Best batteries?

[mattyfez]

So turns out I already had this thread in my brain and ended up buying Duracell Optimums in November 2022. The reason I thought I had an issue turned out to be something else... and all my TRVs are still reporting 100% (seems unlikely?):

Interestingly no one recommended Optimums tho!

Probably not reporting correctly/weird thresholds etc... you'll probably find that one day they will randomly drop from 100% to 20% or even zero.

 

[BUDFORCE]

For low drain usage, you could go for lithium cells. Expensive, mind you.

Yea I agree with this, rechargeables are good for higher drain frequent use stuff.

I have a safe in the loft and a CT clamp on cable in the electricity meter box outside, if either die it's a bit of a pain in the ass, particularly the CT claim as I may not necessarily realise straight away.

Decent lithium cells should go about 10 years on something low drain and they are also a lot more tolerant to cold temperatures.

As you say they are expensive though.