Do I need to keep heating drain valve through airbrick?

[danlightbulb]

Hi,

My house has suspended floors, so all the heating pipework has been done subfloor downstairs, with rising pipework to each radiator.

At the back of the house a drain valve has been installed which has been put through an outdoor airbrick. See picture.

Obviously the fact it's outside means it's a freeze risk. Also it's been poked through an airbrick where I want to put an external step.

Do I need to keep this? Or would I need to keep a drain valve at the lowest point of the heating system? With subfloor pipework, not sure where else I would be able to access it.

Any thoughts appreciated.

 

[cross thread]

You don’t need to keep it but it’s very useful to have a low down drain point

 

[danlightbulb]

You don’t need to keep it but it’s very useful to have a low down drain point

Is this the normal way of doing it? As it's a bit of a bodge isn't it? Is there a better way to do it, as it's definitely in the way for future step.

 

[Harry Bloomfield]

You don’t need to keep it but it’s very useful to have a low down drain point

and very handy to have one outdoors, close to somewhere to drain.

 

[Harry Bloomfield]

Is this the normal way of doing it? As it's a bit of a bodge isn't it? Is there a better way to do it, as it's definitely in the way for future step.

As said, a good place to have one. Could perhaps revise the pipework, and relocate it out of the way of your step?

 

[Madrab]

Is this the normal way of doing it

Its a well used option to route a drain point. Saves having to drill through the wall. They are rarely a freezing risk as they are connected to the CH, so it's ambient temp is normally always higher

They make life a lot easier if the system needs drained and/or flushed-cleaned and allows the lowest point of the system to be drained but there should really be 2, flow and return, as that will only fully drain one side.

 

[danlightbulb]

Is there an alternative solution? What's done in modern houses with buried pipework in the floor?

 

[Madrab]

There would still be 2 drains through the wall, if it was a solid concrete slab with drops to the rads then usually the lowest point would be a the downstairs rad(s) with drain off valves on the rads

 

[danlightbulb]

There would still be 2 drains through the wall, if it was a solid concrete slab with drops to the rads then usually the lowest point would be a the downstairs rad(s) with drain off valves on the rads

I've never seen an arrangement like this in any house before. Are they usually hidden?

 

[denso13]

Are they usually hidden?

Not usually, an external drain off is perfectly normal. And best.

 

[danlightbulb]

Strange I've never seen this before, I've lived in a number of houses and asked around my friends and nobody has this.

I'm still not really understanding what the point of it is. The pipework is all subfloor downstairs and accessing it would require floor covering and floorboards to be lifted. Why would this ever need to be drained fully? It seems to me that it's only ever the rads that might need draining, why not just have a drain valve on each rad like I've seen before.

Anyway, where can I relocate this to so that's it's out of the way? I don't really want to drill a hole below dpc into the floor void after I've just spent several days repointing and making the area completely weatherproof. Do I have to make sure it's the very lowest point on the entire system? I've not access the subfloor in other rooms so I have no idea what route the pipework is taking.

 

[Madrab]

It's CH system piping 1'o'1, a means of completely draining the CH system is a standard that should be implemented as part of any CH system installation. A DPC would usually be ~ 150mm from the ground level and some use the airbricks to avoid compromising the DPC, if the pipework falls below that level. The other point I'd mention though is the airbrick is there for a very good reason and it shouldn't really be blocked by stairs either.

The fact that it isn't drain off in all cases isn't a surprise.

As suggested It allows the system engineer a means of draining the whole system down externally in one go and not farf about at a radiator for an age. It also allows for lower section of pipework to be drained in any repairs were required there. Is it the end of the world if they aren't there - probably not - there are other ways to drain the system down but there wouldn't then be a way to completely drain the lower system and if repairs were needed then the only option may be draining the pipework into the founds.

 

[danlightbulb]

Is it the end of the world if they aren't there - probably not - there are other ways to drain the system down but there wouldn't then be a way to completely drain the lower system and if repairs were needed then the only option may be draining the pipework into the founds.

In this case they have only fitted one drain, not two as a previous poster pointed out. So if the intention was to fully drain the system they've only done half a job.

Draining the system into the subfloor, if it was necessary you'd surely drain as much as possible first off the rads then all you'd have left is the bit of water in the lowest level pipework which you'd put a bucket under surely?


I can kind of understand why this was done in the past but it's not done in modern builds/modern systems is it?

And putting this drain under a door frame, exactly where a person might want a step is just a lack of thought.

I can possibly relocate the drain to the left of where I want the step, but I'd have to drain the whole system to do it.

 

[Harry Bloomfield]

In this case they have only fitted one drain, not two as a previous poster pointed out. So if the intention was to fully drain the system they've only done half a job.

It's 9/10ths of a job, when compared to going round draining radiators individually, then dumping what cannot be got out, under the floor.

Draining the system into the subfloor, if it was necessary you'd surely drain as much as possible first off the rads then all you'd have left is the bit of water in the lowest level pipework which you'd put a bucket under surely?

I can kind of understand why this was done in the past but it's not done in modern builds/modern systems is it?

It is just as valuable an asset now, as then..

I can possibly relocate the drain to the left of where I want the step, but I'd have to drain the whole system to do it.

No need to drain - Freeze the pipe, cut, and add an inline valve. You can then add your hole through the wall, and the last bit of pipe at you leisure.

 

[Why Not Indeed]

add an inline valve

Ie, the valve can be within the thermal envelope of the building, and some normally empty pipe can be the external bit.