HELP PLS: Boiler, HS Megaflo versus Gledhill Pulsacoil

[neeway2000]

When our apartment block was built the builder's contractor messed up on the Megaflo installations in all 14 flats, putting the wrong bore pipe leading down from the tundish to the ground. The installations don't meet building regs.
To resolve this, the building company has ruled out replacing the pipework because it would be costly and very difficult for them, and instead wants to replace the unvented Megaflo boilers with Gledhill Pulsacoils, a different type of system.
It is difficult for us to know whether this is a good suggestion, or would leave us with a worse system (Megaflo is great). e.g. would we lose pressure, or efficiency, or have higher long-term repair costs etc?
Anyone able to help? Is this a good switch, or should be be saying WHOAH THERE!
Many thanks

 

[glasgowgas]

you are saying it would be dearer to upgrade the D2 pipework, so they aregoing to fit 14 brand new units?

 

[Norcon]

Why not use the soil stack?

http://www.nhbc.co.uk/NHBCPublicati...ical/StandardsExtra/filedownload,34921,en.pdf

http://www.redbooklive.com/pdf/042-97.pdf

 

[morrismini]

Pulsacoil is good, no probs.

 

[muggles]

Pulsacoils aren't all that great, hang on for grim death to that Megaflo

 

[neeway2000]

you are saying it would be dearer to upgrade the D2 pipework, so they aregoing to fit 14 brand new units?

Thanks all.
Yep. 14 flats over 4 floors of a building with concrete flooring that at its thickest is about a meter thick.... they say the cost and difficulty of accurately drilling down through each flat into the basement to install new pipes is prohibitive, and I can see their point even though I don't like it.

Regarding using the soil stacks, I will ask them about that.. thanks. But I believe that the layout of the flats makes that a problem too. The boilers are not near the bathrooms, and the floors are concreted with electrical underfloor heating in them, so laying new piping at sub-floor level doesn't seem an option. I will double-check, but I know it was considered and rejected.

So thats 1 vote for Pulsacoil being ok, and another saying it doesn't compare favourably with Megaflo. Looks like this is not as straightforward a question as I had hoped

Thanks again... more opinions would be great!!

 

[Agile]

The only person who supports the pulsacoil is a retired fellow who is not an installer or a repairer. He only reads brochures and has already been banned from this forum several times before for posting inaccurate information.

It should be possible to use a £5 item to enable the discharge to be piped into an existing internal drain.

Tony

 

[neeway2000]

The only person who supports the pulsacoil is a retired fellow who is not an installer or a repairer. He only reads brochures and has already been banned from this forum several times before for posting inaccurate information.

It should be possible to use a £5 item to enable the discharge to be piped into an existing internal drain.

Tony

Thanks Tony. Any idea how I can get more details of this option so I can challenge the builder? Oh, is that the waterless HepVo valve mentioned in the NHBC doc above? (Thanks for the link to that, by the way, Norcon!)

 

[gas4you]

Stick with the Megaflo.

Gledhills appear to be a pension fund for us engineers

 

[doitall]

I would think the builder would be happy with a solution, assuming he's the one paying, and the Hepv0 is perfectly acceptable.

I vote Megaflow any time.

 

[picasso]

megaflo gets my vote as well.

 

[Corgigrouch]

I Thought that Gledhill had gone bust.... Heatbanks are a nice idea but overly complicated and hense can give more trouble.. Megaflows are nice and simple and very reliable.... Less parts to fail.

Oi Morris, How'd you get on with your wayyy over complicated start stop pumped DHW that was fitted to the light switch and a PIR?

OP If you can find the post where Morris discussed this idea, then perhaps you will realise his credentials... Gave us a good laugh

 

[davebgas]

Megaflo for me!

 

[billy bob]

You are better off keeping the megaflow, tell the builder you do not want the unit changed, as someone else has pointed out the builder could take the discharge pipe into the soil system of the house via a hepvo trap, this is accepted by the building regulations, as long as Polypropylene is used for the discharge pipework not standard PVC waste pipe

http://www.redbooklive.com/pdf/042-97.pdf Figure 3 on page 4

 

[htgeng]

I removed a faulty pulsacoil around 2 years ago that had been installed to an 'all electric' flat. I say faulty because the control pcb had an intermittent fault that Gledhill wouldn't come out to replace and the store itself was leaking. Once I had peeled all the foam insulation off, I found 3 or 4 leaks from one of the seams of the tank. This had leaked into the airing cupboard causing damp downstairs.

I replaced with a Santon 170 unvented. But sure, don't take our practical experience and install a pulsacoil as it will mean more callout work for someone in the future