What did i do wrong?

[Luggsey]

So, first plumbing job in years, bought solder, flux and MAP gas as shown.
15mm copper pipe, shined up, fluxed, absolute failure!
I'm a sparks by trade and solder a lot but not with a flame.
Am I right to assume map is far to hot for an amateur to work with, I cooked the pipe!
Advice where I'm going wrong please, I cant afford a plumber!
Cheers.
Paul.
[automerge]1587827746[/automerge]

So, first plumbing job in years, bought solder, flux and MAP gas as shown.
15mm copper pipe, shined up, fluxed, absolute failure!
I'm a sparks by trade and solder a lot but not with a flame.
Am I right to assume map is far to hot for an amateur to work with, I cooked the pipe!
Advice where I'm going wrong please, I cant afford a plumber!
Cheers.
Paul.

As a follow up, these bits are for a shower mixer, can I use JG speedfit for the link to the shower head with the supplied compression fitting or must I use a plastic fitting?

 

[Luggsey]

Now then Paul. All the plastic pipe manufacturers dont warranty their pipes for domestic hot water secondary returns. You need it in copper or mlcp (plastic with aluminium sheath inside).

Ok are we talking about oxygen barrier like underfloor heating pipe?

 

[ShaunCorbs]

Any plastic pipe isn’t suitable for permanent temp eg secondary return

this mlcp MLCP Multilayer Plumbing & Heating Pipe - https://www.bhiveunderfloor.co.uk/mlcp-multilayer-plumbing--heating-pipe-4-c.asp

or copper only

 

[Luggsey]

Any plastic pipe isn’t suitable for permanent temp eg secondary return

this mlcp MLCP Multilayer Plumbing & Heating Pipe - https://www.bhiveunderfloor.co.uk/mlcp-multilayer-plumbing--heating-pipe-4-c.asp

or copper only

I don't doubt you are correct, I just checked JG website...
What dosent make sense is you can use this pipe for central heating return?
I will give it some serious thought but I would keep the DHW temperature low and the return would only be in use for short periods as it's on sensors....
Hmmm.

 

[gmartine]

You need to use MLCP or copper because a secondary return is a continuously circulating HW system, in other words if you use plastic pipe because of the constant heat being absorbed it'll droop like you do after a beery night.

Edit posted sametime OP's last post.
You're using PIR's so secondary return is switched on and off when entering and exiting bathroom/washroom?

 

[ShaunCorbs]

I don't doubt you are correct, I just checked JG website...
What dosent make sense is you can use this pipe for central heating return?
I will give it some serious thought but I would keep the DHW temperature low and the return would only be in use for short periods as it's on sensors..
Hmmm.

Its more down to the oxygen in the pipe degrading the inner walls

 

[Luggsey]

You need to use MLCP or copper because a secondary return is a continuously circulating HW system, in other words if you use plastic pipe because of the constant heat being absorbed it'll droop like you do after a beery night.

Edit posted sametime OP's last post.
You're using PIR's so secondary return is switched on and off when entering and exiting bathroom/washroom?

That's the plan with a temperature sensor at the end of the return before the tank so I can set it to 'just' warm up, can't see a problem tbh but I will check with JG tech when I get chance.

 

[sxdave]

View attachment 43544

So, first plumbing job in years, bought solder, flux and MAP gas as shown.
15mm copper pipe, shined up, fluxed, absolute failure!
I'm a sparks by trade and solder a lot but not with a flame.
Am I right to assume map is far to hot for an amateur to work with, I cooked the pipe!
Advice where I'm going wrong please, I cant afford a plumber!
Cheers.
Paul.
[automerge]1587827746[/automerge]


As a follow up, these bits are for a shower mixer, can I use JG speedfit for the link to the shower head with the supplied compression fitting or must I use a plastic fitting?View attachment 43545

JG Speedfit have a doc. 'Plastic Push-fit for plumbing and heating Technical Information', available on JG website. This gives details of how to use the Speedfit in compression fittings. Hope this helps. If you cannot find it I will try to do so and post the URL.

 

[SimonG]

https://www.johnguest.com/speedfit/wp-content/uploads/sites/2/2019/08/RWC-JG-Speedfit-Technical-Specs-Guide.pdf

Page 15 bottom left hand corner.

 

[Luggsey]

https://www.johnguest.com/speedfit/wp-content/uploads/sites/2/2019/08/RWC-JG-Speedfit-Technical-Specs-Guide.pdf

Page 15 bottom left hand corner.

That's a good read cheers, will have a look for more tips later on.
It does say 'continuous' pumped systems which this wont be because of sensors and temperature sensor of course?

 

[ShaunCorbs]

Still doesn’t matter same situation no go

 

[Scott_D]

Have you fitted the bronze pump and secondary return pipe or is it to be done at a later date?

