Economy shower timer issue (off peak electricity timers)

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The off peak fuseboards will have power, if my eyes are working that's the 3 smaller ones above the normal rate one.
According to the instruction book:

The OFF PEAK neon will illuminate when the immersion heater is activated

The BOOST neon will illuminate when the Boost timer is in use.

Also, if you look at your electricity meter, the flashing light will flash faster when the extra power is being used.

As far as I can see, if the neon is on, but the water is not being heated, you have a fault as we postulated earlier.
The OFF PEAK neon will illuminate when the immersion heater is activated
According to the picture you posted, it is different and that neon indicates it is set to 'timed'.

As far as I can see, if the neon is on, but the water is not being heated, you have a fault as we postulated earlier.
Depends on the timer.


Set the timer to whatever time the meter shows and you will get the seven hours even if the meter is wrong.
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By my reading of the instructions, if the "timed" neon is on, it should supplying the lower immersion. If the "water heater off/timed" switch is moved to "off," I'd expect the "timed" neon to go out and (provided the lower immersion is working) the flashing light on the electricity meter should flash more slowly because the current reduces. The Horstmann timeclock has a 5-day reserve battery and continues to receive power even if water heater is set to "off"

According to the installation guide, the timeclock tappets are inside the cover and not adjustable from outside by the user.

Annoyingly, although the docref is the model shown, the picture seems to be of an earlier model. The document refers to "Regional Electricity Company" so is about 20 years out of date.

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I haven't found instructions that show a timer like your picture - the same as Katy's - so don't know if they are the same.
No, you're right.

TLC sell the later timer, and have that photo, but their library documents have the older picture, as does the Horstmann website.

Most likely it is the same mechanism.

The product name seems the same.

the installation instructions
show only one Live supply, which fulfils both the off-peak and the Boost elements.

So probably it comes from the newer (peak rate) CU, and not one of the switchfuses on the Meter Timeclock, though the wiring in that cupboard is rather ramshackle.

The Horstmann Timeswitch mechanism cuts supply to the Boost switch during Timed periods.
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Looking at the photo in Katy Dibbern, Yesterday at 6:19 PM
the Timed neon is on. This makes me believe that the Horstmann would have been trying to energise the lower element; and if there is little hot water, there is a fault on it.

Perhaps the Boost still works (outside the Timed period).
My first port of call would be the immersion(s) , check thermostats, safety trips ( if fitted) , and elements, for this you will need some electrical knowledge and test equipment, if all ok move on to the timer and test the outputs
decided to wait for the landlord to get someone to sort it... i clearly dont have a clue what im on about... n thanks to everyone whos replyed!!!! But still all confusing haha.. Fingers crossed it wont take him the 3 months when it broke befofre!!! thanks everyone xxxx merry xmas xxxx
I deduce that it didn't heat up overnight, so for one of various possible reasons, the bottom element isn't working.

Put the "boost" knob on during the day (it won't work during the hours the "timed" period is set).

Note that the knob is turned ANTI-clockwise, as shown on the arrow.

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