Good enough for an unvented cylinder?

[jason61c]

Evening all.

Scores on the doors.

Static 7.5bar.
flowrate 18lpm
dynamic 5.5bar.

28mm ish incoming, going straight to a 15mm stopcock/pipework.

I guess I should see the flow increase with 22mm? More importantly is that good enough for a unvented jobbie?

 

[TCCHeating]

Just about! Should really be 20lpm min but, as you have said, upgrading the mains after the stop cock and the stop cock itself from 15mm to 22mm should improve the flow rate enough to get you over the 20lpm minimum

 

[jason61c]

is there a calculation you can do to go from 15 to 22mm?

 

[dreadnoughtheating]

Dearest Jason,

Assuming (and from your opening post I have my doubts..... ) you have full 'G3' accreditation, your course notes/manufacturers installation instructions will tell you all you need to know.

BTW, with which body will you be registering this new install for Building Regulations purposes? (its the law).

Not too sure at this point I would choose to be a neighbour.

DH

 

[doitall]

Are we assuming Dear Jason is DIYing it

At the given pressures I would expect a far greater flow rate, 2bar drop says to me the pipe is restricted before the stopcock

 

[jason61c]

Thanks to all the doom mongers

I'm not DIY'ing it. A friend is doing it who has all the accreditation. I'm doing my homework on what I need to buy so I can get the bits as and when I can at the right price.

 

[jason61c]

Dearest Jason,

Assuming (and from your opening post I have my doubts..... ) you have full 'G3' accreditation, your course notes/manufacturers installation instructions will tell you all you need to know.

BTW, with which body will you be registering this new install for Building Regulations purposes? (its the law).

Not too sure at this point I would choose to be a neighbour.

DH

Why not? You'd get the work fitting it after I've sourced all the parts.

You'll know full well what it says in the notes, minimum needed flow rates and pressures, 'best' of the previous etc, hence my well structured questions and readings etc

 

[TCCHeating]

Why didnt you ask your friend first before asking on here. If he is fully qualified and is going to fit it for you surely he could tell you all you need to know.

I'm starting to think drednought may be correct in assuming you are going to diy it

 

[Agile]

I was thinking that too!

I don't understand the first post either!

It would be normal to measure the dynamic flow rate which leaves say 1.0 Bar pressure.

Tony

 

[doitall]

The flow rate for the size of pipe and pressure is still a question, as is the pressure drop

 

[jason61c]

Why didnt you ask your friend first before asking on here. If he is fully qualified and is going to fit it for you surely he could tell you all you need to know.

I'm starting to think drednought may be correct in assuming you are going to diy it

Because I don't want to bother him more than I have to, he's doing it for free as I've done some stuff for him. What's the problem with my questions? I'm sorry drednought is upset with me asking questions.

 

[doitall]

Don't worry about it, it gets a lot worse sometimes.

 

[jason61c]

Don't worry about it, it gets a lot worse sometimes.

I'm not worried, its the way of the trolls. Its good that positive responses/answers outnumber the above.

 

[TCCHeating]

I gave you a proper answer didn't I? was just curious as to why you didnt ask the installer thats all! You have to understand that for a lot of folks on here this is their business and how they put food on the table. They have invested a lot of money in training so they obviously don't like people who are unqualified taking work from them. Surely you can understand that. (Not saying you are in any way lyeing. In fact i think you are probably being genuine). But there are a fair few people who post on here that take the ****. No one has trolled you. Maybe some were just doubtful about the authenticity of what you were saying. Which is fair enough in my opinion, especially when dealing with something like an unvented cylinder, which I am sure you can agree, can be very dangerous if installed wrongly. Just be grateful you got some help on your post.

 

[muggles]

It would be normal to measure the dynamic flow rate which leaves say 1.0 Bar pressure.

Tony

Listen to Tony, he speaks the truth - what's your flow rate at 1.0 bar pressure?