Impossible to fix flow problem? 4 grand down so far...

[Harvest Fields]

Oooosshh. How many copper pipes do you have coming from the boiler itself?

Good question.

 

[sammathias]

Picture of under the boiler at connections?

 

[Gasmk1]

no bypass ?

 

[sammathias]

no bypass ?

I think that's the least of his worries.

 

[Gasmk1]

i know it looks like a shocker of an install

 

[Karl]

Ask around friends, family or even the local plumbers merchants for a highly recommended heating engineer! Word of mouth and reputation is the best advertisement
Good luck

 

[AMGasServices]

Is it me or are the flow and return pipes looped together ? (if you look at the second picture on the second row)

 

[chris watkins]

I know I said I would come back but
if you paid £4k for that you were quite royally tucked up mate. 22mm equal tee before the pump what is that for ?
York, E/F & compression used, there are 2no. 22mm couplings on a 150mm length in-between a tee & elbow, more like wiped joints than soldered, get a pro in & stop messing around.

 

[AMGasServices]

I agree with Chris.

Personally I’d rip up the piping the cylinder cupboard and around the boiler and repipe the lot.

 

[Darryl Pullen]

Pictures might be a bit confusing. Connections are at the top of the boiler, just 2, 1 flow, 1 return. They are not looped together but the pic makes it look like it. 3 pipes into the roof. Flow going up, and two returns from upstairs. H/w return and upstairs rads. They join the pipe from the flood on the far right, downstairs return...

 

[Darryl Pullen]

Some of that pipework in the boiler cupboard a crap DIY job previous owner must have done to pipe in a shower pump. Not linked to heating circuit.

 

[AMGasServices]

I have uploaded a image how your systems should look but it is not 100% correct as there are a few things missing.

 

[Darryl Pullen]

Thanks. So even so some of the pipe work is a bit shoddy right. There seems to be nothing fundamentally wrong. Flow up to pump, into auto valve and feeding dhw tank and/or rads. H/w and rads returns all into boiler cupboard. Pressure tank on return in boiler cupboard with filling loop...

 

[Darryl Pullen]

Expansion vessel, not pressure tank! Couldn't remember the words.

 

[sammathias]

22mm equal tee before the pump what is that for ?

Looks like the old feed and vent, can only assume it's capped off higher up and not just isolated on that 15mm gate valve.

The flow and return does loop together by some form of close coupled tee arrangement.

If your certain that that motorized valve is working correctly and the wiring is correct it probably is a blockage 'solder' .

In picture 5 you could unjoin the two 22mm tees far right and see how it performs.

Basically with that complete mess it's going to be impossible for us and best to get a 'plumber' to rectify that pipework.

 

[Rob Foster]

It might be an idea to fit a second hand pump on the rtn, wire it straight to a plug, plug it in let it run all the time on fast and see what happens. 2nd hand pump is dead cheap

 

[Darryl Pullen]

I have two spare second hand pumps! I wondered if that would be ok to try that?

 

[sammathias]

I disagree.

 

[Darren Jackson]

Which way is the arrow pointing on the pump body? Hard to see on your picture. Also if the boiler was connected when flushed it could be full of crap now. Might be worth cleaning out the hex, plate & F/R valves.

 

[sammathias]

Darryl I will ask again but reword it. How many connections/tappings/valves are there on the underside of the boiler?

 

[Darryl Pullen]

Thanks again for taking time to respond. Got Viessmann coming out today to check the boiler.

Will check the pump arrow direction, and will confirm if there are any pipes and connections at the bottom of the boiler from memory just one, plastic pipe?

 

[sammathias]

Ohh hopefully they don't condemn that boiler then. Let us know how you get on and weather they resolve the problem.

 

[fixitflav]

connections at the bottom of the boiler from memory just one, plastic pipe?

That's probably to be the condensate drain.

Consensus is it's likely to be low or no flow causing the problem. Re-reading your original post, I would guess the system has never worked, and the old boiler would have been fine if the flow issue had been sorted.
Assuming it is low flow, it could be due to a blockage or maybe the way the piping is installed. A sketch of the complete system would be useful, but not easy to prepare as much of the pipework will be out of sight. On a working system you can get some idea by following rising temperature round the system, but that's catch-22 in your situation.
Keep us posted about how you get on with Viessmann.

 

[Darryl Pullen]

So, Viessmann came and went. He was adamant (obviously) that it was a flow problem! In his opinion, it is a blockage in the heat exchanger. This is because it does indeed behave exactly the same on just HW as CH. Possibly caused by powerflushing the system with the new boiler connected (as was mentioned), so has flushed some gunk down in to the heat exchanger.

His suggestion, get the boiler powerflushed, or just heat exchanger removed and cleaned fully. Put a magnaclean or some kind of filter on the return...

 

[Darryl Pullen]

He only determined it by measuring flow and return temps. But was sure.