Tado V3+ thermastat issues

Hi ​@TayUK 

Did you manage to diagnose the problem?

Hi, thanks for the response. 

It's a standard boiler as far as I am aware, there is an immersion heater tank (I think), I say this as she has 2 thermal panels on the roof and a mass of pipes that frankly have no idea what they do or where they go. 

The gauge on the front of the boiler does not work, it was serviced several weeks ago, the pressure is shown on one of the digital menu’s, currently (or at least 3-4 days ago when I was there) it was showing 1.1-1.3BAR I think. 

I understand that this is a known issue with this boiler model. The plumber mentioned during the service this is a known issue and confirmed the system was pressurised as expected. 

My mum lives in a bungalow and everything is on the ground floor.  The boiler sounds perfect when it's running, as mentioned putting the Tado stuff through its tests (heater button on the receiver) the boiler kicks in after a short delay and the radiators heat up, but this is a temporary thing as the test mode only stays on for a few mins..   

The wifi signal to the back of the house (Where the receiver is) isnt terrific but the receiver seems to respond when manually triggered, there has been times when this has not worked though.  

This morning the heating wasnt working again when I check at 07:45ish, it should have come on as per the schedule below,  you can see even after I managed to get it going (pressing Temp up/down/hot water button on/off - boost rooms etc on the app) briefly,  it changed its mind and stopped again a couple of times, its currently turning on and off as expected at around 23 degs’C 

I have been told that it could be possible to get an offline schedule configured that could mitigate the issues seeing but its a work around as opposed to a fix. 

Currently, its 50/50 as to whether the boiler comes on as per the schedule.

I’m back home down south and no further along the diagnosis trail.  Its made significantly harder not actually being there. 

I presume this is going to be a Tado support issue despite the fact there appears to be some sort of integration with the OVO Energy website?. 

tks

AFAIK, yes. Tado Support would be the best place to ask for help - OVO isn’t responsible for providing support for Tado devices.

To me that does not sound right.

What kind of service does not replace faulty/broken parts?

Is your mum being ripped off by “The plumber”?

Good question, I suspect it might have been particularly expensive part perhaps..

I been thinking a bit more.

Often it isn’t the guage itself that is faulty,.
If the boilers internal expansion vessel has failed (which they can do) then when the boiler circulation pump is running the system pressure rises and instead of going into the expansion vessel like it should do a bit of the water in the system gets exhausted through the pressure relief valve, resulting in less water in the system.
That then shows up on the gauge as low pressure when the pump is not running.

To be fair it is on the water system not the gas, so it’s not so much of a safety issue.
If the pressure drops too low then the boiler won’t let gas in and won’t fire up at all.

You can just keep topping up via the filling loop, many people in such a situation do, but the real solution is to replace the faulty expansion vessel and that’s a much bigger, more costly, job than just changing a gauge.

I still think that next time you visit I would be checking the service contract, (if there is a regular service contract), or if it was a one-off service just what was supposed to be covered for what your mum paid.

Other than that would be a choice of keep topping the water up as needed, or pay to have the expansion vessel replaced (or even get the boiler replaced).

Hi ​@TayUK 
As you are well aware diagnosing problems at a distance can be a real pain.

The standard Tado V3+ comes in three parts, the internet bridge (which is connected to the wi-fi hub), the controller (which is wired to the boiler) and the thermostat.

Is the Tado at fault?

A few things make me question that the Tado is faulty or not communicating as it should. The thermostat seems capable of transmitting back the current temperature, and the controller the state of the hot water, and also the control signal to the boiler (1, 2 or 3 bars relating to the colour of the shading). This suggests the three components are all talking to each other and also over the internet.
Also what changed on the 22nd after, several months, to cause the issue?

Looking at the various possibilities.

Low water pressure: If the pressure is marginal then increasing the temperature slightly, like heating the water cylinder, can increase the pressure in the system and cause it it start up. Your graphs from the 22nd and 28th both show the system springing back into life after a hot water cycle. By the way does the hot water cylinder heat up? If it is this again hints that it is not a Tado comms issue. Nukecad suggested that one possible cause is the over-pressure relief valve operating at too low a pressure. I think the EcoBlue has a separate expansion vessel and pressure relief (so cheaper to fix if this is a problem). It is a shame the gauge isn't working as this would make it much easier to check.

Faulty/sticking pump: It is possible that the circulating pump doesn't want to start. Our neighbour had this issue and would give it a deft tap with a spanner to persuade it to start (NOT recommended). This tends to show itself when the system has been off for a few hours. Once running it would run happily for the rest of the day until the next morning.

