DIY Doctor UK DIY Forums

Hello, I have a slight problem with my plumbing system at home and hope that someone here may be able to help. I have searched the forum for similar posts, but I believe my issue is slightly different !

Basically, I have warm (sometimes hot) water from every cold tap in the house (including the wc and outside taps). I have an electric water heater in my cellar supplying each of the taps but no central heating. Unlike the previous posts on this issue however I have no water tank as my water is pumped directly from our natural spring. It's very annoying as I don't really want to spend the summer watering my garden with hot water or wasting precious heat every time I flush the toilet !

Any advice would be very greatly received :)

Hi
I would first turn the water heater off for a few hours and check the cold water then behaves normally.
You can then be sure the warm water is heated by your water heater before entering the cold taps.
If that is the case it can only be getting there via a mixer tap or shower (or possibly the heater pipe itself).
If you feel the cold water pipes coming away from these after turning the heater back on you should find which warms up first. That would be the source of your problem.
Hope it works.

thanks Mr B, that sounds like a sensible place to start, will report my findings :)

cheers

I am only guessing and not a plumber but these are my thoughts if you look back in here.

My thoughts are 'back flow from heater' made worse turning on cold tap/s.
First find where the heater feed connection is on the cold feed pipe and then trace back holding the pipe to see if hot/warm to where the cold taps feed T piece is, turn a cold tap on see if the cold feed pipe to cold taps gets hotter.this will then prove 'backflow is ocuring if the pipe is warm/hot.

Most if not all boilers have or should have a back flow prevention valve on the inlet to prevent hot water flowing back into cold feed pipe as feeds are Tee'd from the cold feed depending on site. If this has been like this since heater installed then your heater may not have a none return/backflow valve so hot water is progressing back in turn heating cold water. Fitting a none return valve between the heater and cold water Tee feeding the cold taps should cure the problem.
At least you don't have a water bill coming in.

that is also a very logical reason/solution for what is happening. I had hoped that there was simply some kind of air-lock in the top of the boiler, and that emptying it completely then refilling/boiling would fix the prob. Alas not so, i think it was a bit too hopeful of me to think it would be such an easy fix. Waterever warm water comes out of the cold tap is def mixing with cold, however, as it's just luke warm, not full temp and last I estimate for between 5 and 10 litres before going completely cold again. Will tackle it again tomorrow and report back ! Thankyou for your help guys, very much appreciated.

thanks fellas you were spot on, there is no non-return valve hence the backflow running freely. I will attempt to buy the correct valve and fit it, and am absolutely sure that I'll be back on here when I cock it up !! Really appreciate your advice. Great forum :)