I have an old Mira Zest 8.5kW shower which has recently stopped working.
(see http://www.mirashowers.com/onlinecatalog/pdf/p3617_1.pdf for pdf of
I dont want to buy a new/replacement shower as I will shortly (within the
next 6-9 months) be redocorating the bathroom, including a new shower.
The shower is an electric one which has 3 different "power" settings; Cold,
Medium and Hot.
If I turn the power on via the pull cord, the light on the pull cord
switches on - showing that electric is getting to the pull cord.
Now, if I turn the shower on with the power setting set to Cold, the red
light stays on. Note that the first setting, Cold, can be obtained without
electrical power (quoted from the manual).
If I now turn the shower up to either Medium or Hot the red light on the
Pull cord switches off, and I get no hot water.
Now, if I turn the water supply off and leave the electrical supply on, the
light on the pull cord always stays on, no matter what the power setting is
set to (i.e. Cold, Medium or Hot).
This leads me to believe that the Microswitches inside the shower are
working fine (otherwise I would expect the light on the pull cord to turn
off regardless of whether the water supply was on or off), and that the
fault is either the thermal switch, or the heater tank. It appears that the
fault only occurs when the shower actually attempts to heat the water it is
So, my question is (finally!), how can I test if the fault is in the thermal
switch, or the heater tank - bearing in mind that I am not advanced in fault
finding, but do not mind trying! Obviously, I dont want to turn the
electric and water supplies on and then stand in the shower with the case
off, trying to fault find with the multimeter... That sounds rather stupid!
Thanks in advance,