Immersion Heater Timer Not Working - Horstmann Electronic 7

[Jay5958]

Hi,

I am quite new to this but need some advice. I live in flat which only uses electricity (Economy 7) and uses an immersion water heater with two elements (top and bottom) to heat water. I have a Horstmann Electronic 7 Water Heater installed which is configured to run an off peak programme between 3am to 7am (Economy 7 off peak times).

I want the water heater to only heat the water during those hours and remain off during the rest of the hours. However, I can hear the elements heating the water constantly and therefore using more electricity.

The timer has two wires coming out of it, one for the top element and one for the bottom element. When the timer is switched to timed, using an electric tester pen I can only see power going to the top element. Why is this?

Is the water heater wiring installed correctly?
Why does it heat during the day?

I have attached images of the following:
1. The water heater specification
2. The wiring coming out from the water heater (2 wires which connect to the top element and bottom element)
3. The wiring of each element (top and bottom)
4. The wiring within the timer

Appreciate any help

Water Heater Specification

Wiring coming to the water heater from timer

Associated colour diagram

Top Heating Element Wiring

Bottom Element Wiring

Timer

Timer Wiring

 

[CBW]

That bottom element has scorching around it, any ideas why? There also appears to be heat damage at the terminal strip. The photo of the Horstmann is no good as this is just a copy from the internet, we need to see yours. You live in a flat, do you have a landlord?

 

[Jay5958]

1. Both elements were replaced a few months ago, the scorching was there prior to the elements being replaced. The electrician saw no evidence of damaged wires so couldn't diagnose why the scorching.

2. I own the flat so no landlord.

3. Attached image of the front of my timer

 

[oldbuffer]

1. Have a read of https://www.gotogasdocs.co.uk/f/m/H...Heating Controls/Electronic 7 Series 3 UM.pdf
2. Try a reset of the controller per the instructions above.
3. It shouldn't heat during the day unless:
3a. It has been wired incorrectly.
3b. The timed booster function has been set.
3c. It occurs during an "allowed" period within the Economy 7 tariff period.
3d. There is a fault in the controller.
4. I personally wouldn't trust a voltage pen. If you have one, can use it, and are comfortable with dealing with high voltage electrics, a multi-meter is a better tool.

 

[Jay5958]

1. Have a read of
2. Try a reset of the controller per the instructions above.
3. It shouldn't heat during the day unless:
3a. It has been wired incorrectly.
3b. The timed booster function has been set.
3c. It occurs during an "allowed" period within the Economy 7 tariff period.
3d. There is a fault in the controller.
4. I personally wouldn't trust a voltage pen. If you have one, can use it, and are comfortable with dealing with high voltage electrics, a multi-meter is a better tool.

SOLVED

Thanks a lot for your help. I ordered a new controller to test it and it has solved the problem. The controller was not switching when required. I realised with the new controller when switching a click could be heard whilst in the old controller no click was heard.