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General Plumbing and Gasfitting Talk => Ask Plumbers (Public) => Plumbing => Q & A - Hot Water Cylinders => Topic started by: Wigglywormnz on February 28, 2011, 07:23:12 PM

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Title: Constant dripping in overflow pipe on Hot Water Cylinder
Post by: Wigglywormnz on February 28, 2011, 07:23:12 PM

Im sure that the Hot water cylender never did this when we moved in ~1yr ago. Noticed it a few days ago and just wondering if i can get rough estimate/quote/ideas on what causes this to suddenly happen.

The HWS itself is fairly old...however i am told by last owner element replaced ~2-3yrs ago.

It is a rheem alpha low pressure A180TELHSE. In the picture, the black overflow(?) thing at top right of picture, u can see it drip every 2seconds. Which results it a drip outside the house, every 2secsonds. Pipe goes down into garage, straight across and then out side of house so drains below level of HWS (im sure ive seen alot with pipe out top of roof) why would it now just decide to drip all the time? How do i fix, or how much does it generally cost? kinda just pissing $ in water with that drip 24/7

ANY help much appreciated

Title: Re: Constant dripping in overflow pipe on Hot Water Cylinder
Post by: Wigglywormnz on February 28, 2011, 07:25:37 PM

Oh  forgot to say... water coming thru that gap is fairly hot water... i have changed thermostat down to 60ish.. (was set around 65 or so)  even with power off to it for 15mins drips remain the same if that helps diagnose

Title: Re: Constant dripping in overflow pipe on Hot Water Cylinder
Post by: hefzibah on February 28, 2011, 08:09:16 PM

hi wigglywormnz,

Best call a certifying plumber, they will sort it out............................................

Title: Re: Constant dripping in overflow pipe on Hot Water Cylinder
Post by: Plumber on February 28, 2011, 08:43:50 PM

Hi wigglywormnz,

thanks for your inquiry. First of all you shouldn't play around with the thermostat setting. It should remain at the original setting to prevent growth of bacteria in the tank.

the dripping is most likely caused by a faulty thermostat (a sparky can replace that as well). Basically its getting a wrong temperature reading and hence not switching off the element. This results in the water overheating and the high temperature  activates the valve.

That's one theory, the other one is simply a faulty TPR (pressure relief valve) that needs to be replaced. Best way to go is to contact a local plumber to investigate the issue properly.

hope this helps.

Plumber