megaflow for what

[emphasis303]

Hi

Ive got a vaillant ecotec 600(not sure what 600 exactly) condensing boiler, aswell as an Ariston Primo Unvented Indirect ITI 210 cylinder, however everytime two showers are running or hot water is being used in two different places at the same time the pressure drops and the hot water goes cold for a split second. is there a way to sort this so that each tap or shower isnt affected by another. the pressure for the system is also at 2 bar. Another thing is a lot of the time when drawing hot water the pipes thump quite loud then calm down, have tried lowering the pressure and heat but still does the same any ideas?

If anyone has any ideas as to why this is happening it would really be of great use.

I will also try to get the boiler model tmrw.

Thanks

 

[ChrisR]

Water supply from the road to the cylinder is probably undersized.
What flow rate in litres/minute do you get from the garden tap.
Less than about 25l/min will be aproblem.

 

[emphasis303]

Hi
thanks for your reply, you said the supply from the road??, but the hot water is being drawn from the cylinder? if what uve said is right, i dont think im geting 25l from the garden tap ill have to check but if this is the case what can i do about this

thanks

 

[simond]

Emphasis 303 wrote

paid about 500 for installation, took just under a day

Would this be the same unvented cylinder you got such a good deal on mentioned in another of your posts today (see 'cost of installing a megaflow cylinder')? I don't recall you saying you weren't happy with it?

Somebody has the byeline on this forum 'pay peanuts get monkeys'. Never a truer word...........

 

[Agile]

Hi
thanks for your reply, you said the supply from the road??, but the hot water is being drawn from the cylinder? if what uve said is right, i dont think im geting 25l from the garden tap ill have to check but if this is the case what can i do about this

thanks

How on earth do you think the water gets into the cylinder if it doesn't come from the water mains in the road???

Pipework to each outlet should be in 15 mm back as close to the cylinder as possible but 22 mm when shared with other outlets.

A good solution is to use a manifold and a 15mm from the cylinder to each outlet.

As Chris says the incoming mains flow rate has to be measured! If its inadequate you need to upgrade the supply pipe from the road.

Your £500 installer should have had the certificate and explained all this to you and done whatever was necessary to give the correct operation.

Tony

 

[emphasis303]

Hi

loool some of you make me really laugh, bcos i paid a decent amount doesnt mean i got in some cowboy, he was a friend of the family, qualified and certified to the teeth corgi nvq the lot, he wasnt some guy i just picked up off the net and said i want this and this, regarding the pipeline off the road, what i am saying is that when the hot water is turned on the boiler doesnt heat the water and send it within the 5 seconds the hot water gets to my tap does it, i understand the water is from the road but the boiler heats it and stores it in the cylinder, then when i call for it, it doesnt come from the road but from the cylinder?

aswell it is all 22mm as far as i can see,

how ever i am still at a loss as to why it matters that much on the pipeline from the road, i was only talking about my hot water not the cold, and if the taps are drawing from the cylinder which is already full of hot water then what part does my road play? it only supplies the water to be heated right?

thanks for the input guys

 

[gas4you]

The supply from the road has to be at leasy 3 bar and at least around 20 l/min flow rate.

If you haven't got this coming from the road, then you haven't got enough cold water to 'push' the hot water out of the cylinder at the correct pressure or fast enough to cope.

The un vented cylinder is directly connected to the cold mains.

Is your fitter G3 registered? Corgi means nothing with un vented cylinders.

 

[simond]

So when you said you got the whole job for £500 you disingeniously omitted to say that it was a friend of the family.

Therefore every 'not plumbing savvy' person reading your post expects to negotiate the same rate.

Regarding the flow rate from your HW as Dave says there is no motive power in your steel cylinder, so what comes out is what goes in. If you have a boggo water supply that is what your unvented cylinder will deliver.

Those of us who are fortunately not part of your extended family take measurements of the flow and pressure before recommending a solution. I would have demonstrated to you exactly what flow rate you could expect using my flow meter.

 

[giblets]

Megaflo's require a absolute minimum of 20l/min in their installation instructions.

 

[Agile]

Your certificated friend of the family does not seem to have done the basic checks which any competent installer would do.

£500 is quite a reasonable installation charge and does not show any discount of the lower end of the trade prices.

What he seems to have discounted is the preliminary tests and recommendations ffor improving the mains water flow rate.

Also you seem very reluctant to call him back to complain about the inadequate performance.

I am also very critical if he has pipes all the HW in 22 mm as that will slow the delivery time and waste energy. I guess he has not insulated any of the hot water pipes either??? ( Required by regulations now too! ). Did he notify the local Building Control Department?

Tony

 

[emphasis303]

Hi

thanks alot for all the comments guys, I havent actually mentioned this to him regarding the pressure dropping from a tap when another one is turned on. The pipes were already fitted before moving in, regarding insulation, it was just a straight swap for the cylinder it wasnt a new installation and the cylinder was fitted 2years ago and all the pipes are situated under the floorboards so would they still need insulating?, when the water is running its fine its when more than one hot water tap is running that the problem comes. I can call him back regarding this, its only that it came to mind whilst on here so i thought i would ask, i wasnt actually around when the work was done, hence why im not sure if a flow test was conducted and all the tests were done, i will find out and get back to you, im pretty sure he would of done all of this however as i said will double check.

 

[emphasis303]

just checked, flow rate was tested he is g3 certified, he checked the flow the week before installation, doubt he would have installed the cylinder if it wasnt ok. and the piping to taps etc is 15mm, so if anyone who actually has the same cylinder or has tried it out via showers taps can post whether when they have more thann one tap on the pressure drops or not it would be appreciated

 

[giblets]

it was just a straight swap for the cylinder it wasnt a new installation

I'm afraid that is classed as a new installation and as such should meet all the current regulations regarding insulating adjacent pipework, notifying the Local Build Control Dept, running the correctly sized discharge pipe, etc.

One question that has not been asked - what type of shower roses/outlets do you have? If they are the "watering can" type roses then this will cause problems with the flow rate to other outlets. It does sound as if the incoming main to the house is not big enough to cope with the required flow rate. When you turn on a cold mains tap is the initial flow quite strong and then reduces?

 

[Agile]

You have not made it clear if the problem has been apparent ever since it was first installed. It sounds as if this is that case?

You can measure the flow rate at each shower and add them together to see if it exceeds the minimum 20 li/min which if its open pipe flow is the absolute minimum for an unvented cylinder at a reduced performance.

If its only recent then there is an inlet filter which might have become blocked. However this will have been checked during the first annual service. You did have it serviced didn't you?

Tony

 

[emphasis303]

the cold water can run for ever with out being affected so can the hot,its only when another tap is turned on the problem occurs, the showers are watering can type, also before the new cylinder was installed when the kitchen hot water was on one of the showers would go cold but the other shower was fine, however upon installing the new cylinder any hot water used anywere now affects all of the showers, as i said no pipework was changed only a straight swap for the old one to the new one