Newbie needs help upgrading a shower

[Meeten]

Had a look through the forum and couldn't find the answer to my Q, so thought I'd ask here.

We have a Triton Jade shower at the moment and the force from it has been reducing to the point where it is a little more than a dribble.

I've descaled the head, and this made a marginal improvement, but am now thinking of replacing the whole unit. Looking for suggestions - should I attempt anything else before changing the unit? Is there anyway to see which unit would be a better replacement?

I can't see the power (think it is 8.5kW), and the main switch (outside the bathroom) is sealed, so I can't see the fuse rating.

Thanks

 

[jj4091]

Is there an in-line filter in the water inlet pipe? If so clean that out also. Unless you are changing like for like, replacing a shower unit may not be that simple.

 

[ban-all-sheds]

I can't see the power (think it is 8.5kW), and the main switch (outside the bathroom) is sealed, so I can't see the fuse rating.

The fuse/MCB won't be in the isolation switch, it will be in the consumer unit.

And it has nothing to do with how well the shower works anyway.

How long have you had it, or been on the property? Is this your first experience of it in winter?

 

[philiprreeves]

I would have to agree with the above thread.

Most electric showers are very poor when it comes to output of hot heated water. The shower is a glorified kettle if you like. It heats the water up asyou use it and there for the hot you want the water the less water output you will get. This why people tend t buy 10, 10.5,11 or even 11.5 KW showers to conbat this problem.

It won't be the electrics if there is hot water at the shower already. It will be the heating eliment and flow meter. Nor worth replacing cheaper to buy new and bigger shower.

If you go bigger make sure the cable is 10mm twin and earth and you may have to upgrade the fuse at you consumer unit (CU) to 40/45A.

If you have a conbi boiler, get rid of elec shower!!! Have a combi mixer far better and very powerfull if your hot water flow is high. The other type would be a power shower which works of a hot/cold pump fitted either under the bath or in the loft above the shower unit. These work on your normal boiler and provide a very powerfull spray of hot water as long as your water heating has been on.

Thanks, Phil

 

[ban-all-sheds]

The shower is a glorified kettle if you like.

Nah - you're thinking of the over-sink instant water heaters....

 

[StevenJ]

I've seen a few threads like this over the least few days, all the talk about 6mm and 10mm cable to 32/40amp fuses etc. Now I know nothing about electrics but it got me wondering what my supply was as we got someone to take out our old 7kW Triton T80 for a new 8.5kW T80si just over 3 months ago. Anyway, it looks like we have the 6mm cable on a 32amp fuse and the shower has worked flawlessly, never had any trips or blown fuses.

Now like I said, it has worked with no obvious problems, but it has got me a bit anxious and I'm wondering whether I should have my cable and fuse upgraded, because I keep reading that most people recommend 10mm cable and 40amp on anything rated 8.5kW and above??!

 

[Spark123]

A 8.5kw shower, assuming it is 8.5kw @ 240v requires a 35.4A supply. This means that it should not be fitted to a protective device less than 35A, the next common size up is 40A. The current carrying capacity of the cable as installed then needs to be not less than 40A.
You can't say 6mm cable is rated at x Amps as the rating depends on the method of installation, wether it is in contact with any thermal insulation, wether it is grouped with any other circuits, ambient temperature and how long the cable run is.
In a nutshell - they should not have installed the larger shower.

 

[Cremeegg]

It may just be that the sparks did his calculations and 6mm could be enough for the larger shower. A 32A fuse/MCB will take 35A for ever - so you may be OK. On the other hand get a proper registered sparks to check it out and remedy any defects. Is it RCD protected?

 

[ban-all-sheds]

A 32A fuse/MCB will take 35A for ever

Ib <= In <= Iz

I wonder if he falsified an EIC?

 

[Cremeegg]

I wonder if he gave them an EIC at all? Maybe he thought it should be a MWC?

Perhaps, just perhaps, it might all be kosher but having come across several iffy shower replacements I doubt it. One last week up from 6.5kW to 9.5 kW still on 6mm2 cable; customer fed up with replacing 30A fuse - tried to get 45A one instead but found that it didnt fit. I explained that it didnt fit for a reason!. New cable; RCD for the first time!; and new supply off Henleys next week.

 

[ban-all-sheds]

I wonder if he gave them an EIC at all? Maybe he thought it should be a MWC?

It would be - sorry - I was thinking this was a new circuit.

Perhaps, just perhaps, it might all be kosher

Don't see how it can be - even if the cable is OK for the load, and is OK for the protective device, and even if the OPD never trips in practice, if Ib > In it won't comply...

 

[Cremeegg]

Agreed - good job I'm not Jewish.

 

[StevenJ]

I was looking through my Triton T80si installation manual last night (yes I got bored) and there is a table of recommended minimum and maximum ampages for 6mm and 10mm T&E. According to it, 6mm T&E cable, clipped onto a wall or through a cavity wall that is uninsulated can carry upto 45A. The minimum if the cable is plastered into a wall is 32A.

 

[Cremeegg]

Looks like Triton need to read BS7671:2008 Table 4D5 that gives ratings for flat twin and earth with a new range of possible installation methods compared to BS7671:2004.

6mm clipped direct to wall is 47A; but can be as low as 23.5A when in insulation.

10mm clipped direct is 64A.

 

[nozspark]

I had one like this a couple of weeks ago, customer got a free replacement from the manufacturer but after replacement it was exactly the same. After a short time I had a look at the hose (new shower unit didn't come with one) and found that the internal plastic lining had collapsed and was blocking th flow of water!!

P.S. New shower came as a bare unit (i.e. no accesories)