Issue with UH8-RF v2

[athlonoc]

Hi,

 

I’m looking for some help / advice to see if there is anything further, I can do.

My property is a newbuild of 2 years and was fitted with the following

 

UH8-RF V2 wiring centre

5 NeoAir v3 stats

 

Connected to Mitsubishi ASHP heating system.

 

All has been fine until the last few days where I noticed I could hear the system was pumping water around and at times, I could see the ASHP was running.

At the same time I noticed the Wiring Centre UH8 was lit up on a specific zone.

When I checked the stats I noticed two of them had battery warning icons up.

 

So, I simply replaced the batteries expecting this to solve the problem. However, things started to go downhill from here.

It became obvious that the pairing was no longer right as I was not able to call for heat with all the stats ( testing purposes ). All stats would have a flame but not all the lights on the UH8 would lights up.

 

So, I reset all five zones after powering down the UH8. I was able to pair successfully 4 of the 5 zones but one wouldn’t pair. So, I used a spare stat to see if that could pair, which eventually it did after several attempts, but then I noticed one or two of the other zones would no longer call for heat.

I then used one of the three spare zones on the UH8 in case zone 5 had developed a fault.

I’m now experiencing intermittent control, when calling for heat.

 

I can manually push any of the zone buttons on the UH8 and they light up.

I have now on three occasions, powered down the UH8, reset the master RF button so it flashes quickly. Then reset all 8 zones so they all flash quickly, then one by one repaired with my 5 Neoair stats. In the past when setting up it worked fine and always paired within 5 to 10 seconds, and all would call for heat.

 

I have replaced all batteries in the stats.

I have reset all the stats.

I have reset the zones on the UH8

 

But I am left with some of the zones not lighting up when the stat is calling for heat.

 

My questions are:

 

Is there anything further I could try?

Is it possible that the RF communication device on the UH8 is now faulty, or the UH8 wiring centre in total.

 

 

No other RF or Wifi devices have recently been installed that might interfere. Certainly not for over a year and everything was working fine until the battery symbol on a couple of the stats were showing and the flow pump in the loft could be heard running.

 

I’d be very grateful for some expert advice.

[MikeSharp01]

30 minutes ago, athlonoc said:

I’d be very grateful for some expert advice.

Are you close to a neighbouring property that might be causing radio interference?

 

I notice that the data sheets on the U8 show a set of engineers DIP switches that can be used to test the zones maybe this could be a way of eliminating some issues although it looks and feels like an RF comms issue doesn't it. Don't attempt an internal playing with power on unless you know what you are doing though. The manual I found here: https://www.theunderfloorheatingstore.com/cdn/shop/files/UH8-RF_V2_Datasheet.pdf?v=16128903087641331176 

[athlonoc]

40 minutes ago, MikeSharp01 said:

Are you close to a neighbouring property that might be causing radio interference?

 

I notice that the data sheets on the U8 show a set of engineers DIP switches that can be used to test the zones maybe this could be a way of eliminating some issues although it looks and feels like an RF comms issue doesn't it. Don't attempt an internal playing with power on unless you know what you are doing though. The manual I found here: https://www.theunderfloorheatingstore.com/cdn/shop/files/UH8-RF_V2_Datasheet.pdf?v=16128903087641331176 

Thanks Mike,

I'm going to assume that no interference from neighbours as I live in a well spaced out area with 8 other houses and all have the same setup. No one else is having this issue and mine has been fine up to this recent point where I had a batter icon on two stats and then noticed things with the system were running when not called for. I think might order a new UH8 centre and then see if the problem still exists. As with so much it will be a process of elimination. 

[JohnMo]

I would leave it alone for a couple of hours and see if it fixes itself.

 

Are you running weather compensation?

 

But some alarm bells

You have ASHP which is great, but your house is zoned and this will mean inefficient running

 

If you need thermostats flow temp is too high.

 

If you have zone it may also mean you have a buffer again driving inefficiency.

[Nickfromwales]

On 05/07/2025 at 12:40, athlonoc said:

Thanks Mike,

I'm going to assume that no interference from neighbours as I live in a well spaced out area with 8 other houses and all have the same setup. No one else is having this issue and mine has been fine up to this recent point where I had a batter icon on two stats and then noticed things with the system were running when not called for. I think might order a new UH8 centre and then see if the problem still exists. As with so much it will be a process of elimination. 

Is the UH8 mounted quite low? I would first try extending the wires and mounting it as high up as is possible. 

[SimonD]

On 05/07/2025 at 11:04, athlonoc said:

Hi,

 

I’m looking for some help / advice to see if there is anything further, I can do.

My property is a newbuild of 2 years and was fitted with the following

 

UH8-RF V2 wiring centre

5 NeoAir v3 stats

 

Connected to Mitsubishi ASHP heating system.

 

All has been fine until the last few days where I noticed I could hear the system was pumping water around and at times, I could see the ASHP was running.

At the same time I noticed the Wiring Centre UH8 was lit up on a specific zone.

When I checked the stats I noticed two of them had battery warning icons up.

 

So, I simply replaced the batteries expecting this to solve the problem. However, things started to go downhill from here.

It became obvious that the pairing was no longer right as I was not able to call for heat with all the stats ( testing purposes ). All stats would have a flame but not all the lights on the UH8 would lights up.

 

So, I reset all five zones after powering down the UH8. I was able to pair successfully 4 of the 5 zones but one wouldn’t pair. So, I used a spare stat to see if that could pair, which eventually it did after several attempts, but then I noticed one or two of the other zones would no longer call for heat.

I then used one of the three spare zones on the UH8 in case zone 5 had developed a fault.

I’m now experiencing intermittent control, when calling for heat.

 

I can manually push any of the zone buttons on the UH8 and they light up.

I have now on three occasions, powered down the UH8, reset the master RF button so it flashes quickly. Then reset all 8 zones so they all flash quickly, then one by one repaired with my 5 Neoair stats. In the past when setting up it worked fine and always paired within 5 to 10 seconds, and all would call for heat.

 

I have replaced all batteries in the stats.

I have reset all the stats.

I have reset the zones on the UH8

 

But I am left with some of the zones not lighting up when the stat is calling for heat.

 

My questions are:

 

Is there anything further I could try?

Is it possible that the RF communication device on the UH8 is now faulty, or the UH8 wiring centre in total.

 

 

No other RF or Wifi devices have recently been installed that might interfere. Certainly not for over a year and everything was working fine until the battery symbol on a couple of the stats were showing and the flow pump in the loft could be heard running.

 

I’d be very grateful for some expert advice.

 

Yup, been there seen it and done it. I've lost a lot of hair in the process. I had a customer's house where the neostats would repeatedly pair fine up until the 10th stat and the last ones would refuse to pair, or would pair and then not work correctly. This was after replacing the wireless hub. I doubt it's the UH8, but more a tendency of the neoair stats. Why they can be problematic, I don't know.

 

When you reset everything, did you proceed to repair from the closest stat to the furthest stat and do this methodically?

 

It's worth calling Heatmiser tech support as they will help you through the process while to try to repair and get everything up and running again.

[Temp]

Google tells me they operate on 868MHz which is also used by some burglar alarms. I don't think having a burglar alarm on the same frequency should cause a problem but I suppose it might be something to check.