how can i run two showers the electric shower we have at the moment goes of or cold when the washing machine is on or if a tap gets turned on we have a combi boiler

hi. Sounds like you have a cold water pressure problem, make sure your main stopcock inside and outside is fully open. if they are then contact your water supplier to check pressure is adequate. Ray

It is all to do with mains water pressure, clearly if the washing machine or another tap is used this could be enough have your electric shower play up. Kind regards, Mario The Plumber

hi , your shower is cutting out because your mains water pressure is too low i agree with ray on diagnostics and who to contact. once your mains pressure is back you can then run 2 electric showers, or run a shower mixer but you will need an equal pressure valve installed because of your combi boiler . hope this helps . regards paul