Best Wifi enabled thermostat

[Sheepshanks]

KTF said:

When it eventually gets to 17.5c the house is warm

Really? I know people are different but I wouldn't have said 17.5 is warm - if you're just sitting around in the house.

If the rads are hot then as said above, they're not big enough or you're losing too much heat. It does seem to have been colder over the last week or so than the outside temps suggests - here in the NW it's milder today, but I gather the SE is still very cold.

[KTF]

Sheepshanks said:

What happens if you set the room stat to a more normal temp, like 20C?

I'm assuming you're not using a bus connected version of the Tado?

We have ours"controlling" both CH & HW on a 2 port valve system - so, of course, all Tado is doing is opening the valves.

Boiler ramps up fast to it's set flow of 67C and generally just sits there. Rads get hot pretty quick. As the smart TRVs shut down various rads the flow temp will creep up to maybe 72C and then the burner shuts off for a few mins, wiht the temp dropping to maybe 50C (I don't think that's a settting, I think it just drops to that in the time it's on overrun) and then repeats.

The only slightly odd thing is that sometimes when the boiler (Glow Worm Energy 7) refires it stays at a low burner rate and doesn't ramp up fast so takes a long time to get back to 67C. Clearly that's something the boiler itself is deciding but I don't know if it's a glitch or if something in its software is telling it to say at a low burner rate - maybe it's connected to flow rate through the boiler, but I'm completely guessing there.

Have not set it any higher but I would assume it would just call for heat (3 wiggles) and continue as it does. Given the way its operating I doubt it would ever get to 20 anyway.

I am not using the bus version, I just swapped out a wired room stat (3 wires) for the wired Tado room stat. Controller next to the boiler is set to 24h as the Tado is then controlling the on/off using its programs.

The boiler has a display showing the flow temp and flame power. It ramps up to 70 on 6 'flames' and the the flame goes down to 1 once it reaches 70 to keep it ticking over at that temp and is what it does when hot water is on but heating off.

[Sheepshanks]

Trustmeimadoctor said:

it should start at a low temp and build up rather than firing at max temp to stop it overheating

It normally does that, but sometimes doesn't ramp up.

Thinking about it, I caught it out 'manually' once when I opened the hot water motorised valve while the boiler was between burn cycles and the flow temp dropped rapidly - when it restarted it just stayed low and was gaining heat at a very slow rate. I shut it all off, restarted and it was fine. So I think it's a glitch.

[KTF]

Trustmeimadoctor said:

it doesnt need to go higher!
it does seem that tado is playing silly buggers

usually, rads are too small in halls this was so they didnt switch off before the rest of the house got to temp.
one of the issues are we dont know how hot the ch water actually is the rad will feel hot as long as the rad is warmer than your skin temp

one of the issues you have is if you swap out the rad in the hall you will potentially get it stopping the heating in the rest of the house before its got up to temp if those rads are also undersized

id try turning off alll the compensations on the tado and see how you get on so like the smart start and stop functionality and see if it changes how it heats

do you have all the trv's set to sensible temps around the house or have you turned a bunch of them off as its possible it actually the boiler getting too hot and then shutting down to stop it overheating or potentially other reasons

what graphs do you have you can share

The TRVs are Drayton TR212. None on the hall rad as that is where the room stat is but in the bedrooms they are set to 4, the living room to 3 (there are 2 rads in there so is the warmest room), dining room is set to 2 as it isnt used and the bathrooms have none.

When the TRV get to the temps you can hear them whistle as the valve closes so they are working. I would then expect the remaining heat to be channelled to the hall radiator and bathrooms as they dont have TRV fitted.

Here are the graphs from the weekend. Dark grey is 3 wiggles on the Tado app which is when it actually triggers the boiler and pump.

