Main Eco Elite boiler fault

[bongos]

We have an 18 month old Main combi boiler and over the last few months the hot water has been intermittent when using the shower (mixer shower). Its getting progressively worse and now goes cold after being run for a couple of minutes then eventually warms up again before goung back cold.

Coincidentally we had the same problem on our previous boiler (a 4 year old Glow worm boiler) and ended up having to replace it with this Main one after five different engineers couldn't get it the hot water going again after an inital fix.

I can't believe its anything to do withthe mixer shower but don't want to replace this boiler now due to an intermittent fault as well!

Any ideas anyone?

 

[AGAS]

WTF 5 engineers couldn't get the boiler fixed for hot water ? to give an engineer a chance to solve this issue it has to be faulting at that time or he is taking an educated guess. hate intermittent faults

why don't you think its nothing to do with shower ?
and don't think another boiler is needed what is the flow rate like coming into your home ?

 

[bernardgreen]

Have a min max recording pressure gauge fitted to the water supply to the boiler. Odds on that the minimum recorded after the shower has been used and hot water failed will be less than the pressure the boiler needed to provide hot water.

 

[bazdaman]

You could run the shower and observe what the hall effect sensor led is doing, you will know if you are getting a good flow through the boiler or the sensors goosed, could even be a mucky plate does it only happen on the shower

 

[bongos]

Thanks for the suggestions guys. Yeah I should add - it wasn't a dig at the engineers. They were as frustrated as I was. One guy spent ages on it and did get it working for a few days but then it went again. By this point he said he could start replacing parts but it might just be wiser to get a new one as there was no gurantee the problem would reoccur.

So the mixer shower could be causing a problem then? I watched the hot water LED while the shower was being used and it seemed to be flashing then stopped for a bit. So is it possible that the flow is too low and so the boiler cuts off heating?

Just trying to get my head round it.

 

[bazdaman]

Can you turn preheat off by turning hw temp down on that model? If you can monitor the led then, i was talking about an led on the sensor you can see when the case is taken off that gives a clearer indication

 

[Agile]

You may need to clean the nozzle on the shower and turn the temperature knob on the boiler down a bit.

If that does not fix it then while using the shower turn a basin hot tap on at about half flow.

Tony

 

[bongos]

It is the model with the annoying preheat yes. Im not sure how to turn that off (doesnt seem possible on this model?). Im not sure we ever get much hot water from other taps in the house but I am impatient! Cold feed d/w does all the washing up and the pipe run for the combi is so long to the downstairs hot tap/kitchen tap we normally end up giving up before we get hot water/boil a kettle! Oh yeah but it does semm ok when run the kids their baths though this probably doesnt run as long as the shower does when it goes cold.

Ive turned the hot water setting downfrom 55 to about 45. Weirdly if i turn it down all the way it drops to 40 then jumps straight to 50 on its lowest setting.

I will see if this works if not then ill take the case off and look for this hall sensor thingy next time missus is running the shower.

Edit: just remembered something. Theres a small water save thingy in the shower hose that we fitted about 6 months ago. The problem didn't appear at the time but i guess it could be linked with what you say about not enough pressure registereing at the boiler when using the shower?

 

[dilalio]

I would be looking very closely at the shower! Take the damn water saver off it for a start - no point saving water you aren't getting

How old is the shower? Cartridges go all the time on them (especially in hard water areas) are you able to T into the shower feeds somewhere and bypass the valve to check if that's where the issue lies?

 

[Agile]

Wow, you have a flow problem and want to make it worse by restricting the flow even more!

Just been talking to landlord friend who has Triton showers and their cartridges can fail as often as every two/three months!

 

[AGAS]

triton are shyte

 

[Agile]

They apparently come with a five year warranty and send an engineer out to replace the cartridge.

I cannot see how they can finance that on a single purchase!

 

[bongos]

The water saver was put on several months ago - prior to any problems. It off now, worry ye not. When i last used the shower (after turning down the boiler hot water) it didnt go cold. Ive only used it once since then though so will see what happens tomorrow.

The mixer shower is a Bristan. Never heard of them so im guessing theyre also shyte. It was put by the plumbers when we had the bathroom done about 2 and a half years ago now. Though the shower doesnt really get heavy use as only me and the missus use it.

 

[bongos]

Ok so an update. Ive turned the hw temp down, cleaned the shower head thoroughly (we live in a very hard water area) and had also removed the water saver thingy.

At the moment all is good and there have been no further problems. Many thanks for the advice.

One final question - does anyone know how (or even if) i can switch off preheat on this model of boiler? (Main Eco Elite)

 

[bazdaman]

It tells you on the drop down flap? Turn hw temp all way down and leave between 12.00oclock 12.05