How do I drain hot water cylinder?

neil1965

Hope someone can help? Tommorow I plan to replace the copper hot water cylinder in the airing cupboard. After switching of the main stopcock and running all the water out of the hot taps how do I go about draining the water from the cylinder (from what I understand the outlet for the hot water is at the top of the tank and after running all the hot water out, the cylinder will still be full!). There does not appear to be any facility to drain the cylinder on the inlet side. Have I understood things correctly or am I having a senior moment!

All advice eagerly recieved! Neil

Canucklehead

Hi: First of all, we'll assume your hot water is heated by the boiler therefore you have an indirect cylinder...that gives you 4 connections i.e.cold water in, hot water out, flow and return from the boiler.The lowest connection is cold feed which would normally have a drain off and a valve to isolate it (usually red handled)..rather than draining the whole tank in the roof try this valve first. If it is quite an old cylinder you might find another tapping around the bottom of the cylinder with a drain off made into it. Quite often I wouldn't bother with the drainoff as they usually stick and you end up spending 2 hours draining a cylinder through a pinhole:alternatively, undo the tapping at the top, feed a hose in and siphon (put a bit of 15mm copper tube on the cylinder end of the hose to help send it to the bottom). If you are lucky, the two connections from the boiler can be disconnected without draining the heating i.e. top connection will have a motorised valve on it and the bottom connection should have a gate type valve...this should allow you to undo the 2 connections. Be aware, the new cylinder connections will not match up...if you haven't done this before, be prepared for a weekend of fun :eek:

Good luck.

HTH

Corgi Guy

neil1965

Many thanks for above advice. Am just off to start the job now(fingers crossed).

EliteHeat

Canucklehead wrote: »

...if you haven't done this before, be prepared for a weekend of fun :eek:

I am sure that I remember reading on here that this job will take a maximum of two hours.

plumb1_2

EliteHeat wrote: »

I am sure that I remember reading on here that this job will take a maximum of two hours.

Only for some:rotfl:

http://forums.moneysavingexpert.com/showthread.html?t=445257

ormus

aye and it takes some pros 2 days and they get 1500 quid for it, i seem to remember?

Canucklehead

ormus wrote: »

aye and it takes some pros 2 days and they get 1500 quid for it, i seem to remember?

I assume that as the OP posted on MSE he didn't pay £1500 and therefore the 'plumber ' didn't get £1500.
Maybe someone else did but, as they say, 'buyer beware'
Corgi Guy.