Open the lid for the batteries and you will see the latch in the battery compartment.
Over the past day or two I've got a new Evohome system up and running for control of my radiators. I'm now turning my attention to the installation of the Evohome Hot Water Kit.
One problem has arisen in the early stages of this process. I want to connect the two-wire cable from the cylinder thermostat to the back of the CS92 transceiver, but I'm struggling to separate the two halves of the transceiver to expose the terminal screws. I've already tried levering it open fairly robustly with a screwdriver, but I'm in danger of causing irreparable damage.
Is there a trick to do this without breaking the box? The attached photos might help someone describe the required procedure.
Last edited by haggis999; 9th January 2022 at 10:26 PM.
Open the lid for the batteries and you will see the latch in the battery compartment.
If I remove the batteries, I can see what looks like a pair of latches, but I've not yet succeeded in opening the case. Does it require a degree of force to release those latches?
With one hand holding the unit and the other holding a screwdriver, I can only prise open one latch at a time, but when I do this nothing seems to happen. The two halves of the case stay firmly attached to each other.
Last edited by haggis999; 10th January 2022 at 11:08 AM.
After many attempts using a flat-bladed screwdriver and a fair degree of downwards force, I finally managed to make one latch stay in the open position while I moved the screwdriver to the other latch. I was then able to open the case.
I don't know if I had a particularly tight example of these latches or if it's just a bad design. Either way, it's been a very frustrating and time-wasting experience!
My next question relates to the location of the CS92 transceiver. I am required to mount it at least 30cm from the cylinder but the cable is not long enough for me to avoid mounting it right beside a 22mm copper pipe. Is that likely to cause any RF connectivity issues, and if so, is it permitted to extend the cable from the CS92 sensor?
Honeywell can be quite anal about that, personally I would stick it wherever it is convenient using blu-tac or sticky pads - if it works reliably then drill the holes and mount it properly, if it doesn't work then move it elsewhere and keep trying until you find somewhere it work.
I've just left mine laying on the floor right next to the cylinder, and it works fine. I had meant to fix it to the wall when I was happy it was working, but never got round to it. And if it isn't broken....
It really depends on distance to controller, building construction etc. whether that 30cm will matter.
My 2 BDRS and CS92 are nowhere near 30cm apart or from metal objects. It just isn’t realistic in my airing cupboard. They work perfectly fine.
This may not be the case in every installation of this manner and if something does go wrong it will be one of the first things people ask so you take that risk.
I’d give it a go with sticky pads as suggested and if it doesn’t work then move it
It looks like no one has any experience of extending the cable, which I fear would affect the sensor signal, so I'll take the advice to just experiment with the location of my CS92 transceiver.
My heating BDR91 is currently just lying on the floor outside my airing cupboard. When I install the hot water BDR91, I was aiming to mount both BDRs on the external wall of my airing cupboard. Apart from making the 30cm spacing easy, I thought it might be useful to have an easily visible indication of when each BDR is switched on. Does anyone else find that useful or do you all just hide them away?