Wet vac to the rescue - again

[The Medway Handyman]

I reckon one of the most useful tools I own is a Wickes/Earlex wet/dry vacuum.

Use it for all sorts, emptying cisterns, unblocking sinks, draining water from rads & in dry mode I can trim doors, worktops etc with a circular saw almost dust free - very useful if working in a third floor flat.

Another use I found today - clearing airlocks in a central heating system.

My CH system is a bugger to bleed, especially the hall rad which is back to back with the lounge rad.

Refilling the system today, nothing coming out of either rad. Removed the bleed screw from the hall rad, held the vac hose firmly against the hole & switched on. Instantly rewarded by a large 'gurgle' sound & a steady stream of water - easily controlled by the vac whilst I replaced the bleed screw.

System bled in minutes with no mess.

Why don't more plumbers carry them?

[newshound]

Couldn't agree more. I'm about to see if mine will start a syphon in 150 metres of 25 mm from a spring to our stables. The little battery bilge pump I tried today wouldn't push over the necessary 8 feet or so.

[YAPH]

Been there, done that. Word of warning though: mine (at least) has a habit of spitting filthy water all round (the customer's) room when it gets full. Slinging a dustsheet loosely over it can help contain that.

[Dave Plowman (News)]

I've got an ancient Rowenta which has a float - rises with the water and eventually blocks the input to the fan and switches off the motor. 'Twas a Which best buy - and they were right about that.

[The Medway Handyman]

Is yours the Wickes/Earlex? It should have a shut off ball & a foam filter. Never had mine spitting stuff around.

[ARWadworth]

Because they charge by the hour?

Adam

[John Stumbles]

Yup. Shut-off ball doesn't cut the motor, just stops it sucking. The foam filter packed up long ago and I now use the corrugated one (like a car air filter). Maybe mine's just an ancient sample and they've fixed it on the newer ones. Trouble is it keeps on going so no excuse to replace it :-)

[The Medway Handyman]

Check the ball & seat to make sure they are clean. The spitting is no good for the motor - it will rust out.

[The Medway Handyman]

In a previous life I was an accredited trainer for The British Institute of Cleaning Science. You would have failed your 'Wet Pick Up' test for not checking the float vavle every time you used the machine :-)

Failing to check the mains lead every time you used the machine would have stopped the test immediately!

Naughty man!

[Andrew]

I have a piece of 15mm foam pip insulation that fits (i) over a 15mm pipe end and (ii) into the end of the flexible pipe. Provides a surprisingly good fit. Used it to remove water from a short U before a radiator tail that needed to solder.

Andrew

[Ian_m]

Also useful for cutting a plastic central heating pipe whilst live, for adding a drain valve. Kitchen fitters fitted a plinth heater but no drain valve. Would be best place for drain as bottom of circuit and near back door get a hose pipe out direct to manhole.

Anyway get new section of pipe ready (with valve on end), get plastic insert ready, get pipe cutter ready, get loads of clothes ready (just in case). Turn on vacuum, cut pipe, finger over end, insert insert, finger over end, push on new peice, hardly a drop spilled, I was quite impressed with my self.....

[The Medway Handyman]

I've done that & got surprisingly wet :-(

[Chewbacca]

I've done similar and I thought 'barely a drop spilt' my good wife said 'you have flooded the corner' actually a lot stronger than that. So it's all in the eye of the beholder........

[Dave Liquorice]

What you all need is a couple of bungs, stuff one in the vent pipe and the other in the header tanks outlet. No air or water can now get in to replace any that leaks out, it really does work.

On a pressurised system I think you'd just need to de-pressurise it, disconnect the filling loop on the supply side (as it always should be any way), direct hose end into bucket open valve until there is no more flow,

*close valve*.

[The Medway Handyman]

Deffo. With a pressureised system I just turn off the filling loop (asuming its open, which it shouldn't be). Hadn't thought of using the filling loop as a pressure drain - good one.

With a tank fed system, I have used the bungs you suggest, but if you turn off all the other rads both ends you have much less water to drain & re filling is much easier.

[Dave Plowman (News)]

It's often the drain point for the boiler itself - but rarely low enough for the whole system.

[Dave Liquorice]

Should also be disconnected as well as turned of I believe...

Never having had or worked ona pressurised system it's the only way I could think of of letting the pressure out. There must be a drain point some where but they aren't normally easy to get at, have a handy bit of hose already attached and a valve that is easy to operate. I did think in passing of letting the air out of the expansion vessel but that probably isn'tr a good idea, might rupture the rubber diaphgram inside and you'd need some means of pumping it back up.

With the bungs in *very* little water comes out unless you have a leak somewhere. Still best to be cautious when cracking open the first joint just in case. I've used the bungs and only about 1/2 a cupful came out, not enough that an old medium hand towel couldn't cope with. If changing a radiator valve it's worth being aware that the radiator might "glug" air in through the open hole and a glug water out...

Tht can be avoided, fit the bungs, turn off both valves on the rad you are working on. See if there is enough slack in the pipe work spring the pipe out of a valve bottom, direct open end of valve into suitable receptical, open valve and open open radiator bleed valve. Radiator will drain into receptical. Once drained remember to close the bleed valve or you might forget later and when you remove the bungs and turn on the valves again.

[Dave Plowman (News)]

The sensible thing is to have one of those combination lockshields and drain valves on a rad close to an outside door. They allow draining down far enough for most jobs - although you might also have one at the actual lowest point, which never seems so convenient. Problem with using the boiler one as a drain point is they are usually not low enough to allow work on ground floor rads.

[YAPH]

Usually: I use this technique a lot but occasionally it doesn't stop off the flow as it should. Sometimes you can pin it down to an automatic air valve (just tighten up the dust cap) but sometimes there's no apparent reason.

I think that works on some Vaillants but on most* systems the required non-return (check) valve is on the primary (CH) side of the filling link rather than on the supply side, so when you open the valve on that side nothing (should) come out.

• IME

[Dave Liquorice]

Ah but the beauty of the bungs or depressurising a system is that you don't have to drain down below the point you are working at. If no air or water can get in then none, or very little, is going to get out. Also means you haven't got to worry about how much inhibitor to add to keep the concentration up etc etc.