Faulty/Sticking zone valve: If the system is "Y" plan (it has a three port mid-position valve) then it may be that the valve is sticking. If the valve motor/actuator failed then generally you get hot water but no heating. If the return spring (within the valve) has failed then the valve can get stuck in the heating only state. I have seen washing draped over the valve (it does get nice and hot) which can cause the valve to jam.

Boiler bypass operating: Some systems have a bypass valve which ensures a minimum flow to the boiler. Basically when the flow through the radiators falls too low, the pressure from the pump rises and the relief valve operates diverting flow back to the boiler. This is common in systems with pump over-run where it is neccessary to maintain flow through the boiler when the valves close off. If this valve is sticking then it can be sending most of the water flow straight back to the boiler rather than through the radiators.

And there are always loose electrical connections on the Tado, boiler or valves.

In some respects fault finding with a Tado can be easier, as you can turn things on and off whilst watching the valves operate and feeling which pipes warm up.

Just food for thought really
 

Hi ​@TayUK, as ​@BeePee intimates, one of the Tadö parts, the sensor or the “room stat” bit, you may remember has three of the common small household batteries used in so many handsets etc. (AAA alkaline batteries) located in their own compartment.  To access them, the sensor is just gently disengaged (from the bottom edge, and then easing upwards) from its mounting bracket, no screwdrivers or other tools or indeed particularly strong or adept fingers required.  I’m wondering whether these batteries have maybe started failing a bit and whether that could account for months of good reliable boiler control fading into the sudden randomness in performance your Mother’s experiencing? I haven’t had my Tadö long enough to know whether there’s any self diagnosis that reports low battery reserve, or even whether that would account for the particular symptoms in this case?

Bit difficult, though, I appreciate, for you to check with new batteries from 150 miles away! Maybe a friendly neighbour would be prepared to be talked through things on the ‘phone?

Hope you get things sorted soon, all the best to you and your Mum for the New Year…

Hi ​@TayUK 

Whoops, never thought of the battery. Good spot!

You can check the battery status remotely using Settings > Rooms and Devices and then selecting the thermostat. You should see something like

Unfortunately it gives no idea of signal strength, just “connected”.

Ah, that’s interesting ​@BeePee, many thanks for that…I’d either forgotten or not explored properly in the first place! So far as the batteries are concerned, presumably a “good” implies there may well be a “fair” and/or a “poor” status at some future stage. Mine (installed around June ‘24, I think, so similar vintage to the one discussed by ​@TayUK) is still showing “good”, so I’ll check up on it periodically. Cheers again…

Our hive was showing “fairly good” after 12 months (not quite full green), however when you touched it to wake it up (to show the temperature) the radio comms became erratic for a while. So I changed the batteries. Took it a while to update the status over the app. So the app display may tell you if something is wrong, but not necessarily if all is well!

As an aside ​@TayUK I assume the radiator in the lounge does not have a thermostatic valve (or it is fully open)?

n.b. The screen shot was from (a different) neighbour that has their Tado fitted 12-Oct this year.

I think I mentioned previously that the water pressure is visible in the digital display which was reading 1.3 - 1.5 Bar, the analog one just reads nothing. My understanding is that for this boiler it was sitting in the optimum level when the system wasnt in use. 

Assuming that reading is to be believed, I think that rules out the pressure aspect of it. 

I was reading elsewhere that somebody mentioned their receiver and a few others that they had heard of had a relay problem, presumably this is where the link to the boiler is doesnt activate, despite the wifi side of things working.

This is starting to feel like that could be a contender too. At the moment I’ve only managed to rule out the wifi, and the other Tado devices (Temp sensor & Internet bridge), the receiver seems to work most of the time, but several times I cant recall it firing up the boiler when in test mode.   But thats anecdotal right now.   

No, she doesnt have any Tado TSV fitted, literally the only trigger for temps is down to the temp sensor (in the lough) as I mentioned, it has been working fine, the radiator is well away from the sensor.

The problem I currently have is that convection heaters I got my mum work really well, and if she doesnt call me and just puts the electric heater on then the temp rises and the sensor never triggers as its in the same room. 

today, its been a right pig and I’ve needed to force it to heat up 4-5 times, in almost all cases of simply forcing the temps up, it didnt work and required the intervention of turning hot water on to get it to spring to life.   I gave it until around 8am this morning and nothing then forced it through the app to increase/decrease temps then hot water off/on a couple of times, since I cant determine if the boiler is on for at least 10-15 mins its a painful process.  

Compare that to a day where it just worked on its own, it's a pretty different picture. 

We’ll get her plumber in after the holiday break and if he cant resolve it we’ll find somebody else to  get something in thats got a decent warranty/support contract in place. We cant be dealing with this all the time. 

