Megaflo Woes

[Nickspoon]

Hi - We have a loft mounted Megaflo CL145HE, which was installed about five years ago by a “professional” plumber – to cut a long story short, we had to get a new plumber in to sort it out as the heating / hot water did not work correctly. At first he claimed to be trained to work on these cylinders, but eventually admitted he wasn’t and could not sort out the problems. So we got a third plumber in, who was definitely qualified (we knew to check by now!) and started sorting it all out but the firm went bust before he had finished :disappointed: But at least it finally seemed to be working!

Now the Combination reducing valve has started leaking badly, so before getting anyone new in I have started researching how it should be connected, so I have an idea of what I am talking about this time? Don't get me wrong - I just don't want to be ripped off again.

The 3 bar valve has a cut-off valve attached, but both are mounted below the base of the cylinder with the 8 bar pressure relief valve on the pipe between it and the cold water inlet – there is no drain-off point. The discharge from the 8 bar valve is 15mm & goes direct horizontally via a T-piece into the 15mm discharge pipe from the T&P valve where they meet at floor level – there is no tundish! The discharge is all 15mm and after a meter or so connects to plastic overflow type pipe right across the loft and through the gable wall, coming out high up & to one side of the main entrance to the house – if it happens to be leaking and the wind blows the wrong way anyone coming to the door thinks it’s raining! We had a massive amount of work done on the house and none of it has ever been properly signed off by Building Regs as the building firm left so many small jobs unfinished, the inspector came round and said he could not pass it and we haven’t seen or heard from him since – though he never directly mentioned the Megaflo.

My questions: I assume the discharge pipe should be all copper? and 22mm? after the tundish - when fitted. Can it be re-routed to connect to an outside soil stack? (we are on septic tank drainage). Am I right in thinking the cold water inlet also needs re-routing to bring it above the inlet port and high enough to allow the 8-bar discharge to join the T&P discharge pipe high enough to leave room for a tundish? Or can it be left where it is and the 8-bar discharge run uphill so to speak, to achieve the same result? though this would not leave space for a drain-off point from the cold inlet, which should be provided?

Hope this all makes sense!

 

[townfanjon]

Quite simply my friend you need a G3 registered engineer in there.
Post up your location somebody will help you I am sure.
I would be happy it could all be 'sorted' though

 

[Nickspoon]

Thanks for that - my research has already led me to realise I am going to need a professional in - I am just trying to get my head around what is required, as have had bad experiences in the past - we are near Ribchester, Lancs.

 

[Best]

You have a few things wrong (by your description) that are not serious, but are obviously done by someone out of their depth. Lack of a drain off point is one of those.
But the discharge pipe is a serious issue. It has to be a diameter of pipe to suit the total length of the discharge pipe which also has to allow for each bend. This is 22mm minimum!
Why go into any detail about it? You obviously know it is wrong & you need your building certificate, - so get a qualified engineer to redo anything that's incorrect & don't try doing it yourself as the discharge pipe is critical to be done right.
I would turn the water off to that unit & get it sorted tomorrow.

A discharge pipe can have overheated or overpressurized water or both coming out of it & could cause serious injury if not discharging to a safe point.
Also the unit can explode if it can't discharge - take a look on YouTube unvented cylinders exploding.

 

[Best]

MythBusters - Exploding Water Heater - YouTube

 

[chris watkins]

If you were having that much work carried out you must have been aware / done some research, as to what was required under the Building Regulations i.e. drainage (Part H) wiring (Part P), heating/cylinder (Part L) & of course hot water (Part G).

If you have genuinely been ripped off by a builder than I do feel sorry for you but you will excuse me for being a little sceptical sometimes as we have a few "self builders" who want to DIY to save the cost of a "proper certificated plumber" (which the Law requires) & when things go wrong they make out it is just so they don't get done again !!
Either way, as above the posts, you need a proper certificated plumber now ask to see their card or certs & make sure they have good experience in this field.
They might not be want to give you chapter & verse on what is required for the reasons above but most will provide an outline & of course sort out the Building Control certification. Get a couple of quotes for the work required before you appoint someone.

 

[SimonG]

Bit of a tangent to this and aimed at the g3 guys.

In an instance like this how would you deal with building control. Tbh I wouldnt touch the likes of this with a barge pole, unless I was charging over the odds to assume the responsibility. I would be more concerned around the stuff you cant see.

I think ill stick to new installs, services and repairs as farcas unvented go.

 

[Nickspoon]

The posts on here seem to be getting a bit harsh towards me now - I replied an hour ago to townfanjon to say I am intending to get a professional in, but my post has still not showed up. I am not an idiot, I do know the consequences of an out of control unvented cylinder - even if the TV show that did this had to deliberately circumvent every safety device fitted. Yes I can put shelves up, change a lightbulb even! decorate, do tiling, put in kitchen units etc etc - But NO I do not do major wiring work and up to now have not touched any of the plumbing. I was advised to put in a Megaflow by the building firm, whose plumber fitted it and messed the whole thing up in the first place - he also nearly ruined a brand new Worcester oil fired boiler, before my research as you put it made me realise something was very wrong and order him off my property - well that and the 45 kilo vertical radiator falling off the wall and nearly killing my young son!

The builder calmed me down and promised to get a new plumber in who he had checked had the certification to put it all right - I accepted this, but things started to go wrong again as he could not get the hot water and heating to work together - I asked to his certification and he finally admitted he had none - no unvented cert and no Oftec - yes I was furious and refused to pay him - sadly I had been paying on a weekly basis up to then, so that was no big deal to him - but by then we were running out of money.

