Help-Domestic system, hot water pressure

[Les]

Dear All,

As a DIY'er now trying to plumb our self build house, I would be grateful for any help you can give.

The system is a simple indirect vented system. The problem is that the hot water distribution pressure head seems lower than that which the cold water tank fills up to. Water doesn't make it's way back up to the cold water tank vent pipe. The hot water level gets to about a metre short of the cold water tank level, which isn't enough to make it back up to the loft to reach the pipes around bathrooms etc. Even I can remember that water should find it's own level, but this system seems to defy that rule!

Any help or tips? thanks in advance-Les

 

[stevetheplumber]

Dear All,

As a DIY'er now trying to plumb our self build house, I would be grateful for any help you can give.

The system is a simple indirect vented system. The problem is that the hot water distribution pressure head seems lower than that which the cold water tank fills up to. Water doesn't make it's way back up to the cold water tank vent pipe. The hot water level gets to about a metre short of the cold water tank level, which isn't enough to make it back up to the loft to reach the pipes around bathrooms etc. Even I can remember that water should find it's own level, but this system seems to defy that rule!

Any help or tips? thanks in advance-Les

Thats impossible water will always level out. is the tank sitting on the same floor level as the appliances ?if so it will not work the water will stand at the same hieght but not flow bottom of tank needs to be higher than the outlets to get any flow
raise the tanks or fit pumps

 

[Beeline]

Does the cold tank feed the hot tank? If so i believe you need to run direct feed from your mains to the hot tank. There shouldnt be a vent pipe feeding into the cold water tank either, so maybe their mixed up. Pipe sizing also effects this, as say a 22mm supply from cold cistern would lose pressure if rising again in 15mm.
You can also lift the hot tank in the attic, this will give a little extra pressure on hot.
Confusing!! post more details we might be able to give more help.

 

[Les]

Thanks gents, problem now solved; it was an airlock.
I was inspired by it being impossible (thanks), so capped off the vent, and sucked through a tap like a human pump. A drip became a trickle, then bubbles and finally a jet left me on a high.
Many thanks for your help-Les

 

[Plouasne]

Reading these postings, I despair of how some of you became plumbers in the first place

Water will only find its own level if it is not restricted by some means, the frictional resistance on the pipe wall if the pipe work is under sized, is enough at times to stop water finding its own level

If a mains supply is directly connected to a vented hot water cylinder, one of two things will happen, 1) the cylinder will burst because it can not stand the pressure, 2) water will pi55 out of the open vent

My kids knew better than the advice given in some places on this forum, when they were 10 years old

 

[Phil]

"Does the cold tank feed the hot tank? If so i believe you need to run direct feed from your mains to the hot tank. There shouldnt be a vent pipe feeding into the cold water tank either, so maybe their mixed up. Pipe sizing also effects this, as say a 22mm supply from cold cistern would lose pressure if rising again in 15mm.
You can also lift the hot tank in the attic, this will give a little extra pressure on hot.
Confusing!! post more details we might be able to give more help. "

[DLMURL="http://www.ukplumbersforums.co.uk/report.php?p=23160"]

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Can you enlighten me how you came by this information?

 

[Plouasne]

"Does the cold tank feed the hot tank? If so i believe you need to run direct feed from your mains to the hot tank. There shouldnt be a vent pipe feeding into the cold water tank either, so maybe their mixed up. Pipe sizing also effects this, as say a 22mm supply from cold cistern would lose pressure if rising again in 15mm.
You can also lift the hot tank in the attic, this will give a little extra pressure on hot.
Confusing!! post more details we might be able to give more help. "

[DLMURL="http://www.ukplumbersforums.co.uk/report.php?p=23160"]

[/DLMURL]​

Can you enlighten me how you came by this information?

Phil,

I would think it was a case of consuming too much, falling down liquid, or some kind of code to the other poster, because none of the posting makes sense

 

[Phil]

Does the cold tank feed the hot tank?

If so i believe you need to run direct feed from your mains to the hot tank


There shouldnt be a vent pipe feeding into the cold water tank either, so maybe their mixed up.

 

[Plumbstar Tom]

Although there are numerous things wrong with the statement from BeeLine lets not be harsh.

Whilst he is wrong we should take the mickey he was trying to help. I know they call them selves plumbers and come out with false info but we are here to show them the way.

If he continue to think this and decides that he needs to run a direct feed from the mains to the vented hotwater cylinder there is high potential of injury! Not something we want on our conscience

 

[Plouasne]

Although there are numerous things wrong with the statement from BeeLine lets not be harsh.

Whilst he is wrong we should take the mickey he was trying to help. I know they call them selves plumbers and come out with false info but we are here to show them the way.

If he continue to think this and decides that he needs to run a direct feed from the mains to the vented hot water cylinder there is high potential of injury! Not something we want on our conscience

But do these 6 week wonders take the advice of those who have been longer in the game and seen the problems first hand, I doubt it, whilst some might do, the majority seem to think that they are the ultimate in plumbing, going by the posts in the forum

 

[Plumbstar Tom]

But do these 6 week wonders take the advice of those who have been longer in the game and seen the problems first hand, I doubt it, whilst some might do, the majority seem to think that they are the ultimate in plumbing, going by the posts in the forum

I fully understand

We are in a phase where you do a six week course and you class yourself as a fully qualified plumber ready to take on the world. But clearly errors mentioned in this particular thread that are a danger if carried out and an unsuspecting newbie who realises they have only the very basics and need to learn from experience may read the above and not understand the reasons why it is a danger and carry it out. It may seem obvious to you but do they know how thin the copper is on the hot water cylinder and why mains on it is crazy?

