Electric Shower Question

[allgonepetetong]

Chaps

When using the electric shower, should the washing machine fill, a toilet flush or basically any demand in the house for cold water the temperature on the electric shower shoots up until the extra demand stops and then it will return to it's previous temp..

Is this syptomatic of poor flow from the water main into my house?

I'm looking to replace the current combi with a mains pressure heat store system and think I need to replace the water main to the property.

Am I correct?

[allgonepetetong]

Thanks for your replies.

I'll take a look at the batch mixer tap tonight and see what happens when additional demand for cold water is placed abd report back.

thanks again