Originally Posted By: LittleBlueThing
One thing to consider with 'instant' heaters is the max hot water flow rate. ie ambient +X degC litres/minute.

The main problem is that to run a decent shower or fill a bath in a reasonable time you need many kW of heat to be transferred into the flowing water to raise the temperature. In the UK you'll typically be limited to about 3kW for an electric unit.

In the winter this equates to a lukewarm trickle from the shower wink



I didn't even think of that thanks. I know they use a lot of electric when running so I figured the water temperature wasn't an issue.

Hopefully the manufactures list the "X" heating factor in your equation so I can tell what I'll get.

The house is wired for 200 amps. I'll have to do some adding to see if I'll be popping breakers.