Ask an expert

Get free help from our community of tradespeople

Redding water heater

Posted by rob hemsworth, on
Wat size cable do I need to wire a . kW water heater
David West

David West

Hi Rob It depends on what Wattage the water heater is. If its a standard 3KW heater (Similar to immersion heaters) then it will need a 2.5mm cable. This however needs to be run off its own circuit from the consumer unit using a 16 Amp breaker and connected via a 20 Amp rated switch. If it is a higher Wattage...say 7KW, then you will need something more robust! A 6mm cable will be needed and up to a 32 Amp breaker. Again on its own circuit connected via a 45A Cooker type switch. Kind regards Dave ADW Domestic Electrical
Bogdan Banasiewicz

Bogdan Banasiewicz

Hi . If you use 3 kW water heater ( standard power ) and length is up to 1,5 - 2 m size is 1.5 mm but I recommend 2.5 mm. regards Bogdan Banasiewicz PROTON

What would you like to do now?

Find more questions Create my Job

Homeowner stories

Homeowner stories - Nick

Nick shares his story of finding local tradespeople in his new area.


Get our app for homeowners

  • Send messages and get notifications from tradespeople
  • Add photos to get more accurate quotes
  • View tradespeople’s profiles