Before I go ahead and destroy my central heating...

[pezzer]

In short... we've bought a new house and are in the process of renovating/extending it, and need to make some changes to the central heating (install radiators upstairs, and move/upgrade the hot water cylinder, relocate header tank as it's on the same level as upstairs radiators...). Now, I will start with: I'm not a plumber, but I've done a fair bit of work on CH systems before.

So the first thing i was going to tackle was moving the header tank and putting a radiator in our bedroom (it's bloody freezing!), but now I've actually inspected the pipework, it's a bit of a mess. It's currently an S plan, and the pump/boiler/valves are downstairs, and the cylindar (rather small one built in header tank) and CH feed tank are in the room above. But the pump is on the return next to the boiler with motorised valves before it, and the vent/feed/expansaion pipe comes from the top of the pipe feeding the cylindar. On top of that, the pipework near the boiler is in a small gap next to it, and a right bloody mess.

So I'm now looking for advice as to what to do with it all. Do I:

1. leave it as it is, but just move components - ie, feed pipe for cylindar goes upstairs, then branches into vent pipe up to loft, and pipe to cylindar in another room downstairs. How bad is this option as far as venting goes?

2. replace the mess downstairs with a 'normal' S/Y plan ie. boiler->vent->feed->pump->valves + bypass (oh yeah, currently no bypass, and all the radiators have trvs On that note - stick with S plan with 12 year old valves, or use a spare barely used 2 port valve I have laying around for Y?

3. Assuming I don't go with option 1, I have another variant - moving the pump/vent/valves to the airing cupboard where the new cylindar is going. This might be convenient as it's in the middle of the house, and will probably reduce pipework necessary for central heating, and it;s going to be easier to run pipes from the loft to here for vent/feed.

My concern is, if I go with option 1, it's going to be such a bork, something probably wont work. Option 3 is probably easiest for me to do, as there's less faff than reusing dodgy existing pipework, and I can install most of the new system before cutting off the old.

Any suggestions would be greatly appreciated!

 

[joe-90]

Why not pull it all out and put a combi in? Use whatever pipes are useful and ditch those that aren't. Messing around bodging the old system is a mug's game.

 

[JohnD]

Agree with fitting a whole new system.

I like cylinders, they can give good fast flow for a bath, and are not prone to severe loss of flow at one tap if someone turns on another tap somewhere else.

I agree that combis are quicker to install and are OK for a single-occupant home with shower. However they are also less reliable.

 

[Nige F]

Convert it to a sealed system , then you can forget the feed/expansion tank. Vessel etc. under a £ton.

 

[pezzer]

Thanks for the suggestions...

I'm not a fan of combis... one of the main reasons I want to sort the heating out is cos I miss the power shower from my old house! Also we're on oil, and I've heard oil combi boilers are next to useless. We're also probably going to install another shower, so I figured a cylinder was the way to go.

I also would like to keep the current boiler for now. If (when) it packs up, we'll probably replace it with an external system boiler.

I guess converting it to a sealed system wouldn't be such a bad idea. Although if I'm putting in a new loft tank for the hot water cylinder, then it's no real effort to put in an expansion tank... I suppose we could save a bunch of hassle getting tanks into the loft, and go unvented with the hot water cylinder. I've never worked on these, so wouldn't be doing that myself, so any idea what it's going to cost for someone to convert it to an unvented sealed hw/ch system?