Santon Premier Unvented Water Heater Problems

4 Dec 2009
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United Kingdom
My electric water heater is a Santon Tribune Premier TP120E.

When water is heated up to temperature, hot water is exhausted (dumped) out of the heater via the tundish and overflow.

I have replaced all electrical temperature controls and the expansion vessel.

Can anyone help diagnose this problem, and advise which component is failing.
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you will have to get a G3 compliant htg eng/plumber/spark

a component has failed and requires attention.

isolate your appliance from the electrical source, and please get someone in immediately
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The Santon's have no internal air bubble.......and the temp system has 2 safety devices BEFORE tmprv blows......much more likely it is the expansion vessel but i agree OP should call out a competant engineer to be sure
yer teaching yer da tae suck eggs ;)

i was pretty sure there was always 3 safety devices on an unvented

internal air bubble = homeowners diy job

external exp vessel = potential job for me!!!

:LOL: :LOL: :LOL: ;)
ask big Alex and wee Barry for a hand out

Big Ek will see yeez right ;) ;)

take it yer a blue :?:
If expansion vessel faulty HW will expand back down cold which will open expansion valve releasing cold water. OP said hot water which is temperature relief so more sinister, best do as GG suggests.
Wolves....for my sins.

And i meant 3 with the tmprv......and it's easy to check if Tibbot is correct.......hw will be way over 60 degrees.

OP is your hot water too hot??

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