Mira 416.41

A: Oops! just noticed that this has been answered twice!

A: 

 

You have probably read this before however.....

I think a micro switch is stuck in the on position, this is keeping one of the elements energised after you have switched off the shower will keep heating and perhaps boil off some of the water inside, until the Thermal Cur Out (TCO) cuts the power off to the elements, when the shower cools down the TCO will allow the power back to the elements and the whole process starts again.

You will have to trace which switch is causing the problem and replace it. (On some showers the switch is part of a sub assembly therefore the complete assembly will need replaced)

Until you get the switch replaced switch the shower on and off using the isolator switch (pull cord)

 

TCO’s in general very seldom fail unless the shower has been overheating and if a new one is faulty it basically just doesn’t work from the word go.

 

I have checked back and we have had no faulty returns for this part since the beginning of the year.

 

 

A: You would need to test if there is still power getting across the TCO when the shower is  switched off. If so then you may have a faulty micro switch, if thisis the case replace the faulty switch or relay and make sure that you switch theshower off at the isolating switch when the shower is not in use because thismay cause the new TCO to fail.
Alos when fitting a new TCO make sure you do not press the bottom.

A: 

The things to check first are:

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water getting to your shower to cool it properly the overheat safety device will turn the power off until it cools Then it all starts again

 

Make sure that the shower head is clean and clear, that the hose isn’t kinked (this can happen just behind the hand set where it is difficult to see) also check the inside of the hose although it can look OK on the outside it could have collapsed internally

The other possibility is a faulty flow/stabilizer valve not allowing the correct amount of water into the shower.

A rough check is to remove the shower head turn temperature control to fully hot the water coming out of the hose should be a bit more than a dribble then turn to fully cold and it should be coming out at full flow.

If there is not much difference between the two then you could have a faulty flow valve.

Carry out this check after you check the inlet valves.

A: http://www.google.co.uk/#hl=en&safe=off&sclient=psy-ab&q=verdigris&oq=verdigea&gs_l=hp.1.2.0i13l2j0i13i10l2.1858.9030.0.16801.8.8.0.0.0.0.114.673.7j1.8.0.les%3B..0.0...1c.1.5.psy-ab.C3xtpqWb2jU&pbx=1&bav=on.2,or.r_qf.&bvm=bv.43287494,d.d2k&fp=64a5155518d1f2bb&biw=1280&bih=968

This is a common problem in some areas and once cleaned off it should not affect the TCO.

A: 

The things to check first are.

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water
getting to your shower to open / close the safety device that allows power through to the elements

Make sure that the shower head is clean and clear.

If all the above is OK then contact Mira this shower has a 2 year guarantee if you start to fiddle with it, it may invalidate your guarantee.

http://www.mirashowers.co.uk/onlinecatalog/detail.htm?productNumber=1.0.419.32.1&section=Electric

 

 

A: Depending on the shower, it is sometimes easy to remove the TCO without removing anything else or turning the water off.

A: 

The things to check first are:

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water getting to your shower.

Make sure that the shower head is clean and clear, that the hose isn’t kinked (this can happen just behind the hand set where it is difficult to see) also check the inside of the hose although it can look OK on the outside it could have collapsed internally

The other possibility is a faulty flow/stabilizer valve not allowing the correct amount of water into the shower.

A rough check is to remove the shower head turn temperature control to fully hot the water coming out of the hose should be a bit more than a dribble then turn to fully cold and it should be coming out at full flow.

If there is not much difference between the two then you could have a faulty flow valve.

Carry out this check after you check the inlet valves.

A: There are no liquid parts in a TCO. If you have liquid "coming out" of or near the TCO then it is coming from somewhere else. Check that there is no water getting into the shower especially from the top screw holes.

 The most common cause is a switch sticking in the on position.....See below

After fitting a new TCO

When fitting a new TCO listen to the shower, after it has completed its first on/off cycle, if when it is switched off you hear it continuing to heat (Noise like a kettle starting to boil) this will mean that there is a switch or a relay that is stuck in the on position, this is keeping an element energised and this is probably what caused the original TCO to fail.