Hi, 

I mentioned elsewhere here that some folks have seen issues with he relays not working 100% within the receiver, it appears to receive the “turn the boiler on signal”, this is shown by the LED coming on but nothing happens. beyond that.   There doesnt appear to be any feedback from the boiler or system to say that the command has worked only that the message has been sent by virtue of the slight delay and spinning timer completing on the app for couple of secs.   

At this time I dont think the boiler water pressure is an issue, my sister checked it again today and when not in use it was around 1.4 Bar, this would suggest that element is ok, I guess I cant rule it out. 

My own boiler a Worcester has the water pressure gauge and once during a service, somebody managed to cross thread the water filter assembly and it leaked a bit gradually draining to 0 bar  after a few days. 

I guess the key here to to get the experts involved, she has a work around albeit it prevent us trying to get it going again remotely.

I think at this point, we’ve reached what I can do remotely, we’ve agreed we will give her guy another shot, and then look at other options. 

thanks

BeePee wrote:

Hi ​@TayUK 

Whoops, never thought of the battery. Good spot!

You can check the battery status remotely using Settings > Rooms and Devices and then selecting the thermostat. You should see something like

 

Unfortunately it gives no idea of signal strength, just “connected”.

batteries good in her system, 

One of the first things I found in the app. all seems okay, the thing is when testing, anything that the temp sensor did resulted in some activity on the receiver side, so I think (?) the first 2 elements are fine, possibly something with the receiver ↔ boiler 

Putting the receiver into test mode (Using the small button top of the receiver) shows the power light flashing, and I think all the times I tested that the boiler kicked in a short while later.. but initially it might not have as I wasnt really looking for that initially. 

Hi ​@TayUK 

You are doing really well here!

I think the mid-position may be at fault.

The following diagram shows where the power should go when calling for heat

The valve opens fully and power is passed down the orange wire from the valve to the boiler and pump.

When you turn on the hot water the valve moves to the mid position. However there is now a direct feed from the hot water to the boiler.

So this SUGGESTS an issue with the 3-port valve, either loose wire or the microswitch within the valve isn’t operating correctly.

This requires either repairs to the electrics or a replacement valve actuator.

Let me know how you get on.

IF

(a big if) this is the problem then a temporary fix would be to set the boiler temperature slightly below the stat on the hot water cylinder. Why? That way the cylinder will never get up to temperature. Then set the hot water to come on at the same time as the heating. The water from the boiler will circulate around both water circuits (so less through the radiators) BUT the water will be hot. It will mean that the boiler will try to heat the cylinder all the time BUT since the water in the cylinder is hotter than the boiler setpoint it should never turn on (although the pump will continue to run).

Since you have boosted the hot water several times and each time the radiators have heated up this suggests you are not far from this situation anyway.

Hi ​@TayUK 

Did you manage to get this fixed? What was the diagnosis?

B

Not resolved yet, my mum is trying to get the Electrician and the plumber in together. It’s like trying to get any sense out of Trump, it's an almost impossible task. 

Given that (if it isnt heating when it should) if we persist in raising/lowering the temps or boosting etc it more often than not comes to life and then typically works for the day or at least some of it. the first point might be the issue. 

1. One is that the relay(s) in the receiver occasionally doesn't work, this is still my top target right now.   Forcing the water on just works (hitting the test button on the receiver), but not so the heating, it only seems to be related to the heating side. That could be the sticky relay that has been mentioned.

2. I’ve seen some other anomalous things happening, the Receiver has been unreachable a few times now remotely late at night, which meant I couldnt really do anything, I cant advanced anything or raise lower the temps, its always happened late at night. nothing I do brings that element back to life.  It's always sprung back to life at one point before the schedule kicks in.  Not sure if this has any bearing. 

Thats kind of where we are right now, I’ve visiting again back end of January so I can look at it again if it's not been resolved.  My sister is in the process of changing her broadband to fibre with an emphasise on ensuring wifi coverage is significantly better. 

thanks for asking though. 

Hi ​@TayUK 

My understanding is that the Tado comes in three parts.

• Wireless Temperature Sensor
• Wireless Receiver (Programmer with Hot Water Control)
• Internet Bridge

The internet bridge I believe is wired directly into the wi-fi router, so this connection is wired and not wireless. The wireless connection between the three units is totally independent of the wi-fi router and uses a totally different frequency (868 MHz  aka 6LoWPAN) . So changing broadband and wi-fi router should not have any effect on the operation of the Tado.

I think you mentioned that (currently) the schedules are stored in the cloud so if internet is lost then the schedule sticks with the current settings until the internet is restored.

I have a Hive system and it frequently tells me that it cant connect to stat or boiler and then after a few seconds tells me all is well. I have checked signal strength and it says it is fine. A neighbour has the Tado (they lost water pressure and the symptoms were initially similar to yours). The Tado seems much more reliable although the internet bridge is situated half way between the boiler and the stat.

