Indirect Unvented cylinder, Combi Boiler and Nest Thermostat

[Harvest Fields]

Yes or no?

Do you have to install to MIs?

I’m sure there is nothing in the Vaillant manual that shows you how to pipe in 2 zones for a larger house yet Vaillant say you can fit their 938 into a 4 bed semi with a bathroom and ensuite. So does that mean on a new build you would put the whole system on one zone? @Bibbs118

 

[Bibbs118]

Look, you are missing the point, one, seeing it done loads does not mean it's OK, two, vaillant will have a drawing for an s plan plus, three, doing it so it's safe in your mind is not the same as installing to MIs.

And four. Yes or No, do you have to install to MIs?????

If there is no instructions then how can you follow them, this is why I did say, get a drawing from the manufacturers .

 

[hammers4spanner]

You can put a combi on unvented have seen it done numourous times . One hot draw off to utility basin in most cases.

Even done a greenstar with a worcester enginger couple year ago.
If anyone would know about their product they would.

As said another heat source.

 

[Harvest Fields]

Look, you are missing the point, one, seeing it done loads does not mean it's OK, two, vaillant will have a drawing for an s plan plus, three, doing it so it's safe in your mind is not the same as installing to MIs.

And four. Yes or No, do you have to install to MIs?????

If there is no instructions then how can you follow them, this is why I did say, get a drawing from the manufacturers .

You’ve answered you own question. If they have a schematic for an s plan then yes you can.

 

[Bibbs118]

You can put a combi on unvented have seen it done numourous times . One hot draw off to utility basin in most cases.

Even done a greenstar with a worcester enginger couple year ago.
If anyone would know about their product they would.

As said another heat source.

Please re read what put. Seeing it loads off times does not meant it's OK, this is why I did say get a drawing.

And , s plan zones don't require temp and pressure relief of or a temp cut off do they? So not the same .

 

[Bibbs118]

Yes or no, do you have to install to MIs?

 

[ShaunCorbs]

Ffs

 

[Harvest Fields]

Think we have to just disagree on this one @ShaunCorbs @Bibbs118. I trust what Vaillant told me and that’s that.

 

[Harvest Fields]

Please re read what put. Seeing it loads off times does not meant it's OK, this is why I did say get a drawing.

And , s plan zones don't require temp and pressure relief of or a temp cut off do they? So not the same .

No idea what world you live in though mate.

 

[Bibbs118]

Think we have to just disagree on this one @ShaunCorbs @Bibbs118. I trust what Vaillant told me and that’s that.

Being told something is not the same has following the MIs, what am saying is, if you can't get a drawing then it's not ok .

Because it's impossible to follow MIs without having the MIs .


Just ask yourself the yes or no question and the answer will tell you what I'm saying is correct .

Do you have to install to MIs? Yes or NO

 

[Harvest Fields]

Being told something is not the same has following the MIs, what am saying is, if you can't get a drawing then it's not ok .

Because it's impossible to follow MIs without having the MIs .

If the manufacture say it is ok. And they warrant the job for 10 years then it is ok. But for future reference I will make sure they email me confirmation. On that not I’m done. I will not be commenting again.

 

[Bibbs118]

If the manufacture say it is ok. And they warrant the job for 10 years then it is ok. But for future reference I will make sure they email me confirmation. On that not I’m done. I will not be commenting again.

That's totally correct, you need confirmation.

 

[Harvest Fields]

That's totally correct, you need confirmation.

I was being sarcastic. But honestly I’m done now

 

[hammers4spanner]

Re read what I wrote.

I have done this with a worcester engineer employed by worcester.
It is acceptable.

 

[townfanjon]

Just come in on this one , will read it all later , just back off holiday, FFS phones going mad .

 

[Bibbs118]

Re read what I wrote.

I have done this with a worcester engineer employed by worcester.
It is acceptable.

So worcester can authorise an invented cylinders on say a vaillant combi or baxi?????

 

[Bibbs118]

I was being sarcastic. But honestly I’m done now

If you don't have it in writing then you are not following instructions are you .

Just answer questions

YES OR NO DO YOU HAVE TO INSTALL TO MIs?

 

[hammers4spanner]

Can worcester authorise one of their own products ?
Of course they can .
A worcester was fitted on such set up and fitted and authorised along with guarantee themselves.

Job done money in the bank and all happy

 

[Bibbs118]

Can worcester authorise one of their own products ?
Of course they can .
A worcester was fitted on such set up and fitted and authorised along with guarantee themselves.

Job done money in the bank and all happy

That ok, am not saying it can't be done, am saying the poster needs a drawing, if no drawing is available then it's not permitted .

And saying I've seen it done loads of times does not mean it's right, I've seen loads of flue not clipped but that doesn't mean it's right .

 

[ShaunCorbs]

You don't need a drawing / tech schematics

Doesn't mean it's unsafe or manufacturer arnt going to warrenty there boiler

Hell even if you fit the unvented incorrectly I'm sure they would still warrenty there boiler

 

[Bibbs118]

You don't need a drawing / tech schematics

Doesn't mean it's unsafe or manufacturer arnt going to warrenty there boiler

Hell even if you fit the unvented incorrectly I'm sure they would still warrenty there boiler

So what your saying you DONT need to install to manufacturers instructions? Interesting.

 

[ShaunCorbs]

So what your saying you DONT need to install to manufacturers instructions? Interesting.

More like common sense

 

[hammers4spanner]

In all honesty I would say 90 % of boilers I cone across are not installed as per MI

 

[Bibbs118]

More like common sense

The as long as you use common sense you don't have to follow MIs?


What if your common sense differs from my common sense. Because my common sense says always and without exception install to MIs, but you your common sense says something different

 

[Best]

I am not gas qualified, so won’t comment on anything gas.
The unvented cylinder will be to regs if heated by a controlled heat source of oil or gas boiler and the 2 port valve supplied with the unvented unit to be in operation, controlled by uv stat.
A combi used with extra zone, or solely a zone for unvented or vented cylinder hot water I would have thought was fine and to MIS.
The space heating main body part of a combi boiler is just the same as a heat only system boiler anyhow, - isn’t it?
But sure it only takes a phone call or email to the boiler manufacturer to confirm.
I know combi boilers are installed on homes where there is some sort of hot water cylinder (vented or not) so to give option of mains pressure hot water at some outlets, or to provide instant hot water at a supply close to where the gas boiler is sited, - like a kitchen tap.