If this is the case replace the faulty switch or relay and make sure that you switch the shower off at the isolating switch when the shower is not in use because this may cause the new TCO to fail.

A: 

I would just use Jif or something, however it normally isn’t anything to worry about, it is usually caused by the flux residue when the heater elements are brazed into the top of the tank.

A: No. Electric showers such as this one usually run of the mains water feed.

A: 

Sometimes they just fail!

 

However the most common cause is a switch sticking in the onposition.....See below

 

 

After fitting a new TCO

 

When fitting a new TCO listen to the shower, after it hascompleted its first on/off cycle, if when it is switched off you hear itcontinuing to heat (Noise like a kettle starting to boil) this will mean thatthere is a switch or a relay that is stuck in the on position, this is keepingan element energised and this is probably what caused the original TCO to fail.

If this is the case replace the faulty switch or relay andmake sure that you switch the shower off at the isolating switch when theshower is not in use because this may cause the new TCO to fail.

 

 

 

A: 

They may be connected to the on / off switch, however you don’t mention which model of Sport you have, so I can’t be sure.

Also unfortunately we do not have wiring diagrams for showers, perhaps the best place to go for a wiring diagram would be direct to Mira  

A: 

 It may be a faultyelement in the heating tank (there are two, three in most 10kw showers) you cancheck them with a multi meter you should have a reading of around 12>18ohms.

If you have power to the elementsand no heat it's probably the elements, no power to the elements thenit's probably a micro switch.

 

If you don’t have amultimeter  we sell them at £10 each with a guide on how to use them forchecking and testing the various parts of your shower.

 

Apart from helping to fix yourshower, they are really useful for checking you have a power supply toappliances, for checking fuses, letting you know much power you have left inbatteries

(so you know if they are dud ornot)  and lots of other jobs, in short they are well  worth the £10.

 

http://www.showerdoc.com/installation/electrical-products/SKYTRO-600-005-Digital-Multi-Tester

 

A: 

A: Forgetting about the temperature turn the shower from fully hot to fully cold at fully hot you should have not much more than a dribble coming from the hose and on fully cold you should have a good strong flow, if you do not have this difference then you may have a faulty flow/stabilizer valve

A: Depending on the age of the shower, the problem is either the Pilot valve -post 1999 or the flow valve -post 2000. You can test this,

Forgetting about the temperature turn the shower from fully hot to fully cold at fully hot you should have not much more than a dribble coming from the hose and on fully cold you should have a good strong flow, if you do not have this difference then you may have a faulty flow/stabilizer valve.

A: 

Weare having a problem at the moment with our ticketing system it is runningwords together, we have people working on it!!

 

Iam afraid you can’t reset the thermal switch it needs to be replaced.

A: 

If the shower is absolutely cold then I thinkyou may have a faulty Thermal Cut Out

A faulty TCO will have no continuity across the two terminals(The black thing on top of the heating tank)

Therefore a good TCO will have power at both connections and afaulty TCO will have power at only one.

(The function of the TCO is, if the water over heats it cuts thepower off to the elements)

See Video.

http://www.youtube.com/user/showerdoc#p/u/2/_zi8JbEMYMs

 

Ifthere is some heat it may be a faulty element in the heating tank (there aretwo, three in most 10kw showers) you can check them with a multi meter youshould have a reading of around 12>18 ohms.

If you have power to theelements and no heat it's probably the elements, no power to theelements then it's probably a micro switch.

 

If you don’t have a multimeter we sell them at £10 each with a guide on how to use them for checking andtesting the various parts of your shower.

 

Apart from helping to fix yourshower, they are really useful for checking you have a power supply toappliances, for checking fuses, letting you know much power you have left inbatteries

(so you know if they are dud ornot)  and lots of other jobs, in short they are well  worth the £10.

