Mira Excel Thermostatic Cartridge Assembly (903.33)

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• i am going to replace my old low pressure Mira cartridge after boiler upgrade does the Mira Excel/Select Thermostatic Cartridge Assembly 903.33 have Non-return valves integral to cartridge or will i have to fit check valves externally.
  thank you in advance if you can help
  best regards John

  Hello, the Excel does not have non return valves or need them, as the flow control is on the inlet side, therefore crossflow is not possible.

• We have a Mira excel mixer shower probably 20 plus years old. Over the last few years the shower pressure seems to have diminished slightly, have fitted new head and hose recently with no improvement to pressure. The hot and cold control is fine, would just like to improve the pressure slightly any suggestions ?
  Still gives a decent shower but we do not think it is as good as it used to be when first fitted, water supply and pressure is fine just wondered if it was due to age of the unit.

  Hello, it sounds like the inlet filters on the side of the 903.33 cartridge are getting a bit blocked up, remove the cartridge and flush the filters out.

• Hello. My Mira Excell approx 2005 is "screaming". Do I need a new cartridge and is this the correct one?

  Hello, it will be worth checking the inlet filters first, as screaming is usually a sign of an imbalance between the hot and cold flow into the shower.

• I cannot move the control from low to high pressure, the plate appears to be locked in position.

  Hello, the base plate can be VERY stiff, but brute force usually works, if you really can not move it, please return it and we will do it for you.

• I have a mira exel shower but am unsure of the age and type- it has 410.0c3 43/99 and Excel BIV written on a sticker - what type of cartridge would I replace the old one with ?

  Hello, an Excel of this age would need the 903.33 cartridge

• Our Mira excel shower continually drips hot water. Do we need to replace the complete thermostatic cartridge?

  Hello, yes if the shower drips, it will require a new cartridge.

• Hello
  I have a Mira shower that was installed in 1999 and I am looking to get a new cartridge for it, the original cartridge has the legend:
  410.01 25/99
  Excel EV WH/CHR

  Yes, the 903.33 is the correct cartridge for your shower.

• I have an old Mira excel Thermostatic Control shower unit. Recently I noticed the water is cold and I cannot seem to up the temperature. Can you pls advise. If I were to buy the replacement parts can I change it myself.
  Thank you.

  Hello,
  Yes, it sounds like the thermostatic cartridge needs replacing. This is quite easily done. There are two types of cartridges so if you have the older type this one 903.33 should be suitable.
  Thanks.

• I managed to lose one of the screws while changing the Mira Excel cartridge (I forgot to put the plug in the plughole!). Is it possible to get a spare screws?
  Thank you.

  Hello, they are part of part number 937.14

• Does the Mira Excel thermostatic cartridge assembly (903.33) come will all the seals needed or do these have to be purchased separately?

  Hello, it comes with all the necessary seals

• The cartridge on my shower has died (stiff & clicks & no water). Is the kit complete or do I also need to get seals, etc? Does it contain all the control knobs? The pic only shows the temperature limit ring. If not can I get them? Can I also get replacement chrome bezel and the plastic base it clips on to? If I have to replace the expensive bit I might as well freshen up the whole thing! Thanks.

  the part 903.33 is the internal cartridge for the shower and there are various different styles of control knobs/plates available. If you could forward a picture of your shower to support@showerspares.com they will be able to identify the one you have and send a link to the relevant site

• Hi. There is no cold water going into the shower. Took cartridge out and filters ok, put back in and all ok. Few hours later same problem, took out again put back in working then not working later, weird. Do I need a new cartridge, don't understand the intermittent working and not working.

  Hello, this sounds like you may have a partial air lock in the supply, ea time you remove the cartridge you are clearing it, but then it returns, you need to get a plumber in to fully flush the supply.

• My Mira excel shower was fitted around 16 years ago. The knob has been stiff to turn for a while and yesterday it clicked loudly and spence then no cold water has come out at all. Is this the cartridge? Don't want to spend all this kiney if not! Many thanks

  Hello, yes the stat has gone, it will need a new cartridge

• Hello
  Are the two seals for the back face of the Mira Excell 903.33 cartridge available separately?

  Hello, they are in the seal pack, part number 935.12 (the oval ones)

• The outer ring turns and clicks when I turn on the shower. Some times it works and others it doesn't.
  I've taken the white plastic covers off and tried to turn the black gear ring manually but again this is intermittent.
  Is the cartridge unit on its way out?
  Also, do you have to isolate the hot/cold water supply on the shower before replacing the cartridge?

  Hello, yes you do have to isolate the water, it does sound like the cartridge if faulty.

• Hi I have a Mira Excel shower installed in approx. 2000
  The temperature and flow rate have become a bit variable so I am guessing that a new cartridge is what is required.
  Can this be replaced from the front of the unit, ie the shower side or do I need to gain access to the back (which is currently sealed in!!)
  Thanks Steve

  Hello, everything is accessed from the front, you need to check the filters, first, if they are o.k, you will need a new cartridge.

• Hi Ive got a MIRA shower and before I buy a new catridge I wonder if you can help me understand if I really need one? The shower gets to the right temperature only if I have the outside slider all the way to the left in the red. Can I adjust this internally to make it more balanced or not??

  Hi your shower is set up in a normal way, you can however reset the point at which you get the hottest water, but this could allow other users to select a temp that would be too hot for them, but it is up to you how you set the maximum temperature

• My Mira Excel won't stop running!

  Hello, you will need to replace the Excel thermostatic cartridge, Mira part number 903.33, a seal kit alone will not cure this fault, the shut off seals are internal to the cartridge and not serviceable.

• My Mira Excel won't get hot. I've tested both hot and cold water pressure.

  Hello, Please check the inlet filters on the 903.33 cartridge, if they are clear then you will need to replace the cartridge 903.33.

• How do I stop my old Excel from dripping from the shower head?

  Hello, you will need to replace the Mira 903.33 cartridge to fix a dripping excel

• Will this fit my old excel that has a Green hub on the front?

  Hello, yes this cartridge is adjustable and will suit both the Green hub version High pressure 903.28 and the Yellow hub version Low pressure 903.27.