New Radiator, different pipework - Sealed System

[DLaing]

I want to replace an old bathroom radiator with a swanky new "designer" one. The problem is that I have a sealed central heating system which would need draining to allow me to change the pipework.

The web pages I've seen helpfully state that I should "consult a professional".

Surely it can't be that difficult to drain and the refill the system?

 

[Registered Gas Man]

Look for a drain point. Should be on a downstairs rad; you are able to attach a hose to a drain point, which should give you a clue as to what to look for.

When refilling, make sure you fully bleed the system, to fill locate your filling loop which is near the boiler ( Or inside depending on your boiler type)

I have given such basic instructions, as i am assuming you have a knowledge of what is required and just want confirmation that this is an easy job ( Which it is; if you have a bit of common sense )

If you need more details post again and ill try and help out!!

 

[DLaing]

Thanks for the prompt response.

I have to admit that I've never noticed a drain point but I shall go in search later.

When you say fully bleed - is there anything specific I should do when refilling? I imaging the system fills from the bottom up, so is it simply a matter of opening the bleeder valves down stairs until the radiators are full and then closing and moving upstairs until they are all full in turn?

Are there any possible complications (air locks etc)? It all sounds very easy but best to check!

 

[roshko]

Hello DLaing (& everyone),

I too have a sealed central heating system that needs to be drained, and like you, have only seen web pages that advise me to "consult a professional."

I've drained an open system before, so I think I should be able to tackle a sealed system.

Can anyone tell me if there is anything I should watch out for or be aware of (apart from the things mentioned already)? Are the steps for draining a sealed system similar as for an open system (i.e. open the bleed valves on the radiators upstairs first, then downstairs and do the opposite when refilling?) Are airlocks a concern?

I've located the drain point already and I've read how to re-fill my combi boiler (a Worcester 24CDi), so I am just wondering if there is anything else I should know before I begin.

DLaing, how did it work out for you? Any nasty surprises?

Thanks everyone!

 

[DLaing]

I drained and refilled last weekend without any major traumas. The only problem I had was air in the pump and boiler when I had topped the system back up to the operating pressure.

I solved this by opening the pressure release valve while the filler tap was on. This seemed to re-prime the pump and fill the boiler.

Everything is working fine now.

 

[tahirh]

I need to do the same but am a bit of a novice.

My combination boiler has a heating return pipe going into the boiler with a valve on it.

Do I need to close this before draining the heating system?

 

[doitall]

Same rules apply now as they did in 2004.

Make sure you know how to re-fill it before you drain it.

Why would you want to drain it.

 

[gassafeman]

READ THE DATE THE OP POSTED THIS TOPIC!

Paul