As you suggest could be dicky relay, loose wire, or issues with the diverter valve.

I sympathise with your predicament. My mum lives 75 minutes drive away. In one respect she is fortunate to be living in a council house so slightly easier to get people in to fix it (although often takes three visits before it is fixed). Every time I go over I check pressures and temps just to make sure.

We’re trying to rule out anything that could have some influence over the system.  There are other reasons for changing the broadband too,  but as I do not know fully how the Tado connectivity works we thought we’d hedge our bets, there are issues with connectivity in the house and frankly its 2024 she needs to keep up with the tech, plus family coming round it helps too.  

I contacted Tado over Christmas and they enabled offline scheduling so that shouldn’t be an issue now. This doesnt appear to have any bearing on the issues were seeing. 

The offline issue seems to be something new, what I see is show below, it may or may not have any bearing on this issue but I cant rule anything out. the other device report as being online, since Im concentrating on the receiver this sent up the flags..I noticed last night too but when I check at 7am it was contactable again.  

Sorry ​@TayUK I was being a little slow. This relates to the broadband not the heating.

Again the IF.

Is your mother being converted to fibre only, where the phone line is replaced by VOIP (Voice over internet)?

With conventional “copper” systems the wires to the exchange share the internet signal and the voice signal for the phones (hence the splitter they often provide). The exchange also supplies the power to the phones (the REN or ringer effective number on each phone determines how many phones the exchange can drive). Your voice travels as an analogue signal to the exchange where it is converted and passed over their network.

On fibre/VOIP systems a small (home powered) interface converts the incoming signal to something suitable for the WAN socket on the back of the router. The router then communicates with VOIP handsets over wi-fi. Your voice is converted to a digital signal which is passed over the internet. Less demand on the exchange as it is dealing only with digital signals and clearer communications and less noise.

The problem: The interface and router are powered my the home’s electricity supply, so, in the event of a power cut, the “landline” phones will not work. If the occupant is vulnerable then they may fit battery backup to the two units but these are rather bulky (each bigger than the router). Also many care alarms are not compatible, however the BT Hub does have a “conventional” phone socket on the back that the alarm can plug into. Finally the changeover is not seamless (well the two I know of weren’t). There can be a period of several weeks when (I think this was the way round) incoming calls come in on the old phone line, whilst outgoing calls must be made on the new system.

So worth checking what is being fitted?

And finally some providers provide “essentials” packages (see BT Home Essentials Broadband | Universal Credit Broadband sorry for the BT plug but this is what my mother is on). 36 Mb/s should be ample for your mother on her own as this would easily cover streaming UHD movies.

Sorry to give you something else to think about.

B

She has had various copper based BB for a number of years, only recently since moving lots of stuff to sky has she had problems with it.  

Over the last coupla months she has been complaining about poor wifi speeds, I know, I know, wifi nothing to do with BB per se, but this links into another issue.  

She has pretty poor cellular coverage for all the major providers, her house is solid!! despite being a bungalow when we had this built 15-20 years ago, we wanted it built to exceed current standards at the time.  Its got great insulation and terrible cellular signal.   

I did once consider a pico cell to boost cellular but it was too much like hard work, Im a retired Global Network Manager (You did such a nice explanation of how it all works too, sorry), and even I baulked at the cost of the fixed line behind the pico cell.    

So we utilised wifi calling, this meant she generally had better cell calls when in the house. Then several months back people were complaining about calls dropping on the mobile. Eventually I decided it was probably all to do with the BB, even her home POTS phone dropped calls sometimes. Clearly there is an issue there and it needs to be sorted, there is no equipment needing that old circuit and frankly its the weakest link, she still has a mobile that works should he landline die. If needs be and at some time in the future I can stick a UPS in there but as I said, she has a mobile. 

It’ll be fibre going in, City Fibre stuck in some fibre earlier in the year and this is live in the area, I saw a few nice deals with decent wifi extenders but my sister wants to give Sky a kicking and get them to sort it, maybe they’ll offer her fibre, I’m not sure if Sky would simple use open reaches fibre or if there are deals to utilise City Fibre.     

I’m now impatient and just want it done, monitoring her security cameras over fibre would be significantly better for me too, and I might just put some remote management for her Apple devices too, supporting an 85 ish year old with tech is, erm, challenging at best.. 

Current latency and jitter are dire. A digital phone really cant be much worse to be honest, she also has a ton of static on her deck handsets occasionally, this could be line noise or the phones, we’re just trying not to change to much lest we introduce further issues.

Making sure she dials the full telephone code could one interesting though.

Interesting Tado system sprung to life this morning after all devices were showing offline (I think this was just her broadband playing silly buggers as her security cameras were showing as offline too. 

There appears to be a multitude of issues, being remote means fixing them all one at a time is a challenge.