The Efficient Home Forum

Hi All,
I wonder if anyone can advise me at all.
I have had an Evohome system installed for around 2/3 years now, its with Wifi enabled controller, driving 9 radiator/zones all with HR92's I have a standard boiler with tank so also have the controlers for Hot Water with the tank thermostat and Central Heating.

All has been perfectly fine for the last 3 years or so, I have come home from work today and I have 4 zones that are all reporting that they have comms faults either with the sensor or the actuator.
Also the stored hot water sensor is showing a fault, as is the actuator for the Central Heating and the Hot Water.

Both of the devices that control the Hot Water and Central Heating 3 way valve are also showing a RED led.

Does anyone have any idea what the problem could be.

I have ensured I have change the batteries in the devices when any alerts have been seen on the HR92 Radiator controllers, I have never seen any messages about changing the batteries on the 3 way valve controllers or the Hot Water thermostat.

If feels a bit like something has caused this, possibly a firmware update or something.

I didnt install this, I had someone install this for me a while ago, but they dont seem to be able to advise or help in this instance.
Any pointers would be greatly appreciated.
Cheers

Replace the batteries in the CS92A and this issue should cease...

Replacing the batteries in the Hot Water Tank Thermostat fixed the problem. Cheers!

robsonalan wrote:Replacing the batteries in the Hot Water Tank Thermostat fixed the problem. Cheers!

No problem!

I have had similar random error messages relating to batteries in the TRVs and also red lights on the BDR91s. The BDR91 were actually closer than the recommended 30cm so I have moved them apart and replaced them as well but this did not resolve the problem.

I cannot remember replacing the batteries in the hot water sensor but am puzzled how that could effect the BDR91s?

IanM wrote:I have had similar random error messages relating to batteries in the TRVs and also red lights on the BDR91s. The BDR91 were actually closer than the recommended 30cm so I have moved them apart and replaced them as well but this did not resolve the problem.

I cannot remember replacing the batteries in the hot water sensor but am puzzled how that could effect the BDR91s?

When the batteries in the CS92A or the DTS92E get critically low, they have a horrible habit of transmitting 868MHz which screens all the device on the system. The key is to change the batteries in the CS92A or DTS92E annually.

Is there a permanent fix to this issue, for example a software update or upgraded sensor. I like the Evohome for lots of reasons but this flaw undermines the product as it means if the battery is low in the hot water sensor I loose DHW and or CH. Which if I am away and my wife is here on her own is annoying. (It did it again with a relatively new but likely faulty Duracell battery.)

The hot water sensor does not send a low battery fault or even have a light or anything. It just lurks there and when the batteries go flat creates random unrelated faults that are impossible to diagnose.

IanM wrote:Is there a permanent fix to this issue, for example a software update or upgraded sensor. I like the Evohome for lots of reasons but this flaw undermines the product as it means if the battery is low in the hot water sensor I loose DHW and or CH. Which if I am away and my wife is here on her own is annoying. (It did it again with a relatively new but likely faulty Duracell battery.)

The hot water sensor does not send a low battery fault or even have a light or anything. It just lurks there and when the batteries go flat creates random unrelated faults that are impossible to diagnose.

No that I know of. Just set a reminder to change the batteries annually.

The EVOHOME Shop wrote:Replace the batteries in the CS92A and this issue should cease...

This worked for me too, many thanks.
Looking at the log there was just a single low battery message for the CS92A. Both relays near the CS92A were showing red lights and of course no temperature showing for the hot water (along with most of the radiators).
Once I replaced the batteries, things started to improve (presumably as the radio jamming stopped) although it took a while for the actual Hot Water temperature to re-appear on the controller.
Amazing how batteries on a single item like that can disable the entire system - anyone who isn't technical would probably end up paying a large sum of money to a specialist plumber to get it fixed and be without heating & hot water for a period - the wonders of automation!

Robin

This morning I had exclaimation marks against every zone in my system, with no temperature values. The Fault Log was full of COMMS FAULT entries. No obvious root cause.

This article pointed to a potential fix. Replace the batteries in the Hot Water Tank Sensor.

I checked the battery voltage which at 1.345VDC each was clearly below niminal and replaced them with fresh batteries. This led to the Hot Water Temperature being reported and then the various other sensors started to report values. Over time, the Fault Log captured SENSOR RESTORE for each sensor in the system. The Fault Log also captured ACTUATOR RESTORE for each actuator in the system. Finally, normal operation, Hot Water and Zonal Control was restored.

Result!

Thank you Richard!