Im in the process of draining, cleaning etc the central heating system in my house as its not been done in 10 years+

all of the system is pretty easy to sort, and I have a couple of drain points already but my lounge radiator about 6 foot long and a double, is the furthest away from the boiler, and I believe silted up with gunge, and to drain that side of the house will be a right pita,

however if I was to use a self cutting drain as per the attached ebay item, my problems will be minimized

The question is, how easy are they to work with, and does fitting one into a pipe cause loads of water everywere,
or is there minimal leakage that can be caught in a container ?


https://www.ebay.co.uk/itm/self-cutting-brass-draw-off-drain-cock-valve-15mm-heating-plumbing-copper-pipe/301207145752?_trkparms=ispr%3D1&hash=ite m462158

I personally can't endorse them. Bought one 20 years ago to "make it easy" to fit an outside tap. Cut into the 15mm pipe easy enough, but had a small drip. I tried to back off the tap part so I could wrap some thread tape on, but the centre part blew off the threads blasting water all over the kitchen. Could have just been unfortunate but I will never work on pressurised water pipes again.

Thanks for the reply

My system will be drained to the manifold under the floorboards at the top of the stairs, so all water that would be in the pipe would be around 15 metres of 15mm pipe, so not under pressure like a mains would be

steve

When I have a marine tropical aquarium I used one of those to tap into the cold water system and I must admit while it worked ok and didn't leak , the hole it pierced was very small. If you have cack in the system it might block up, plus you obviously have to cut that section of pipe out when you've finished and replace, or connect it where it can't be seen and hope it doesn't leak ( but you know it will the first day you go on holiday). Surely if you drain the system down there shouldn't be a lot of that evil brown water left in that rad

Shooter

When I flushed my system I connected my hose pipe to a drain point and closed off all radiator valves just leaving one rad open and flushed through. Then closed it and opened another.
If you fit that self taping drain point I think you will be heading into trouble.
Brad

I appreciate your comments

The rad in question is a monster of a rad, and well to heavy for me to lift, it does not have any drain off valves just normal trv and similar the other end

It has two 15mm pipes of about 15 metres one feed and one return, to the rad,
so once the system is drained, this is effectively still full of water/crud like a sump. as the crud has no were to go,

The only drain offs are in the garage, and easy to do, ive done it many times, but the other side of the house does not have any drain offs,

At very worse, I will have to shut both trv and other valve off, crack open the bottom joint and let the rad empty into containers
and once empty open up one valve to flush whats left in there out of the rad, into containers,

I was trying to avoid this, as ive done it before, 20 years ago, and it took about a week of faffing about
and obviously if one drop of water goes on the carpet, im DEAD !!!

ive bought a trv with a drain cock attached, and will fit it once the system is empty, to alleviate this problem in the future


steve

Either pull up the carpet or cover and tape it with heavy plastic. Then have old towels handy to mop up any spillage from the containers or perhaps a wet vac. Or maybe you could syphon the water out from one of the top radiator plugs using a flexible hose?

Personally I would protect the carpet then use a couple of shallow Tupperware tubs and a large bucket and just crack open the joint and drain to the tubs, alternating between them while emptying them into the bucket. Just make sure the bucket is large enough for all the water. You can also stick on some blutak either side of the joint to act as a drip point so avoid the water running too far along the pipes or rad.

quote:

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Originally posted by craig1410
Either pull up the carpet or cover and tape it with heavy plastic. Then have old towels handy to mop up any spillage from the containers or perhaps a wet vac. Or maybe you could syphon the water out from one of the top radiator plugs using a flexible hose?

Personally I would protect the carpet then use a couple of shallow Tupperware tubs and a large bucket and just crack open the joint and drain to the tubs, alternating between them while emptying them into the bucket. Just make sure the bucket is large enough for all the water. You can also stick on some blutak either side of the joint to act as a drip point so avoid the water running too far along the pipes or rad.

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I have two appliance T connectors like these in the bottom of the longest legs of the CH system.

washing machine T
They are compression fittings and so easy to remove a short section of copper and fit them. The washing m/c fitting is 3/4 bsp so will take a regular outdoor hose fitting.

If the pipe is bare the JG Speedifit versions are easy to use and will survive well in even the hottest CH system (circa 65C)
Speedyfit

Fitting either one of these would allow you to run water from the filling loop - if a combi, or from the header tank if an open system and out at the lowest point. By closing all the other rads the water can be encouraged to travel through your sludged up one.

In my experience the best solution is to turn off the valves, undo them from the rad, in so doing drain the rad,. takeaway cartons and buckets required.
Then with the bleed valve closed, lift it from the wall, turn it upside down and carry it outside, then wash clean with a hose.
When refitting a good dose of fernox or equiv will help to keep it sludge free for a long time.

As a check, if the rad takes a long time to heat, is cold at the bottom and bleeds black water then a good flush is in order.


HTH

[Edited on 8/5/20 by HowardB]

Alternative idea.


