failed overnight heating with Horstmann E7 water heater control?

water only heats tepid day or night so I am waiting in desperation on my plumber to sort this as he previously replaced both elements but no real heat,,,,,,,,,,,,,,,help help

Amanda
November 2009

my brother used to have the same economy 7 system.
the lower element needs replacement.for sure. get a qualified person to isolate electrical supply & disconnect both immersion heaters .
to know for sure if it has gone simply check spade connections of element with a volt meter on each conection to see if it has any resistance on ohms setting if no resistance then . gone. carry out these test only when power isolated or disconnected.

gary
April 2009

as john says but it could also be either the overheat cut out or thermostat. Ensure electric is off remove bottom immersion heater cover and check connections are clean and tight if not that then smell if fishy replace themostat. REMEMBER ELECTRIC KILLS IF YOU DONT KNOW WHAT YOUR DOING DO NOT DO IT

ALAN
April 2009

You probably have two imersion heater elements. the boost one is Ok the mian one has failed. You will meed to replace the main one. Lower one in tank or longer one if both at top of tank

JohnL
April 2009