Twin Header Tanks

[postman]

Hi Everyone, new to this forum and as with all newbies I have a plumbing question:

I have a problem with the cold water pressure in the bathroom with the biggest issue being cold tap on the bath, I have just moved to a cottage which is spring fed, not on mains water, the cold feed comes into the house and is stored in twin header tanks in the loft, each tank holds 40 gallon max.

Tank 1 has the feed coming in with the ballcock and feeds primarily the hot water tank which is situated just underneath it, the tank is full to almost the overflow, it also has a 22mm pipe at the side near the bottom feeding tank 2.

Tank 2 has the feed coming in from tank 1 and feeds the small bathroom, toilet and washhand basin and the large bathroom which has a toilet washhand basin and bath, I am unable to check the fullness of this tank because the previous occupants have converted part of the loft and carried it through to where the tanks are situated, I have removed the 22mm connecting pipe and there seems to be no blockage on the pipe.

As the biggest issue is with the cold tap on the bath I have noticed that with tank 2 the feed coming from it to the bathrooms is 22mm, however after approx 4ft of piping this is reduced to 15mm, then when the pipe comes out the wall in the bathroom it goes from 15mm to 22mm then onto the tap? the 15mm pipe also feeds the 2 toilets and 2 washhand basins.

I am thinking that the problemm is 22 to 15 to 22 on a large tap with air going back up the pipe and causing an airlock however would welcome all thoughts and suggestions to help resolve.

Thanks Pat

 

[WaterTight]

So the hot flow is ok in bathroom? And just the cold is rubbish? How bad is it?

If tank 2 is fed by tank 1 I would have thought it would have to be full to the same level as water finds it's own level. This should mean roughly the same flow even if pipe sizing restricted it somewhat (which it can.)

I think the main thing usually is how high the tanks is above the outlets but if the hot is fine I would guess the head (height) is fine.

I suppose there could be half-closed valve, some debris in the pipe, a generally badly piped set-up, air, or any number of other things... Bring in the big brains!

I step aside..

 

[postman]

Hi there, thanks for the reply, the cold water goes down to just a trickle as if you have left a tap running.

The tanks are at the highest point in the apex of the roof and are also above the hot water tank which flows very well, one thing I have only just noticed is the hot water is in a 22mm pipe from the tank to the bathroom so i am maybe thinking this is the issue?

I will be doing up the bathroom as soon as I have figured out how to resolve this issue and I am thinking of running an additional 22mm pipe from one of the tanks directly to the bath tap possibly using alkathene piping as I have heard this is possible, hopefully, no doubt if it isnt somebody will let me know.

 

[justlead1]

Hi Unlike main supplied water yours is not adjusted (Ph etc) so you may have a bit of corrosion / muck slowing things down. Get a length of curtain wire and see if you can put it down the end of the feed in the cistern? You can wriggle it about a bit, with cold tap flowing it may shift any muck. Improving the flow.

 

[WaterTight]

I'm not saying pipe-sizing isn't an issue but I've seen quite a few tank fed pipes changing from 22mm to 15mm for part of their runs and it doesn't have a huge impact. If you have a good flow in 22mm then reducing it to 15mm isn't going to restrict it much at all. And certainly not to trickle. Presume blockages/sludge and go down that line first.

 

[postman]

When I moved in I fitted a filter system, UV light and PH balancer, however thats not to say there is any residue in the pipes prior to this and I am unable to access the 2nd tank to put a coathanger into the pipe, when you turn the taps on you get a good initial flow then very soon it goes down to a trickle and like I said before tank 1 the feeder tank is full so dont think its amount of water in the tank?