Ravenstar LS 100T Intermittent hot water

[Grantyy]

Hi

I know these boilers aren't great but I had a good run with mine, until now that is.
When the hot tap or shower is on the boiler kicks in, often later than the 3 seconds stated in the handbook, it runs for 30-60 secs and then cuts out, it can then be about another 30-60 secs before it tries again and does the same?

I'd guess its an overheat protection but then sometimes it doesn't even get so hot before it trips out again.

There are two points that may be worth noting and the first is that the boiler has always lost pressure, The plumbers who fitted it actually left the flexi pipe attached and told me how to repressurise it though I now know he shouldn't really have done so. It used to lose pressure every 4 days to 2 weeks but then stabilised for a while but now its losing pressure every few days though I have never seen any leaks.
There was an issue with a pressure valve leaking the same day Anglian Water fitted my water meter, I don't remember if it was just called a pressure valve but its located inside the main chamber on top of an upright pipe on the right hand side of this model. When we fit the part it was a pain as we had two wrenches and it wanted to come loose in a third place. I have checked the area below the valve and there is no sign of a leak
The other issue is that there is a loose wire within the main electrics box, it just takes a slight knock on the front near the power switch and it will power down although I dont see that being the issue as the CH works fine

One further thing I have noticed is that there is often a fluctuation in the water pressure, the kitchen tap has always seemed under powered to me but lately I have noticed and the same with the shower that the flow does vary, it noticeably slows and quickens at times although I don't know if that could be an issue

If you guys have any constructive ideas as to what the problem is then I thank you in advance.

 

[Agile]

Better to thank us when you read the answer by clicking the thanks button!

Its likely that constantly repressurising has caused dirt in your system and the plate heat exchanger is blocked.

This can be diagnosed by measuring the flow and return temps during hot water delivery. You can see the FAQ and search for further information.

It seems you expect to buy a cheap boiler and never to get it professional serviced or problems fixed.

The leaking should have been sorted out as soon as you became aware of it.

Tony

 

[Grantyy]

Thanks Tony I'll look into that.

When you say the leaking should have been fixed do you mean the leak from the handle on the flexi pipe? it only happens for about 2-3 secs whilst adding pressure, the leak on the valve was fixed same day!

Regarding servicing it was not something I was aware was needed tbh, I don't know a single person who has serviced there boiler and I know a lot of people who have them,If I understood the importance of this then I would certainly pay for the service.

Does anybody else agree this is the likeliest solution or have any other suggestions

 

[oilhead]

The problem you have is that many of the 'engineers' you are likely to get don't know how combis work and will just change parts. What you say about the valve taking 3 seconds to switch suggests that the diaphragm is worn or split, or maybe the flow switch is worn, sometimes making sometimes not. The flow switch is easy to replace as it just pushes over the neck of the diverter valve and it is also cheap. For the need to remove the diverter valve to replace the diaphragm, it may be worth changing that complete with a re con job off Ebay.
Lots of engineers will often suggest a boiler change rather than apply themselves to a repair. It speaks volumes when a new boiler is left with a significant system pressure drop from day one, about the quality of their skills.

 

[Agile]

The leak which should have been fixed is the losing pressure every few days!

Tony

 

[Grantyy]

That's the problem Agile I had two plumbers out to question why the pressure is dropping and none had any idea, one told me that the flexi pipe should not have been left in place and suggested there was likely a leak somewhere yet in 4-5 years I have seen no constant leak, I even had floorboards up upstairs but surely over that amount of time there would be visible signs if there was a leak.
I guess one thing I have learned regarding boilers is to not just call a plumber but rather make sure they know boilers inside and out first.

So I lost faith and decided the problem was manageable, its the same story with a car we still have SORN on the drive, it has drive the odd time and loses it at others, without going into that in too much detail we had at least 5 mechanics look at it, one had it for 3 months and now over a year later we still have nobody who has a clue where the problem lies, i'd guess its within the ton of wiring but as Oilhead says nobody seems willing to apply themselves yet they are happy to try and charge for failure.

Thanks for your help