Drain everything, open the radiator top bleed. Close one valve.. Pump compressed air in to force the water to a different part of the system.

*If* it works you now have a much lighter radiator to take outside and flush.

You also have the chance to change the radiator valve to one with a drain point.

Mike

Im impressed with your ingenious plan, and will think carefully before I try and blow up my central heating system

steve

NB your do this at your own risk. I'm not having any responsibility if it goes wrong (but I insist on pictures)

I think Mike is on to something here - essentially the radiator is a balloon so if you inflate it, the water will be pushed out into the pipework and you can then just close the TRV and lock-shield valve to isolate the now dry radiator. You just need to ensure that you have an open drain valve somewhere in the system to prevent pressurisation of the system as a whole.

Nice one Mike.
(Disclaimer: I'm not a plumber and not responsible if you blow up your central heating system etc etc. )

I have a drinking water tap that runs through a carbon filter that has this sort of pierce the pipe fitting.
As it runs through 1/4" nylon the small hole it makes isn't an issue. Must be about 8 years old now.

If it were me I'd fit a normal drain point before filling the system back up.
It's the old Sods Law thing. If you don't you will need it. If you do, you won't.

Paul G

I'm not a plumber, but Mike's idea sounds feasible.

If you follow this route then pictures are essential!

Our house has a similarly large radiator, but fortunately 2 off lower drain points in the central heating system. 1 by the front door and 1 by the back door.

I'm interested now to see/hear your progress.

So we're all agreed my ideas is good.

Either practically or for a laugh - we're just not sure which.

How old are people properties, my last house built in 1989 and current house built in 2004 both have a drain valve on every radiator. Last house had it radiator side of the valve so you could isolate and drain am individual radiator. Current house has it system side of each radiator.

On my dad's house built 1980ish by a local builder has none. He took some nuts that would hold on a radiator valve to a radiator, cut a bit of rubber to fit inside and then found a coin to fit. Inside. I've cream tubs under the radiator with towels. Turn the radiator off. Undo the valve nut. Quickly get the replacement rubber nut on. Radiator locked off. We then lifted the radiator off and took it outside for a clean. Thinking you could change this to then fit something to the remaining pipework to open the valve and drain the system. Does mean you have to have pipework that allows a bit of bending.

Mine was built in 1879,.. the original plumbing was added in 1968, a real mess, some of the radiators were so far from the boiler that the water had long forgotten what it was doing and was cold anyway.

I have replaced it with short lengths of 22mm pipe from the boiler leading to even shorter lengths of 15mm leading to rads on internal walls.

Some of the original radiators were 40' from the boiler on the end of very convoluted runs of 15mm/ 1/2" pipe with dozens of compression fittings.
It was a profitable trip to the scrappy



[Edited on 9/5/20 by HowardB]

A plumber that worked on my dads c heating used a wet vacuum and sucked the water out a rad he had a adapter to screw into the top of the rad
I didn't see him do it but he was very fast
Jacko

An update to my draining down problem

I did look into some of the ingenious replies, and concluded that most were hair brained and of the dubious manner of being to far fetched

so I hatched a plan, that involved lots of water repellent plastic, a garden planter tray of about 750/750 50 deep, a few plastic containers of differing size, just to make life interesting, !!

So, shut off both radiator valves, and the stop cock on the header tank was turned off

This will only drain the feed and return pipes, not the radiator

drain the whole heating system down on the other side of the house (lots and lots of crappy gunge came out)
This now left me with two pipes of 15mm copper plumbing of around 15 meters to empty
so i cut a small hole into the return pipe under the radiator, with a hacksaw, and let it drip, well flow as the cut was deep
The plastic planter was under the rad to save the carpet, the plastic sheets under that, and the plastic containers used to the move the gunge into a bucket

six buckets of sediment later first pipe was empty

Now, i had to fit an isolating valve into the 15mm return pipe, as i had cut into it, that was empty, and, and make a new connection to the radiator
but with a trv with a drain cock attached, and re fit

Fill the system up, put the heating on to get some flow, and wait

now with the drain cock on the trv, on i was able to drain the rad, and i cannot describe the sh!t that came out, 20/50 oil was easier to pour than the muck that came out

And, you may all ask, why fit an isolating valve in the return pipe ??

Well, and a surprise to me, was that when i shut the isolating valve off, and let the drain off valve flush the radiator out, it was actually a mix of wet grease that came out, it was actually that thick, you could scoop it up in your hand, and it would stay there
!!

we have the heating n at the moment, and i will reflush the system again tomorrow, and probably again over the next few days

All in all, ive cleaned out the heating system im my house, and will replenish it with a cleaner, flush it al out and put a preventative in there

and most of all, after 35 years here, i can drain off the lounge rad, easily

steve

Sentinel X400 is very good at removing any crap in the system
I re-filled ours with some and let it run around for a couple of weeks
Drained down and flushed through and then re-filled with Sentinel X100 to protect the system
The rad's temp's were noticeably better all over the house