In order to change and add radiators in my house I had to drain the entire system. I ran into a problem initially involving a leaking isolator valve. Once that was dealt with and upgraded, I had a convenient spot to add a drain off point for my central heating. If you don’t have such a problem, maybe you need to drain the central heating first?
Where is the lowest point of the central heating?
Most the time you should have a drain off valve on either the return or flow pipe on one of the radiators on the lowest point in your system. This is convenient because you can attach a hose to this and feed it outside for minimal mess and easy access.
If this isn’t the case you could have it under the floorboards at an even lower point. Unfortunately for me there wasn’t anything in sight, even with the floorboards up. This meant I was going to have to add my own drain off point.
Work with what you have
I was working with a combi system. This meant it was relatively easy to work on for someone without extensive experience.
My bathroom used to have a radiator in it fed by pipes from the ‘pantry’. We had the bathroom remodelled a couple of years ago and changed the heating to underfloor heating. The flow and return to this was capped off by 15mm compression ends. Without getting under the floorboard level this section of pipe was conveniently at one of the lowest levels on the central heating line.
Discovering the world of Push Fit
I did this at the same time I was making the repairs to the isolation valves. Push fit as I had learned about are the latest in the plumbing world. It’s as easy as lego when it comes to fitting providing you do good prep.
I do end up making soldered and compression fittings across my house afterwards and I’ll cover how I went about it. My main takeaway is that push fit is here to stay. Some traditional plumbers seem to stick their nose at the technology but you can’t dispute that some of the manufacturers believe in it considering they are giving out 50 year guarantees against the parts failing.
Preparation for drain off point
I’ve only had one time when I had a push fit weep on me (very slowly). This was before I did the research and did no prep on the pipe I was capping off. It was a radiator pipe, painted and cut off with a jagged hacksaw. I proceeded to put the push fit on and it weeped when the system was under pressure. Considering how bad the condition the pipe was, I’m impressed on reflection!
- Remove olive if needed. This is the circular sleeve that compression fittings clamp onto to make a water tight seal.
- Remove all paint and dirt. Using an abrasive sanding mesh makes light work of this and brings the copper back to its original shine!
- Cut the end neat. Dedicated pipe cutters guarantees a clean cut, especially for someone like myself who hasn’t had much exposure to plumbing.
- Deburr! Using a pipe cutter will give a slight lip to any cuts you make. It’s important to deburr them so you have smooth ridges. The reason for this is that the sharp edge would add friction to the water rushing through it. This can create static electricity but also develop pinholes from the inside of the pipe. It goes without saying why you would want to avoid this!
Parts for drain off point
I was working from a 15mm pipe. To add a stop cock this meant I would need a push fit coupler. I went with the Hep2O brand but they are all as good as each other in my opinion. On the end of the coupler I then added a wrench adjustable turn valve. It has a spout at the end which meant I could add a hose when necessary.
I went with the wrench adjustable one as I wouldn’t want a big tap build which may be turned accidentally by anyone not familiar with the setup!
And that’s it. I have a drain point that’s not connected to any radiator and at the lowest point above the floorboards. It’s not something that I intend to use often but will make maintenance and modifications easier down the line! This would be the first step in order to upgrade the radiators.
Whilst its drained you should consider some other upgrades
Like adding a magnetic filter!