I think they do take advice, how many people have viewed the thread on hints and tips. Its clear to me who has the experience on the forum and I take note of what they say. I obviously cannot comment on behalf of the others be hope they do.

Does the cold tank feed the hot tank? If so i believe you need to run direct feed from your mains to the hot tank. There shouldnt be a vent pipe feeding into the cold water tank either, so maybe their mixed up. Pipe sizing also effects this, as say a 22mm supply from cold cistern would lose pressure if rising again in 15mm.
You can also lift the hot tank in the attic, this will give a little extra pressure on hot.
Confusing!! post more details we might be able to give more help.

BeeLine,

I sorry to say this

I suggest you read your post and consider why it is wrong in numerous ways.

Learn from your errors and improve your self

 

[secret squirrel]

Plouasne,

I'm sure that in your many many years of plumbing and having children that are plumbers at the age of 10 you have had many apprentices and they have grown up and had apprentices etc. When your passing on your valuable (not meant sarcastically) hard earnt experience with plumbing I'm sure you managed to do it in a constructive and informative manner without barracking your apprentice.

When your apprentice says something a little ridiculous or inappropriate did you constantly slap him down or just "nudge" him/her in the right direction!

I get your point you don't like "fast trackers" as I'm sure everyone who reads your posts gets. BUT when your writing advice or answering a post with information I for one read it with interest and DO take notes and a more often than not people respond with "thanks for that" "I'll go and buy one of those" "makes sense" . As soon as you put a little "bile" or "hate" in it, it detracts from the good practise and common sense approach you have.

I agree with plumbstar, if some one is putting mains into a cylinder (oops vented) and thinks thats ok then there error needs to be pointed out to them......if they get barracked and insulted for replying then they won't post and stop this bad (dangerous) practise.

So in conclusion Plouasne, I like reading and learning from your posts but for my own sanity "stop the hate, make love not war"

 

[Phil]

I'm about 18 months in and learning all the time. There has been times where I've relpied to questions but then cancelled before posting if there was any dout in my mind as to the accuracy of the statement.

I'm a member on all the major plumbing forums and I have to say this one has the worst reputation for wrong and dangerous advice, blind leading the blind etc.

I was gentle with him, he would have been ripped apart on Screwfix for example.

 

[Plouasne]

I am sorry if I come over sounding hard, I do try to be gentle with most of my postings, and do try my best with those who were not in the fortunate position that some of us older plumbers were in by being able to have an apprenticeship
My old mate said to me once, before you ask a question, think about it, then think about it a bit more, then if you cannot find the answer, ask the question, but that was aeons ago, and the highest words of praise from your mate, was not bad matey, not bad matey, when you had slogged your nuts off doing the job
Example: My mate challenged me to a race in doing a job, just a simple 31/2" pulled lead bend 921/2°, from setting out the bend on hard board, to the finished job, this was in the time of proper paraffin blow lamps, not the fancy gas jobs you have now, from the word GO, it was an all out job, 20 minuets later he had finished pulling the bend, it took me half an hour, by that time my mate just to rub salt into the wounds so to speak, had "flapped out" the dresser marks in the lead pipe, and polished it with tallow and hessian, so it shone like silver, and his words to me were, yep you have guessed it, Not bad matey, and when the two bends were put together, to see if there was any discrepancy in the bends, the famous words, "its own mother would have thought that they were twins", high praise indeed, the only time he was behind us newbies, in the game was in lead burning and bronze welding copper tube

 

[Beeline]

Dear All,

...The problem is that the hot water distribution pressure head seems lower than that which the "cold water tank" fills up to. Water doesn't make it's way back up to the "cold water tank vent pipe." The hot water level gets to about a metre short of the cold water tank level

Any help or tips? thanks in advance-Les

I shouldnt have posted i was confused by the description of this system and had a swift couple on the way home. lesson learned.
I misunderstood what is the tank for the hot water cylinder with the storage tank for cold water distribution and couldn't understand why the cold distribution cistern had a vent pipe. I "meant" the hot water cistern should have a feed from the mains, again misunderstanding the original post i thought it was fed by the cold distribtution cistern. I would never suggest to connect mains cold to anything but unvented and only then through the PRV.
again i was far too confused and shouldn't have posted.

BTW i did a course at leeds college of building, it took me three years. , and im Gas safe registered and never had a correction order, i have my bpec unvented and water regs. I run my own business which is 90% reccomendation and am currently studying towards my solar and heat pump qualifications.

I dispair at some of the advice on here too
I wonder how many of these comments i would have got to my face and not over the net.
Some reasonable slaps round the head for posting while confused and in error, and some very critical and pompous replies phil and plousne.
And i thought this was an open forum.. seems like a clique so i wont be posting again.

 

[migoplumber]

beeline, please post again. everybody unless they are perfect give bad advice, be it here or in the pub. at least here there will be somebody on your tail to remind you thats not right!
its not just a learning curve for the diy'ers asking for advice, everytime bernie makes a post i learn something myself.
some people will cut you down harsher than others, dont sweat it, thats life!

shaun

 

[Phil]

Beeline, if you're gas safe then you're more qualified than me, I'l probably edit my reply but you have to admit reading it back its bizzare!

I've posted the odd wrong advice on here and been totally ridiculed by members!!!