Replacement timer control advice for Ideal Isar boiler

9 Jan 2012
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United Kingdom

I wish to replace the basic timer attached to my Ideal Isar HE24 (or HE35, not sure which) Combi with a timer/room thermostat, preferably with a wireless model. Current timer is a basic Drayton LP timer.

Obviously I would like to spend the minimum possible on a new wireless timer room thermostat without buying junk. They seem to vary greatly on price.

My questions are:

Would it be a simple case of swapping the old timer for a new timer/thermostat using the existing 3 core cable which comes from the boiler to the timer or would additional wiring at the boiler end be required? Or would this vary depending on chosen model?

Can I use any timer/thermostat or will some be incompatible?

Do you have any recommendations? My basic requirements are for a wireless thermostat I can fix in a different room to the boiler with standard 5/2 timer controls. Frost protection would be nice too.

Many thanks for any advice in advance.

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Honeywell CM727 (or the CM927 if you decide you want something a bit better, it's arguably an easier product to use and looks better too, the CM927 would be my choice) and a Honeywell Frost Protection Kit K42008628-001.

It should be a straight swap in theory, but there is always the possibility you have odd wiring!

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