On Tue, 16 Dec 2008 21:58:27 -0800 (PST), Matty F
wrote:



I don't really understand where the air would collect, since I imagine
the pipes are reasonably straight, and a 10 foot head of water should
surely push the air out. Without digging up the pipes covered in 50
year old tree roots I can't be sure what's there.
I would expect the air to rise up to the taps, but apparently not.
Does anyone know what was happening?

Hi, unfortunately, no I don't, but similar problem yesterday.

How do these air locks come about and how do they cause flow problems?
Yesterday, our mains water flow decreased to a trickle. Usually, this
is due to a significant leak somewhere in the mains....we are on quite
an elevated site and many miles from the resevoir which feeds us and
there isn't much of a grid! Hence, any significant leak in about a 5
mile radius impacts us. So, rang the water company, fully expecting to
be told "there is a leak at xxxxxx. Is this likely to affect you?" and
they knew of nothing in the area. I'd already checked that our supply
pipe (which is about 200m long) was not leaking by checking the meter.
The CS person suggested turning the house stop tap off and on again
several times which I duly did and voila back to full flow rate. Now I
am puzzled why this worked and how the air lock arose in the first
place. There has been no recent work on any of the plumbing.

Any explanation appreciated.
Please reply to group - email address is not monitored
Ian