Edited by KTF on Monday 23 January 11:57

[Trustmeimadoctor]

that is what it should do

but it does seem then like the rad just isnt giving out enough energy to make a real dent in the loss of the room

but as you say it used to work so therefore the system should be capable of heating the house in a decent time frame

Or was it always off you just didnt notice it

id turn off the smart bits of tado like i say and get it working more like what you had and see if it changes for the better or just pull it out and put the old one back in and see if it fixes it

[KTF]

Sheepshanks said:

Really? I know people are different but I wouldn't have said 17.5 is warm - if you're just sitting around in the house.

If the rads are hot then as said above, they're not big enough or you're losing too much heat. It does seem to have been colder over the last week or so than the outside temps suggests - here in the NW it's milder today, but I gather the SE is still very cold.

The stat is in the hall and 17.5 that normally translates to 18-20 in the living room (checked with a thermometer) as the two radiators there are turned off by the TRVs and we keep the door closed.

.

[Sheepshanks]

KTF said:

The boiler has a display showing the flow temp and flame power. It ramps up to 70 on 6 'flames' and the the flame goes down to 1 once it reaches 70 to keep it ticking over at that temp and is what it does when hot water is on but heating off.

If the flow temp is actually 70C (and the display isn't just showing what it's set for?) then the rads should be hot (are they hot pretty wel all over?) and the problems with the house not getting can only be with the rads not being big enough and / or the house losing too much heat.

The reading off the Tado TRVs are close to nonsense, but our kitchen diner is controlled by a Tado wall 'stat, so I assume that's a bit more accurate. It's going down to 15C overnight (boiler is off, Tado on frost setting) and in an hour in the morning it's at 19C.

Edited by Sheepshanks on Monday 23 January 12:07

[KTF]

Trustmeimadoctor said:

that is what it should do

but it does seem then like the rad just isnt giving out enough energy to make a real dent in the loss of the room

but as you say it used to work so therefore the system should be capable of heating the house in a decent time frame

Or was it always off you just didnt notice it

id turn off the smart bits of tado like i say and get it working more like what you had and see if it changes for the better or just pull it out and put the old one back in and see if it fixes it

I dont recall the house taking such a long time to warm up. Looking at the gas usage, we are using more gas this January with a smart stat than we did with a conventional one and the weather was similar from what I recall.

I have had a look on the app and can find no way of disabling all the smart features.

I am tempted to swap it back to the old dial thermostat to see how it behaves. If it is better then buy a Honeywell T3 which I can program and get rid of the Tado all together. It should work though.

Another thought is to adjust the lockshield on the hall radiator. It looks like its pretty much closed off so maybe a bit more flow would help it heat up better.

[KTF]

I checked the hall radiator lockshields. The flow is from left to right.

The lockshield on the left was wound down to closed then opened a quarter turn. The one on the right was fully open then wound back a quarter turn. This meant that there was a restricted flow of water getting to the hall radiator. I can see why you would want this so water was pumped round the other rads but maybe it was a bit too restricted?

I have swapped them over so the left one is a quarter turn down from the top and the right one is a quarter turn from the bottom. This means the radiator will now get a much better flow of warm water which should then help the room stat temperature.

Will monitor it and see if that made any difference.

[KTF]

Sheepshanks said:

If the flow temp is actually 70C (and the display isn't just showing what it's set for?) then the rads should be hot (are they hot pretty wel all over?) and the problems with the house not getting can only be with the rads not being big enough and / or the house losing too much heat.

The reading off the Tado TRVs are close to nonsense, but our kitchen diner is controlled by a Tado wall 'stat, so I assume that's a bit more accurate. It's going down to 15C overnight (boiler is off, Tado on frost setting) and in an hour in the morning it's at 19C.

Edited by Sheepshanks on Monday 23 January 12:07

On the boiler there is an up down to set the flow temp. Once set, you see the real time water temperature which goes up and down depending on flame amount. All radiators are getting hot (they were not before which is why I had the system power flushed).

All TRVs are conventional. I tried a Tado one but it was so inaccurate I took it off again.

[Trustmeimadoctor]

KTF said:

I dont recall the house taking such a long time to warm up. Looking at the gas usage, we are using more gas this January with a smart stat than we did with a conventional one and the weather was similar from what I recall.