After having to shell out a couple of grand to get the roof put right that the builder also messed up (new lead flashings stuck over the old with silicone, to name but one fault), we finally had enough saved to get another plumber in (yes - unvented certified) - not easy as I doubt many of you relish sorting out other people's mess ups, which I quite understand - he got cracking and sorted the valves etc and the connections and was to return the week after to do the supply and I assume discharge but the firm went bust. He hadn't told me exactly what the problem was and as things were finally working, until the leak two weeks ago I had no idea it was serious.

So please forgive me if I seem a little up tight and somewhat OCD with the detail I go in to now, but I now like to know exactly what I am dealing with - i am near Ribchester in Lancashire and any recommendation for a certified firm to sort this out gratefully received - but I do want to understand the solution required.

 

[Nickspoon]

Bit of a tangent to this and aimed at the g3 guys.

In an instance like this how would you deal with building control. Tbh I wouldnt touch the likes of this with a barge pole, unless I was charging over the odds to assume the responsibility. I would be more concerned around the stuff you cant see.

I think ill stick to new installs, services and repairs as farcas unvented go.

Thanks - that really fills me with confidence about getting this sorted out!

 

[Best]

It's typical a builder causing the problems in the first place & I don't disbelieve you. You probably would have had better luck sourcing your own properly qualified plumber. But a builder often wants to interfere & 'sell' you a plumber that he takes a cut of the cost.
Guys on here don't want to give out too much detail as some people are doing it themselves when clearly incapable & sadly, even the first two "plumbers" you had were obviously not plumbers.
I would take the builder to court.

 

[Ermintrude]

Don't tell then what's wrong with install, let them tell u.

Ok there are a few faults with mega flow install well get them sorted ASAP. Your first port of call should be the manufacturers instructions for the mega flow. Review the instructions in conjunction with your install and compile questions (not faults as u may be wrong)

Secondly I believe that the discharge and issues u may be having are due to the loss of the bubble in cylinder. Look at mI and read section on reforming bubble.

 

[Best]

Agree^^^. Manufacturers instructions adhered to are all that is required, plus a qualified & capable plumber. Life is simple if you have a good plumber. :smile:

 

[SimonG]

If all else fails RTFM.

 

[Nickspoon]

Thanks for the positive replies - Yes I have been reading up and realised bubble probably needs reforming too, which looks straightforward enough, but as I read more and recognised there were other issues, l realised I need professional help. Can you just answer one question that bothers me - the only place I can see to route the discharge too would be across the shortest side of the attic, where there is a soil stack on the outside - don't need detail as I won't be doing the work, but is this feasible? Also I realise my interpretation of what I have read may not be correct, so will certainly not be telling anyone I get in what needs doing - I just want to be able to understand what they tell me!

The initial plumber worked mainly for a local housing association on their old people's flats!!!! The second was from a local firm who at the time had a very impressive website showing lots of their "previous work" though I now doubt it was! Wish I could get the third guy back, but think he moved out of the area when the firm went bust.

 

[SimonG]

Any piccies?

 

[Killy Bing]

Thanks for the positive replies - Yes I have been reading up and realised bubble probably needs reforming too, which looks straightforward enough, but as I read more and recognised there were other issues, l realised I need professional help. Can you just answer one question that bothers me - the only place I can see to route the discharge too would be across the shortest side of the attic, where there is a soil stack on the outside - don't need detail as I won't be doing the work, but is this feasible? Also I realise my interpretation of what I have read may not be correct, so will certainly not be telling anyone I get in what needs doing - I just want to be able to understand what they tell me!

The initial plumber worked mainly for a local housing association on their old people's flats!!!! The second was from a local firm who at the time had a very impressive website showing lots of their "previous work" though I now doubt it was! Wish I could get the third guy back, but think he moved out of the area when the firm went bust.

post up your location in the I'm looking for a plumber or gas engineer for a forum member to get in touch to do the job.

no playing the lottery to get a competent engineer as you can look back at our forum activity helping out.....or poking fun at each other !!

 

[chris watkins]

Not A good idea to take a loft installed Megaflo & run the discharge waste straight to drain cos how are you going to see when the bubble goes again (water through tun dish). That wastes water & could lead to it scaling up of safety valve or leaking into building etc. Why can't it be run down to low level.
See a good plumber, who as we keep saying will run you through the options.
I am out of here, good luck Nick.

P.S. thats the trouble with having an un-regulated Plumbing sector Nick, any one can claim to be one & it ends up costing you a fortune.

 

[tamz]

I'm Spartacus :smile:

 

[Nickspoon]

Think the first plumber threw out the manual :disappointed: The original motorised valves were not fitted and dissapeared too and he fitted a different single three-port valve in their place - I had to buy new ones and the third plumber sorted this out - to my (very) untrained eye it now appears to match the online installation guide I have seen - which makes changing the timing belt / water pump on my Citroen C5 look easy!

Pics as requested - silver insulation to right is just a roll end stood there until I find a use for it - all insulation under the front of the cylinder had to be removed as was soaked by leaking combination valve (hence orange biscuit tin!) and all loft and pipe insulation I admit done by me as there was none whatsoever!

 

[Dannypipe]

Nick, if you truly want a qualified plumber to look at this. Put your details up, and someone will get in touch. If you are after technical advise, you will be left wanting as we don't want to be held responsible if you undertake it, and make a mistake.

 

[townfanjon]

Dannys dead right Nick, post your details, sorry you are so far away, otherwise I would be happy to come over to 'THE DARK SIDE' and help.