I want to replace my combi gas boiler

First thing is check your fuse board can take the load, a competent electrician should be able to advise. You will be able to use vented/unvented hot water cylinder for your stored hot water, and radiators if you wish. You cannot have a combi electric boiler.

you can have electric combi boilers,such as mattira combi central heating boiler,3kw to 15kw,3kw to 12kw on single phase ,3kw to 15kw on 3 phase,12 ltrs/min flow rate from internal storage vessel provdes instant hot water,just like gas combi ,pump, expansion vessel,aav, all inside boiler casing.they also do system boilers.

Brenda as an Electrician I am not an expert on Boilers - Electric or Gas - you need a heating engineer preferably one with experience and knowledge of Electric Boilers and combi boilers. There maybe requirements thereafter on your electrical installation that may need checking.

Unfortunately domestic premises don’t have or need a 3 phase electric supply. Generally a standard domestic premises will be covered by an 80 amp barrel fuse. One KW is approxmetly 4 to 5 amps this should help to work out your electricial load. Your water heater is running at almost 3 KW to give you a rough idea of how much your electric boiler be using.

There are electric combi boilers in existence,recently sourced 3 for a client. Can’t paste a link here,so look for Heatrae Sadia-Amptec and Electromax.

First thing to check is which kind of electric supply you have e.g., economy 7 or HTHC as well as domestic tariff. This means that you would have a dual meter with dual reading. I must ask the question why would you be wanting rid of the combi boiler as this is most likely to be cheaper to run than an electric boiler. Electric boilers are usually installed where there is no gas or oil tank facility within the boundaries of your property. I have experience of installing these boilers and there are facts to take into consideration i.e., if you have an electric shower then you would NOT be able to run the electric boiler & shower together because the Hydro Electric power supply would not be able to withstand it and thus would blow your main fuse from the supplier. This means that load shedding relays require to be wired into the circuitry. The radiators that you have would stay in place as the electric boiler works on a wet system as a direct replacement for a gas or oil boiler. You would definitely not want to run this electric boiler on a normal domestic electric tariff as this would be very very expensive. The minimum power rating of these electric boilers is 6kW ranging up to 12kW. The last job where I fitted these, we required 2 x 9kW boilers in parallel and there would still require to be plumbing pipework modifications to suit your radiator system working on the electric boiler.