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I’m writing this on behalf of my 85+ year old mother. Apologies for the long post but it does explain pretty much perfectly the issue. 

 

Shes with OVO and has been for many years, this year her very old manual thermostat started playing up and heating was coming on in the middle of summer and was a nightmare. 

 

I saw the Tado V3+ (Wireless Thermostat, Internet bridge and wireless receiver) deal OVO were offering earlier in the year and she bought it.   Eventually an electrician installed this around June, it's been working perfectly since then with her Baxi EcoBlue boiler.

 

As she is on approaching 90 and is quite frail, shes like to have the heat on so its been working from around October/November time, she likes it at an indicated 23degs. I dont think it is quite that high but feels better than the 14degs  on her old thermostat!! 

 

We have a schedule setup so from 10pm-7am daily she has it set at 14 degs C, 7am-10pm 23degsC. 

Her bungalow has exceptional insulation and over night, even when its cold outside it rarely drops below 18-19 degs C, During Oct/Nov the heating would come on at 7am and keep the temps pretty consistent at 23 degs C.  Until a few weeks ago. 

 

Often it comes on at 7am then just stops, you can see on the chart displayed on the app where it starts then heat just starts dropping, it drops slowly due to the insulation. 

 

I carried out some tests whilst up there as I feared it might be the wireless causing issues, using the app triggers the receiver but sometimes its just doesnt. The tests on the receiver only for the most part worked well, the boiler typically came on after 30s-1min.. But the test buttons only turn on the system for a few mins then turns off by design I presume.

 

By upping the temp on the app and sometimes hitting the hot water button on/off the system springs to life, others it doesnt. She could have heating all day, other times it doesnt work and requires lots of intervention to get it working.  Its starting to get very very annoying and frankly its close to getting ripped out, we cant have my mum using this system as its too unreliable and at this time of year its not good at all.

The following chart shows it working well on the 21/12 and rubbish with lots of cut outs on the 22nd,  when it comes on it would have been manual intervention (Perhaps lots of it) .     

 

 

 

Frankly were at our wits end with this system (I live 150miles away so its not easy to just pop in), is it worth persevering, is support offered through OVO or Tado?, I’m tempted to send it all back to OVO and putting something old school back in that works ? 

 

As a backup I’ve bought her some convection heaters, but the down side to that is the heating is unlikely to kick in as the thermostat is in the lounge and with that heater is nice and toasty, but now trying to get to the bottom of the issues is even harder.  Its also getting expensive.

 

This isnt great for a vulnerable person at this time of year. 

 

Help please

Is the Baxi EcoBlue boiler a standard boiler (there is a hot water tank) or is it a combi system? Also is it a sealed system (expansion tank) or a vented system (a tank in the loft). Is it making a gurgling noise when the pump runs?

Why the questions?

I suspect this isn’t a problem with the Tado. The symptoms are similar to a sealed system losing water pressure. The Baxi should show an error code if the pressure is low (E 118) and the pressure gauge should normally show between 1 and 2 bar anything less than 0.5 bar indicates an issue.. IF this is the problem it is relatively easy to fix. Does your mother have a neighbour that can pop in and check? They should also check if any of the radiators are leaking.


Hi ​@TayUK 

Did you manage to diagnose the problem?


Is the Baxi EcoBlue boiler a standard boiler (there is a hot water tank) or is it a combi system? Also is it a sealed system (expansion tank) or a vented system (a tank in the loft). Is it making a gurgling noise when the pump runs?

Why the questions?

I suspect this isn’t a problem with the Tado. The symptoms are similar to a sealed system losing water pressure. The Baxi should show an error code if the pressure is low (E 118) and the pressure gauge should normally show between 1 and 2 bar anything less than 0.5 bar indicates an issue.. IF this is the problem it is relatively easy to fix. Does your mother have a neighbour that can pop in and check? They should also check if any of the radiators are leaking.

 

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.

 

 


Hi ​@TayUK 

Did you manage to diagnose the problem?

 

 

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.


The gauge on the front of the boiler does not work, it was serviced several weeks ago,

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 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).

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.   


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.

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 ​@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, 

 

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

 


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.


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