Isar he35 wiring

10 Feb 2017
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United Kingdom
Hi there.
I'm a new member so hello everyone !!I had an isar he35 combi boiler fitted a couple of years ago, and the guy who installed it very kindly chopped offresh the original connector. Does anybody know what colour the L1 L2 and L3 wires are as I cannot find a wiring diagram anywhere on the Web. Any help would be greatly appreciated (the wiring is currently connected to mains via a connector strip)

Many thanks
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Hi John and welcome to the forum

Unfortunately, the wiring you refer to doesn't come with the boiler, so the colours of the wires used for the installation would have been selected based on the personal preferences of the installer. So you will have to follow them to see where they originate from.

L3 is the main live supply from the 3A fused FCU
L1 is the live supply out to the remote controls (Programmer / Thermostat)
L2 is the switched live back from the remote controls (Programmer / Thermostat)

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