I have had a look on the app and can find no way of disabling all the smart features.

I am tempted to swap it back to the old dial thermostat to see how it behaves. If it is better then buy a Honeywell T3 which I can program and get rid of the Tado all together. It should work though.

Another thought is to adjust the lockshield on the hall radiator. It looks like its pretty much closed off so maybe a bit more flow would help it heat up better.

you really need to see what temp the rad is getting to and how much heat its loosing across the rad

some trv's a 1/4 turn can be almost fully open others not even open !


but this is a perfect example of swapping out to smart control and them not saving anything.



just thinking so your saying the other rooms are getting up to temp fine its just the hall?

[KTF]

Trustmeimadoctor said:

you really need to see what temp the rad is getting to and how much heat its loosing across the rad

some trv's a 1/4 turn can be almost fully open others not even open !

but this is a perfect example of swapping out to smart control and them not saving anything.

just thinking so your saying the other rooms are getting up to temp fine its just the hall?

Yes, I realise it should be what, circa 10c drop between the in and out on the rad? I do have a thermometer gun somewhere but cannot find it at the moment so a bit of manual twiddling cannot do any harm at the moment.

All other rooms are getting up to temp fine, its just the hall that seems to take forever and as this is where the stat is located its impacting the whole system.

Already after adjusting the lockshields the hallway seems a lot warmer and now I would not want to touch the radiator for very long so there is more heat coming out of it. Will see how that translates on the Tado graph.

I think the problem with the Tado is that if you have a dumb boiler connected to it then you are not actually gaining much. There are three 'wiggles' on the Tado display where is is meant to be modulating the flow up and down on the boiler but only when I have three showing does it actually call for heat.

[8.4L 154]

Not sure Tado doesn't give much on a dumb boiler, it can do some very good boiler management modulating the boiler fire duration based on demand and forecast temperatures, its not going to be as good as an opentherm thermostat controlling the water temp but it can do a lot more than dumb random on/off with hysteresis etc.

As for the rad in the hall, is it possible the person who balanced the system deliberately left that one throttled down a touch as Trustmeimadoctor said the last thing you want is the hall with the thermostat heating up first and turning the whole house off. If its under size or under supplied then everywhere else gets heat supplied until their TRV's shut down at which point the hall rad gets all the heat it wants when its the only remaining room calling for heat. Maybe they just throttled it back a touch too much so it cant achieve the set point or if you open it up then you will have a toasty hall and freezing lounge.

Edited by 8.4L 154 on Monday 23 January 14:28

[KTF]

8.4L 154 said:

Not sure Tado doesn't give much on a dumb boiler, it can do some very good boiler management modulating the boiler fire duration based on demand and forecast temperatures, its not going to be as good as the thermostat controlling the water temp but it can do a lot more than dumb random on/off with hysteresis etc.

As for the rad in the hall, is it possible the person who balanced the system deliberately left that one throttled down a touch as Trustmeimadoctor said the last thing you want is the hall with the thermostat heating up first and turning the whole house off. If its under size or under supplied then everywhere else gets heat supplied until their TRV's shut down at which point the hall rad gets all the heat it wants when its the only remaining room calling for heat. Maybe they just throttled it back a touch too much or if you open it up then you will have a toasty hall and freezing lounge.

I realise it can be more useful with its logic, but sometimes I do wonder if its being too clever for its own good. Its very difficult to compare like with like though as there are too many variables even if you swapped over on a daily basis.

I can see why they would have wound it down for the reasons you said but maybe they were a bit to aggressive with it. With all the TRVs having shut down the radiators in the rooms, the bathroom rads were still very hot as they were acting as the bypass with only a trickle of heat coming out of the hall.

Meanwhile the stat was still calling for heat and not really getting anywhere. I honestly think that if the heating was set to 21 it would not actually have reached it from a start of 16c before it was bedtime again the way it was behaving.