 

http://www.showerdoc.com/installation/electrical-products/SKYTRO-600-005-Digital-Multi-Tester

 

A: 

The things to check first are.

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water
getting to your shower to open / close the safety device that allowspower through to the elements

You don’t mention which showeryou have however the other possibility is a faulty pilot or flow valve

A: 

If when the shower was switched off did you hear itcontinuing to heat (Noise like a kettle starting to boil) this will mean thatthere is a switch or a relay that is stuck in the on position, this is keepingan element energised and this is probably what caused the original and the new TCOto fail.

 

It would unusual for a new TCO to fail for no reason.

If you heard no noises coming from the shower then we will replacethe TCO, however we will test the original TCO when it is returned.

If you do wish to return it please send me your invoicenumber and contact details to gt(at)showerdoc.co.uk

A: 

Issue = no H/W;flowLEDoff; ~13.4ohms on 2 back Neutral posts to each of 2 front posts of tank.(Assume this OK?)

Sounds OK

 

How test 2 microswitches(872.01,28) ?

 

Check for continuity, push button in continuity let button gono continuity

 

Or how test flow

Rough check turn flow up and downthe flow should modulate.

and switch assemblies(1563.507,509) ?

See 1 Above

(3) Continuity oninstalled TCO gives none.

= TCO faulty

Take TCO off and now saysok!

Can’t explain that! Unless it has something to do withthe “paste”

Being confused I look topof tank where TCO sits and 3/4mm dia blob of white grainy paste. I thoughtthermal conductive paste (like on PC cpu to heatsink).

No thermal transfer paste used onthis unit, more likely to be residual flux that wasn’t cleaned away.

Then notice on undersideof TCO the disc pushes into TCO body.

This is correct

Pushed in and loosecontinuity and at rest gain continuity.

Pushing the bi-metallic disc inis the best way to damage a TCO!

 

 I surmise that paste is some sort of buildup?I'll just clean TCO and tank top and reassemble.

Definitely worth a try

(4) But... HOW does heatfrom tank top cause this disc to move upwards into TCO causing loss ofcontinuity/power cut off?

I was expecting sort of bi-metallic sort of heat sensing setup...

The Disc is Bi-metallic

A: 

You don’t mention which model of Sport you have, However......

 

 The things to check first are.

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water
getting to your shower to cool it properly the overheat safety device will turn
the power off until it cools Then it all starts again

Make sure that the shower head is clean and clear, that the hose isn’t kinked (this can happen just behind the hand set where it is difficult to see) also check the inside of the hose although it can look OK on the outside it could have collapsed internally

If all of these are OK then you are going to need a new pilot valve if you have the older model and a new flow valve if you have the newer Sport

A: 

Sorry we don’t have wiring diagrams for this shower you could try Mira directly  http://www.mirashowers.co.uk/home.htm or if you send us a few photos we may be able to work out what goes where.

A: 

Here is how to check the Thermal Switch/Thermal Cut Out

A faulty TCO will have no continuity across the two terminals (The black thing on top of the heating tank)

Therefore a good TCO will have power at both connections and a faulty TCO will have power at only one.

(The function of the TCO is, if the water over heats it cuts the power off to the elements)

See Video.

http://www.youtube.com/user/showerdoc#p/u/2/_zi8JbEMYMs

 

A: Sounds as though the thermal switch is operating correctly and the problem is not enough flow through heating can.
Check that hose is not kinked or collapsed internally and then shower head is clear.
Check that mains stopcock and any isolation valve in the feed to the shower are fully open.
Check that inlet filter is clear.
If all above are ok the it is either the pilot or flow valve at fault depending on which model of Sport you have.
If you click on the link below it will take you to our Mira page and you can identify your model and order the part required online.##

http://www.showerdoc.com/shower-spares/mira

A: As long as it is post1998, if an earlier model then you need part no 872.30.

Alastair