hot water violent surges

My new electric water heater was installed 8 months ago, the first time i turned the taps on the hot water came out in violent spurting , hissing and steam. The plumbing store then told me i should turn all the hot water taps on at once. This stopped the spurting but i think it loosened the pipes causing them to clunk abit when i turn the taps on.

However i am often away for a couple of weeks at a time and when i return i have to go through the pattern of turning all the taps on at once otherwise i get the spurting or what might be pressure build up

Im wondering if the electric heater has a pressure build up problem.
I am on city mains water
the water heater is a twin element model. The top element only operates during periods of high demand. Only one unit operates at a time.
I have tried releasing the temperature relief valve as it should be released every six months..
Any help would be appreciated.
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This problem didn't occur with the old heater?
Do you have a PRV (pressure reducing valve) and an expansion tank?

Have you tried turning the water temperature down?

You should be able to hold your hand under a hot tap without it hurting and without the addition of cold water.

It does sound like a stat is set to high or is in need of replacement because it is bad or possibly not flush with the tank. You should check the temp of the water...

surges

It is not a water heater problem, it is a "water" problem. For some reason your water has a lot of entrained air in it, and when it stays in the tank for a long period, and heating it may exacerbate the problem, the air settles out of the water and rises to the top of the tank where the first usage draws it to the faucet causing the same spurting that occurred the first time you opened the faucet when the tank was full of air.

a follow up of hot water spurting problem

Thank you all for your suggestions.
The problem is now sorted. Apparently the wrong sacrificial anode was installed in the hot water cylinder. When the correct one was installed the water stopped spurting. The old anode was almost severed with rust near the top of the rod.
Thank you all again and sorry i didnt get back sooner.
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