HELP! plumbing advice needed Esse WD & simple gravity

[niftysteve]

Are you a plumber Nifty?

 

im not a plumber but i may take some eveneing classes to gain certs so that as a hetas installer i can fit boiler set ups and maybe some bio mass heating

[difflock]

Simplistically all one requires to do is attempt to ensure that the hot cylinder is located as nearly vertically as possible above the range or stove.

And the higher above the better.

Then keeping bends and fittings to a minimum ensure that the pipework always rises (even the nominally horizontal runs if these are needed to route the pipework) towards the hot cylinder, then in the top of the coil, out the bottom and again constantly falling back toward the heat source.

I would suggest keeping all in 28mm, (one could possibly use cheaper Hep"0 once a couple of metres away from the boiler, though harder to keep straight/ rising gently.)

Since colder water is denser the hot water will always rise to be displaced by the cooler ret flow.

One can insulate the pipework, absolutly no reason not to, though perhaps some merit in leaving the return flow pipework uninsulated.

Referred to as a "Thermosyphonic" system I believe.

One must ensure an open vent at as high a level as possible in sufficiently large diameter pipework to allow the stove to boil & vent steam for safety.

This is generally simply a continuation of the hot pipework from the boiler rising on up vertically and then curving back down to discharge back into the header tank.

Or taken up through the roof and curved back down.

 

Plus a gravity fed cold supply, from a header tank or cistern.)

I am not a plumber:001_tongue: but have successfully plumbed:001_tt2: a couple of houses.

Edited December 11, 2012 by difflock

[Pumpy]

to add to difflocks info, presuming it's a new build and not connecting to original plumbing, it's not the hot water tank that has to be high as possible, it's the cold water header tank... which provide the pressure to the system for showers etc, so the hot water & cold water are the same pressure, your mains supply feeds this cold water tank via a ballcock. As in your standard "Airing cupboard" you have the hot water tank at floor level upstairs, a storage space above it with lat shelves up to ceiling height, and the cold water tank directly above in the loft. You need another (smaller) header tank (usually in the loft) for the boiler circuit - this is the "open vented" bit. This is also mains fed via a ballcock, so both tanks need overflows!!!

 

Having installed a similar system, I found it helped to draw it out in 3D with red and blue pens for pipe runs, I used 28mm for the whole boiler circuit, you also need a radiator in this circuit (usually in the bathroom) which has to be open "on" all the time i.e. must not be able to turn off, (this is to dump heat and prevent the system boiling) I came off the 22mm with 15mm to the rad, one for the feed and same for return.

 

The boiler circuit must also have a drain valve at the lowest point of the pipe run to enable you to drain the circuit should you need work on the pipework etc. (I put mine behind the boiler on the Hunter stove) I put stop valves in the CW feeds to the tanks, saves having to turn the water off to work on the system. There are additives you can get from a plumbers merchant, one to clean out the boiler circuit from flux etc during install and another to leave in the system to help prevent boiling/calcifying, don't add these until you've tested the circuit hot, two of my boiler connections had slight leaks and I had to drain the system to fix them (doh).

 

I could take pics of the pipe work if it'd help

 

edit: Think about forward planning with the HW tank, will you be wanting solar hot water in the future kind of thing, or HW from another logburner on the same HW circuit, if so it'd be worth getting a HW tank with 2 coils so it's an easy add on later rather then swap out the HW tank

Edited December 11, 2012 by Pumpy

[difflock]

Sniff,

I Had no leaks, though after persistent pestering from the brother I reluctantly tested my plumbing by connecting my pipework to the 4 bar mains pressure.

Before pouring concrete floors throughtout.

Unfortunately I forgot to isolate the copper hot cylinder, which attempted to turn itself inside out.

Whilst I enjoyed a beery supper.

However a 1/2 plastic drum under its permenantly deformed arse, and 15 years later all is fine.

PS

Good point btw Pumpy about the second/spare coil, an omssion I still regret.

[Pumpy]

Good point btw Pumpy about the second/spare coil, an omssion I still regret.

 

You and me both mate, you live and learn

 

nat - I remember stressing over the install, biggest plumbing job I ever did with 6 rads also coming off the boiler, wife saw me stressing for a few days so she got me a book that saved my bacon (which if I'm honest I thought would be useless) "Plumbing Heating and Gas Installations second edition by R.D. Treloar - blackwell publishing" invaluable book as it turned out, has all the regs in, how to work out boiler size, rad size etc.

[Alycidon]

I am not a plumber but managed to plumb our Esse gravity feed in very easily although I would suggest fitting a Laddomat to keep the boiler temperature up and make the stove run efficiently. PM me and I could run through the pipework we ended up with for hot water and a thermal store.

 

ESSE offer a boiler control unit that does the same thing, it allows the cooker to get up to temperature before allowing cold water to return to the cooker. Fits external to the cooker in the return water pipe.

 

these are the WD installation instructions from the Esse website: it contains a few pipe diagrams.

 

http://www.esse.com/support/cookers/installation-instructions/wd_install.pdf

 

Hope that helps

 

 

A

Edited December 12, 2012 by Alycidon

[Perkins]

You know it is possible to operate a pressurised system if, for example, your house is a bungalow and you can't get the header tank high enough to generate sufficient pressure. You'll need a mains-pressure hot water tank and expansion vessels on both the central heating circuit and hot water tank, and a pipe-stat on the outlet from the coil that triggers the central heating pump to operate. This will protect the system from overheating and dump the heat into the radiators if you stack the stove full of logs and turn off the circulating pump.

[Perkins]

you also get the benefit of mains pressure hot (and cold) water, without the need for a header tank.