pressure water system

I am having some trouble with my pressure water system and after some guidance.
I'm not sure if this is the normal way to plumb a system but the water on the pressure side comes out to a T piece one line goes to the cold the other goes to the hot water tank. I can run the shower continuesly when it's cold no problem but when the water is hot the cb keeps tripping. I have noticed when the water is hot i also get a lot of hot water from the cold tap got about 30 seconds.
So I am getting back flow from the hot water. Should I replce the pressure pump? Will this fix it? There is usually pressure in the system when we turn the pump off and close the taps when the water heats in the hot water tank could the extra pressure from the heated water expanding caused damage to the pump? It's got me why it will pump ok when the water is cold but trips the cb when it's hot water?

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HG02 said...
do you have a check valve in the system number 11 in the diagram below its at the cold water inlet at the hot water system

Hi HGO2 I am not sure I will have to check next time I am on board but i dont think there is one but it may be under the floor somewhere or is it supposed to be right next to the hot water tank?
I also don't appear to have number 7 I just have the pressure pump I think.

at the entrance of the hot water tank i guess it stops hot water back flow

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twodogs1969 said...
Ok I am pretty sure it has not got one I understand how this would stop the back flow issue but would this also solve the cb tripping ?

dont think do id be checking the pump current draw and the circuits and earth