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Electrical

3 wire Elkay timer but 3 core wires

Anonymous user 1 March 2024 - 2.57 PM

I have bought an Elkay timer (3875A-1 3-wire) switch from Screwfix to replace the existing switch that turns our Megaflow ECO water heater cylinder on and off. The existing wiring is a pair of 3 core cables coming from the fusebox (red, black, green/yellow) and going to the cylinder (blue, brown, green/yellow) but the new timer has only 3 terminals, 2 Live (L-in & L-out) and one Neutral, and no earth connectors. So I've got 6 wires but only 3 terminals to use. I assume that the live wire from the fuse box cable (red) and the live wire from the water cylinder cable (brown) go into the 2 'L' connectors in the timer switch. This leaves a single 'N' connector in the switch but do I attach the neutral wire from the fusebox cable or the one from the water cylinder cable? Also what do I do with the unused earth wires and the single leftover neutral wire? Many thanks

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4 Answers

Anonymous user

With all due respect this needs an electrician. Heating is complex and if not done right can be very dangerous.
Answered18 January 2022
1
MC Property Services

No reviews yet

Scarborough
Cable from your fuse board (red) goes into the live in connection. The cable from your water heater (brown) goes into the live out connection. Both neutral want to be connected into your neutral connection and connect both earths into a connector block Assuming I read this correctly this will allow you to press your elkay timer switch and power up your heating for a set time according to what you set your dil switches to.
Answered18 January 2022
0
Anything Electrical (London) LTD
Rating: 5 out of 5551 review
Epsom
Hi. You are correct in terms of the live cores, they will go in the incoming and outgoing L terminals respectively. The neutrals go together in the singular N terminal, and the earths must be connected together using a piece of block or wago connector. Ensure the supply to the circuit is properly isolated before working on it
Answered18 January 2022
0
Horace Cliff
Rating: 4.9 out of 54.9536 reviews
Tredegar
There's not enough information to give acurate answer. Are the 3 core wires red , black, green/ yellow or Red, Blue, Yellow. It could be a 3 phase circuit, which is unlikley. Or the old switch has neutral terminal and new one dosent. I think your best to get an electrician to take a look
Answered18 January 2022
0