 

[king of pipes]

Blimey it's kicked off on here a bit 😁 a difference of opinion is good gives us a healthy debate, we all have our ways of working none of us do a job the same way, is it right or wrong I like to have a open mind none of us know it all , I stand by my opinion no secondary needed place the appropriate sized unvented cylinder central in the property keep pipe runs short as practically possible it will work fine why over complicate things 😄😄 stay safe people . Kop

 

[Jim burnside]

View attachment 43544

So, first plumbing job in years, bought solder, flux and MAP gas as shown.
15mm copper pipe, shined up, fluxed, absolute failure!
I'm a sparks by trade and solder a lot but not with a flame.
Am I right to assume map is far to hot for an amateur to work with, I cooked the pipe!
Advice where I'm going wrong please, I cant afford a plumber!
Cheers.
Paul.
[automerge]1587827746[/automerge]


As a follow up, these bits are for a shower mixer, can I use JG speedfit for the link to the shower head with the supplied compression fitting or must I use a plastic fitting?View attachment 43545

Chrome would look better but the fittings your using will work fine.

 

[Luggsey]

I have a Grundfoss bronze impeller pump, movement sensors in all en suites already fitted. I will fit a pipe stat by the pump set to a low but warm temperature.
The pump will only run for short periods evenings and of course mornings.
[automerge]1588056728[/automerge]

Blimey it's kicked off on here a bit 😁 a difference of opinion is good gives us a healthy debate, we all have our ways of working none of us do a job the same way, is it right or wrong I like to have a open mind none of us know it all , I stand by my opinion no secondary needed place the appropriate sized unvented cylinder central in the property keep pipe runs short as practically possible it will work fine why over complicate things 😄😄 stay safe people . Kop

I hope not Kop! I have many more hurdles yet!
It's a pressurised tank with solar and solid fuel coils. 🙂

 

[king of pipes]

Alarm bells ringing bud please please make sure the cylinder is installed by G3 installer and the heat sources are fitted and connected correctly and they are installed with the correct materials , definitely no speed fit allowed to connect to the cylinder, it's a specialist job to be honest and only those who hold the relevant qualifications can fit and work on these. Regards kop

 

[Luggsey]

Alarm bells ringing bud please please make sure the cylinder is installed by G3 installer and the heat sources are fitted and connected correctly and they are installed with the correct materials , definitely no speed fit allowed to connect to the cylinder, it's a specialist job to be honest and only those who hold the relevant qualifications can fit and work on these. Regards kop

Thanks Kop, I'm furlowed at present but work for a large property maintenance and building organisation where I normally ask one of the gas or plumber lads to help out.
I will be getting everything checked and signed off, I have to for the council, but that dosent stop me doing the bulk of the pipework etc.
We went for the pressurised system as we were advised anything less would mean poor hot water pressure in a big house.
Cheers for the continued advice everyone, it is appreciated!
🙂

 

[king of pipes]

Hmmmm agreed a pressurised system is the way to go but it needs to be fitted and commissioned by a approved installer the benchmark completed and signed of with building control 👍 I am no longer qualified for solar or solid fuel but I am G3 and Gas safe others on here will have to advise you on the other heat sources. Kop

 

[Luggsey]

Hmmmm agreed a pressurised system is the way to go but it needs to be fitted and commissioned by a approved installer the benchmark completed and signed of with building control 👍 I am no longer qualified for solar or solid fuel but I am G3 and Gas safe others on here will have to advise you on the other heat sources. Kop

The overheat requriment is likely a rad in the loft with a valve dropping open on power failure. The Bulgarian solid fuel stove (CE for pressurised systems) also has a cold water quench valve as well as the usual over pressure valves. Its proved massively expensive for the solar and solid fuel, I hope it's as good as we expect it to be!

 

[oz-plumber]

Your system design is starting to sound like a Legionella breeding ground.

- Having sensors on the return to only start the pumps.
At what temperature do you wish this to be?

For Legionella protection, the hot water secondary return system should be run at 60C minimum.
If you have long periods of lower temperature water, you run the risk of Legionella breeding.

There are also a heap of other items that you have to concern yourself with, with installing secondary returns.

I don't want to sound harsh, but you are getting out of your depth, really quickly, on this one.

 

[Luggsey]

Your system design is starting to sound like a Legionella breeding ground.

- Having sensors on the return to only start the pumps.
At what temperature do you wish this to be?

For Legionella protection, the hot water secondary return system should be run at 60C minimum.
If you have long periods of lower temperature water, you run the risk of Legionella breeding.

There are also a heap of other items that you have to concern yourself with, with installing secondary returns.

I don't want to sound harsh, but you are getting out of your depth, really quickly, on this one.

I do actually have a legionnaire disinfection qualification from a previous life!
There would be no standing water in the system for more then a few hours?