Issue with Water System

[leon7788]

So for any of you out there which may have some experience or be in the trade i have an issue with the workings of the hot water flow through the house. I have had a plumber come down to look at the issue and as yet cannot seem to solve it and will be asking another friend of his who has more experience to give advice...

The problem is that the cold water is over riding the hot for example:

The water in the bath runs hot yet the shower head will only run hot when the bath is running otherwise it comes out cold.

In the down stairs showerroom however the water from the shower will not run hot no matter what other water device is turned on yet when the shower is running the tap in this room and the kitchen will turn hot.

There is no problem with the boiler as it is only 5 years old (megaflow) and nothing wrong with the cylinder as the plumber checked it.

if anyone could help would be greatly appreciated

Thanks leon

[thinfourth2]

Gravity system or pressurised hot water system?

[Simpo Two]

Colw water is mains pressure and the hot is probably gravity fed, hence the difference.

Mind you if the issue has only started recently then you need to ask somebody clever like Ferg.

[m4ckg]

If its a Mega Flo I think that it runs off mains pressure

[Ferg]

The problem may well be that you have a very high mains pressure and the Megaflow has been incorrectly plumbed.

Hot is NOT supplied at 'mains pressure', rather it is supplied at 3Bar by virtue of the PRV on the Megaflo. It may well be that the mains in the street far exceeds this. (I came across 9Bar the other day!!!!!)
Colds to mixer valves should be supplied either from a balanced port on the PRV OR a tee after the PRV.


You COULD fit a PRV on the rising main to bring it down to the 3Bar required by the Megaflo....

Bear in mind that this is a diagnosis by Internet....a proper survey would be best.

[Scraggles]

had similiar problem, got a PRV under the kitchen sink, stopped the hammering on the pipes

[Simpo Two]

Ferg said:

Bear in mind that this is a diagnosis by Internet....a proper survey would be best.

Forums are great! I came across a splendid dialogue about an 'absorbtion fridge', something like

Poster 1: My fridge doesn't work.
Poster 2: Neither did mine but I turned it upside down and it's OK now.

[JM]

Simpo Two said:

Forums are great! I came across a splendid dialogue about an 'absorbtion fridge', something like

Poster 1: My fridge doesn't work.
Poster 2: Neither did mine but I turned it upside down and it's OK now.

That's one way of 'fixing' and absorbtion fridge, depending on the problem with it.

[Simpo Two]

I just had this mental image of a happy fridge user, happy despite the fact that all the shelves had fallen out and his groceries were splattered over the ceiling...

OT: What do you know about absorbtion fridges? I am investigating one for a boat and it has to be electric (12V). Is it a choice of 12v Normal vs 12v Absorbtion, or are they all absorbtion anyway? PM if preferred.

[leon7788]

thanks very much for the responses!

got to say didnt expect such knowledgeable answers!

Will be passing this information on again thanks!

[Dogwatch]

JM said:

Simpo Two said:

Forums are great! I came across a splendid dialogue about an 'absorbtion fridge', something like

Poster 1: My fridge doesn't work.
Poster 2: Neither did mine but I turned it upside down and it's OK now.

That's one way of 'fixing' and absorbtion fridge, depending on the problem with it.

Worked for me many years ago. General idea is that you restore the fridge to the conventional position afterwards though....

Removing the contents and shelving first is also recommended.

[johnthegas]

Just to echo previous advice - Are the colds on your outlets fed from a balancing valve? Sounds like the colds could be straight from the mains and therefore will be at a higher pressure than the hot.
The balancing valve will be an in line brass tee thing fitted after the pressure relief valve on the cold feed to the Megaflow.
Again, internet advice is no substitute for a survey - let us know how you get on mate.

[leon7788]

well i got it all sorted told the bloke what had been suggested and you were right the pressure coming in was 6 bar so got it reduced to 4 bar now everything perfect! (he assumed that the water board could have increased the pressure) so thanks to those helping me out!