit. FM Mattsson units are fitted with strainers to avoid internal contamination of the units by debris. Turn off the water supply remove the unit from the wall fixing plate and clean the wire strainers inside the fixing nuts then reattach.

Water temperature from my FM Mattsson mixer is fluctuating alternately between hot and cold?

This may be due to the unit being fitted incorrectly. Check that the cold supply is on the right and hot supply is on the left.

The water out of my mixer is not hot enough?

Firstly check that you have sufficient hot water supply. Secondly check that you have depressed the childproof anti scald device on the temperature control (right hand side of mixer) to enable you to increase the temp beyond 38?. If you have done this and reached to full extent of adjustment you may need to recalibrate the unit to suit your own specific requirements (See Re Calibration in Manual)

The Control handles on my mixer are getting stiff?

First check that no materials have fallen between the handle and mixer body that may prevent free movement. If no obstruction is found then the most common cause is the build up of scouring powder/paste debris within the control handles.  FM Mattsson units should not be cleaned with scouring powders, pastes or acid solutions as debris will build up between the handles and body of the mixer and over time will erode the control surfaces and ultimatly damage the cartridge . Units should only be cleaned with a mild detergant and diluted limescale remover when required.

To rectify problem remove handle and extract debris and replace. In cases where significant damage has been caused, handle and cartridge may need to be replaced.

Water Saving Showerheads

  How easy is it to fit the showerhead?

  Simply unscrew your existing showerhead and remove from the shower hose, then screw the new showerhead on the shower hose. The ½ inch shower hose is standard on all UK showers and will fit all showerheads

I have hard water; will my showerhead be affected?

The Challis water saving showerhead helps to reduce scaling because of the technology used to propel and aerate the water flowing through the showerhead

What are the maintenance requirements?

None, only the occasional wipe when cleaning your shower is required to keep your showerhead looking like new.

What are the minimum water pressure requirements?

The Challis showerhead is designed to work on low pressures and will provide good showering performance at pressures down to 0.8 bars.

Does the showerhead use a restrictor valve?

No, unlike other low-flow showerheads that simply restrict flow, the showerhead utilises the principles of fluid mechanics to accelerate and pressurise the water flow to give a truly high performance showering experience.

How much will my water and energy bills be reduced by?

Much depends on the flow rate from your existing showerhead and how long you spend in shower.  It is common to see both the water use in the shower and energy costs to heat that water be reduced by over 70% when you fit the

What is the guarantee on my showerhead?

The Challis showerhead is factory tested and made from the highest quality materials. They will meet the demands of constant use and maintain their pristine condition. Each showerhead is guaranteed for 12 months and if there is a problem with the product within the guarantee period we will replace the showerhead without quibble.


Will it work with my shower?

The  Challis showerhead will work on any shower with greater than 0.8 bar pressure ( the average UK shower in the home should be greater than 1 or more bar of pressure). The shower works effectively on pumped systems (power showers) and direct fed combi boilers. It can be used on electric showers to improve showering performance but there may not be a significant saving benefit.  It is not designed to work effectively with low pressure gravity fed systems ( this is from a water tank in the loft)

As I am sure you will notice this section is very short. This is due to the fact that as a result of the technical excellence of FM Mattsson units we very seldom have any problems. If however you experience a problem that we have not covered please contact us.


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