CH expansion tank fitting

[Jethro_uk]

as winter approaches going to sort this out once and for all, so a few quick Qs for those that know better than I ...

1) For a 10-radiator bungalow, an 8L tank is suffice ? 2) I need to cut into the return pipe (22mm) and insert a tee-piece ? 3) which I then feed into a 22mm->3/4 inch tap connector which screws onto the expansion vessel ? 4) Copper tubing and fittings 5) flush system while I am there ... 6) and refill with inhibitor (again - grrr !!!!)

Luckily there's quite a bit of headroom in the boiler room, so mounting the new vessel

heating-8-litre) should be a few moments work.

(ponders shutting down server which is on a shelf opposite)

[newshound]

When I fitted mine, I included a "service valve" that would let me isolate it. Although this is no doubt deprecated, it is safe if you understand the system. Also a standard drain point. You need to isolate and drain these in order to check that they are correctly charged, or to pump them up if they are not. So much easier with the valve and drain point.

[Jethro_uk]

You see, *this* was what I needed. What a very good idea.

[Andrew]

It's quite easy to push a conical bung into the outlet at the bottom of the header tank. Even a carrot wrapped with plumbing ptfe tape will do the trick.

[Michael Chare]

Don't forget the overflow.

[Andrew Gabriel]

Also, don't forget it's an *expansion* tank. The water level needs to be able to rise some way above the fill level without getting to the overflow. The fill level doesn't need to be high at all - just high enough to enable enough drop on the ball valve to give a reasonable fill rate when refilling the system.

I've seen a few systems which overflow when the water heats and expands, and then have to top up when it cools. Very bad for system corrosion.

[John Rumm]

Say its a 100L of primary water, then yup that should do it (you would be unlikely to get more than 4L of expansion)

Yup. (some systems use a flexi style tap connector for this)

Yup.

Remember to order the mounting bracket ;-)