Hot Water - What's this bit?

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LesF

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#1576053 17-Jun-2016 22:41

My previous house, about 25 years old, had a overflow valve which no plumber ever seemed to be able to prevent from dripping.

This came out the side of the house, not on the roof. After they all failed to stop the drip I planted capsicums under it. They seemed to do well.

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Les

richms

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#1576055 17-Jun-2016 22:47

Expansion valves are supposed to drip as the cylinder heats up, as that is how it stops the tank from blowing up as the water expands.

Richard rich.ms

Aredwood

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#1576176 18-Jun-2016 12:08

@rendezvous in your second photo, in the left side of the metal tray the cylinder sits in, you can see 2 copper pipes discharging into it's drainage outlet. Check which one is dripping. If it is the one coming from the TPR valve (relief valve at top of cylinder) then replace relief valve. If it is the bottom valve, check if it is thermal expansion - drip caused by water expanding when element is heating the cylinder. Switch power off to cylinder and see if drip stops. If not then either faulty expansion valve or another fault causing pressure in cylinder to be too high - often a failed limiting valve.

Normal amount of water discharged from the expansion valve is approx 1% of your hot water usage. So makes virtually no difference to running costs.

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