Its lockshield settings easy enough to change back so will see what happens this evening and tomorrow morning.

[Trustmeimadoctor]

all i can say is
its not easy being green....

i have leaned a lot this year from playing around with this stuff.
and when you get a win its good

but yeah as i said earlier your radiator was too small not physically but as it was restricting the flow below what is required to provide x watts of energy you need
say your needing 800w of energy at 0 to maintain your temp then 801 wil make it increase very very slowly 900 will heat it up even faster but your rad can only physically give out a certain amount of energy at a given flow


what size and type of rad is it? 2-panel fins on both sides?

[8.4L 154]

KTF said:

I realise it can be more useful with its logic, but sometimes I do wonder if its being too clever for its own good. Its very difficult to compare like with like though as there are too many variables even if you swapped over on a daily basis.

I can see why they would have wound it down for the reasons you said but maybe they were a bit to aggressive with it. With all the TRVs having shut down the radiators in the rooms, the bathroom rads were still very hot as they were acting as the bypass with only a trickle of heat coming out of the hall.

Meanwhile the stat was still calling for heat and not really getting anywhere. I honestly think that if the heating was set to 21 it would not actually have reached it from a start of 16c before it was bedtime again the way it was behaving.

Its lockshield settings easy enough to change back so will see what happens this evening and tomorrow morning.

I'm not a heating engineer butI think that's your problem, when the rest of the house has shut off then the bathroom is the least resistance and the hall still isn't getting anything. I'd be tempted to put a bit of restriction in the bathroom rads to see if it forces some into the hall when its just the last few uncontrolled rads running. You just need to find the balance between messing up the rest of the house or not getting the bathroom hot. Are the bathroom rads lockshields wide open?

[Trustmeimadoctor]

This is why you want auto balancing trv's

Once set it doesn't matter if they are all closed or not the correct flow still goes to the rads that are open they don't speed up or have issues

[8.4L 154]

Trustmeimadoctor said:

This is why you want auto balancing trv's

Once set it doesn't matter if they are all closed or not the correct flow still goes to the rads that are open they don't speed up or have issues

And that's my plan for warmer months. End of the day without them your chasing your tail. Even if you got the system perfectly balanced on any particular day with TRV's different room heat losses or solar gains you have no chance of maintaining that balance as the whole thing is dynamic and ever shifting and each TRV movement is having a knock on effect into the rest of the system all the time. Auto balanced TRV's and all that goes away, the TRV just reacts and supplies the right flow for whatever pressure the system is currently at.

[KTF]

Trustmeimadoctor said:

all i can say is
its not easy being green....

i have leaned a lot this year from playing around with this stuff.
and when you get a win its good

but yeah as i said earlier your radiator was too small not physically but as it was restricting the flow below what is required to provide x watts of energy you need
say your needing 800w of energy at 0 to maintain your temp then 801 wil make it increase very very slowly 900 will heat it up even faster but your rad can only physically give out a certain amount of energy at a given flow


what size and type of rad is it? 2-panel fins on both sides?

640 x 700. Single panel with fins at the back. Mid-80s as it’s original to the house.

[paralla]

We have a couple of rads that don't have Tado TRV's (no TRV's at all) on them and I'm forever explaining to my other half that whenever any of the zones is calling for heat the radiators without TRV's will come on, one of those is a big radiator in the hall/stairway of a very open plan five level layout.

The stat for the heating is on a wall at the top of the stairs but in a room with a double height ceiling. Trying to get the heating to heat the room stat to a certain temperature is pointless because it means the (double height) front room would have to be maybe 4 - 5 degrees hotter than the main heating thermostat. I set the set point of the room I'm in to what I want it to be and don't really care what the temp is at the top of stairs on the main thermostat. In my case separate zones for the rooms/levels that I'm using is really useful and might be beneficial to KTF.

If the temperature rise/fall rate at the fixed thermostat location isn't similar to that of the rest of the house it's always going to be a compromise and lead to inefficiency.

Go all in and zone your system.