We recently had a blocked drain that required sluicing copious amounts of water through it (as well as a bit of poking with a sharp stick) in order to unblock it. No problemo. Unfortunately the copious water sluicing drained our water tank in the attic.
What does this mean? Well you get airlocks in the pipe system. Airlocks mean no water. A bubble of air sits in the pipe between the tap and the tank and blocks the water getting through. So you need to get rid of the air. God bless Google, lets just whack in “plumbing airlocks” into Google and get lots of hits.
The basic theory is you use the pressure in the working tap to force the airlock out of the the blocked tap. Requires pipes and jubilee clips, basically you need to have been a plumber once.
However nobody seems to get airlocks in mixer taps. Well I had a brainwave tonight. So as indicated in the picture attach a balloon to the tap. Then;
- Open the airlocked tap
- Open the tap with water flowing
- Let the balloon fill
- Close the tap with water flowing
- Now with the airlocked tap still open, squeeze the balloon to allow the water to force the air out
- Rinse and repeat until the balloon starts to fill because water has started to flow
Sorted.
A few hundred quid in plumbing fees saved and me with a big shit-eating DIY grin on my face.
Copacetic 
Had a similar problem once and had a cure similar to your own, but no balloon.
1. Open the airlocked tap.
2. Block the opening at the end of the tap with my palm, wrapped in a towel to stop spray.
3. Open the functioning tap.
Depending on pressure and the size of the air lock, should be sorted in a few minutes. Just be careful if your functioning tap is the Hot one and the water is scalding.
(BTW, refreshing to see such a post in my reader this morning, a nice change from hi-tech).
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Hi Ant, Thank you for your suggestion of airlock in mixer taps. I am 59yr old woman and just came back from holidays to find no cold water feed in bathroom. Your solution is brilliant and has saved me a lot of time and money getting a plumber in,
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Thanks for your much appreciated assistance. I’m such a grumpy geeza without a hot morning shower.
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Simple but effective solution. Its nice to see such innovation still goes on. AT least ill know what to do if i encounter the same problem. Hopefully i won’t need to but…
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Well done Joe. Good diy work…
Conor.
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Tried blocking the tap as Ant said- Worked a treat, going out to have a pint on the money I saved on a plumber!!! Thanks lads, Shane
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Have no idea how I came across you post but the balloon idea really is just putting a forced backlow onto the system. Was a great idea though – the plumbers have a hose contraption for this. I am suprised the baloon rim did not squirt out – but good show either way. Also I am going to have to look up the word “sluicing” never heard that one before.
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Hi John,
Yes, you have to hold the rim of the ballon, but its not that hard to do.
Joe.
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Hi Joe, tried this and thought it was a great idea but unfortunately never worked for me as I have a slow trickle of water coming out of the hot water tap so its hard to push the water back up. I’ve tried covering the spout with my hand but water just goes everywhere. Any other ideas?
Helen
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Like the ideas but there is no hot water coming out of any hot water tap so think the air lock is in the tank. The kitchen sink has a mixer tap, (one that lifts and turns). Can I try it with a bathroom tap, the tank is next to the tap?
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Yes I did it with a bathroom tap
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Thanks Joe,
Didn’t have a balloon but thought lets stick the hand on it as suggested above based on the principles above and try and seal it as I switched one tap off and sure enough it fired water off the roof and into my face but now works fine! What a legend I’ve been putting up with struggling to brush my teeth for the past two weeks! I don’t have a tank but my water is off a combi boiler. The mixer stopped working after I scrubbed the bottom of the tap when cleaning and scrubbing the basin! It’s so great when you fix it yourself given your tips!
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Had airlock in bathroom after draining tank for plumbing work. Had no hose and car in the garage, so no way of buying one. Did the flannel trick, covering mixer tap. I could actually hear the air bubbles entering the tank in the loft. Did it several times on both sink and bath, all sorted. What a neat trick, thanks so much.
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