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Topic: Plumbers... (Read 536 times) previous topic - next topic

Plumbers...

Any plumbers (or people who know more about plumbing than I do) out there?

Putting a sink into the garage along with one of those over sink water heaters.

Since it's going to be working for it's living and probably regularly filthy didn't see the point in worrying too much about appearances or going new.

Found everything used either locally or on eBay and relying on internet owners instructions which aren't always available or uptodate.

Currently trying to get my head around water pressures.

Re: Plumbers...

Reply #1 –
I plumbed the whole house including the central heating.  Got a Gas qualified plumber in for the boiler though.

You should have mains pressure at your boiler but it will drop when you draw water.  The drop will be determined by the length and diameter of the pipe to the boiler.

Re: Plumbers...

Reply #2 –
I did some plumbing for the first time in our bathroom about 23 years ago. I used proper copper pipe and Yorkshire joints ( the ones with a solder ring ). Worst bit was doing the taps. I plumbed in the old basin pipes since they were nicely formed and used flexible joints for the bath with fibre not rubber washers. Had a few leaks with the rubber washes and tested the basin taps without the waste fitted but I can laugh about it now!
Plastic pipe and push fittings were in there infancy then and I was warned against them but as with everything the quality has probably improved since then so that could make the job easier.
If you go the Yorkshire joint route remember to empty any water from the run you are soldering since it will dissipate the heat and won't solder. Hehe how I learnt the tricks of the trade the hard way!
Good luck.
1991 Tornado Red BB 8v GTI Moredoor
2008 Skoda Octy Scout aka dirty diesel

Re: Plumbers...

Reply #3 –
Think I've sussed the various connections, it's just the volume of different types / measurements used that was initially hard to follow.

The garage is detached and there's an outside tap between the main doors. The mains water comes onto the property via a 25mm blue pipe and that tap is the first in the system before it heads off into the house itself.

The sink's destined to be on the wall behind the outside tap (literally the thickness of a wall away), and have already bored a hole through to 'T' piece it into the garage, all good.

From there it'll reduce down to 15mm copper pipe with a direct feed to the cold tap and one splitting off to the over sink heater... all very straight forward.

What's causing some head scratching is the water heater itself. The electric side of things is all OK, no input needed there.

The water pressure into the house (at the outside tap - which if I've understood correctly is coincidentally supposed to be the best place to check) is 7 Bar.

The heater has a max. of 10 bar but that is not it's operating pressure and you are supposed to insert physical 'reducers' into heaters cold water inlet (at the tanks bottom) to bring that down to a certain level so as the thing'll work properly (too much pressure and the incoming cold will overwhelm the stored hot) but more worryingly not potentially explode.

There's a table supplied to let you work out the correct reducer depending on your water pressure.

Not being new, I've since found my heater didn't come with the 4 x choices of reducer you'd get with a new one and sod's law means they can't be bought separately.

I've since got an in-line adjustable pressure reduction valve that has a range covering that of the 4 x genuine reducers.

I've a water pressure gauge so should mean getting it exactly right against their requirements.

My brain is saying there's no logical reason this set up shouldn't work, but I'm not a plumber! 

Re: Plumbers...

Reply #4 –
If the original reducers were washers with different size holes in then they will only reduce pressure when the water is flowing. If you have 7bar in the pipe before the reducer and water is forced through the pressure after may drop to 5bar for example. Stop the flow and the pressure at both sides of the reducer will be 7bar.
More sophisticated reducer valves with springs in are available for about £30. Never used one but I believe they drop both static and dynamic pressure. Some have gauges so you set the pressure you need.
Edit, I see that you have bought a pressure reducer valve. I’d fit it and test it.

Re: Plumbers...

Reply #5 –
Also don’t forget service and isolating valves.
I would have brought the supply into the garage then out to the tap via an isolating valve. That way I can isolate the tap from freezing winter and still have my sink and hot water. Each tap would have a service valve that would be set to balance pressures. I would also isolate before the reducer so the whole new set up can be serviced / maintained.