Home heating automation

deezell

For solar you want the boiler to only heat the top third, and the solar preheats the lower section. Hot water rises to the top, so higher up stats will read higher.

john_doe.

deezell wrote: »

For solar you want the boiler to only heat the top third, and the solar preheats the lower section. Hot water rises to the top, so higher up stats will read higher.

Thanks , what is best location for Sonoff in that case during winter months when solar is not contributing.

Or in general where do people typically locate temperature probes on the tank ?

deezell

I presume the Sonoff is controlling the firing of the boiler for HW? It would be fine where it is. It will call the boiler for longer if the incoming water is colder due to it being winter, and also less solar pre heating. Once heated, the hot water tends to stay in a layer on the top of the cylinder, usually enough for most needs, and incoming cold will trigger the stat to fire the boiler while you still have a reserve of hot above the stat location. The further down the stat the bigger the reserve. I don't see the point of timed HW any more with modern highly insulated cylinders, unless you have solar (or also solid fuel boiler stove) and you want to maximise it's efficiency by having it on as long as possible before you allow the boiler to respond to the topmost stat. On dull or cold days you might end up with cool or cold HW if you're too frugal with timed HW events.

john_doe.

deezell wrote: »

I presume the Sonoff is controlling the firing of the boiler for HW? It would be fine where it is. It will call the boiler for longer if the incoming water is colder due to it being winter, and also less solar pre heating. Once heated, the hot water tends to stay in a layer on the top of the cylinder, usually enough for most needs, and incoming cold will trigger the stat to fire the boiler while you still have a reserve of hot above the stat location. The further down the stat the bigger the reserve. I don't see the point of timed HW any more with modern highly insulated cylinders, unless you have solar (or also solid fuel boiler stove) and you want to maximise it's efficiency by having it on as long as possible before you allow the boiler to respond to the topmost stat. On dull or cold days you might end up with cool or cold HW if you're too frugal with timed HW events.

Thanks , at moment no, it's just measuring the hot water temperature. The hot water control is located in another room. I was thinking of adding a Sonoff there also to fire the boiler based on the other one falling below temperature.

Dr4gul4

john_doe. wrote: »

Thanks , at moment no, it's just measuring the hot water temperature. The hot water control is located in another room. I was thinking of adding a Sonoff there also to fire the boiler based on the other one falling below temperature.

I've the same set up, solar reads both probes, DS sensors, so i installed two th16's and attached them to the outside of the tank ( there's a diff of about 3 - 5 degrees due to this )

I have in turn wired a shelly 1 as my "hot water timer" and a sonoff pow at the motorized value . when the temp at the top of the tank drops below 40 degrees the automation fires up the shelly ( timer) which activated the heating control board, fires the boiler and main pump, and the automation in turn opens the motorized valve.

All is shut off once the Temp hits 55 / 56 degrees at the top sensor.

Took a while to get all wired up due to the horrible heating controls. but working well now.

john_doe.

Dr4gul4 wrote: »

I've the same set up, solar reads both probes, DS sensors, so i installed two th16's and attached them to the outside of the tank ( there's a diff of about 3 - 5 degrees due to this )

I have in turn wired a shelly 1 as my "hot water timer" and a sonoff pow at the motorized value . when the temp at the top of the tank drops below 40 degrees the automation fires up the shelly ( timer) which activated the heating control board, fires the boiler and main pump, and the automation in turn opens the motorized valve.

All is shut off once the Temp hits 55 / 56 degrees at the top sensor.

Took a while to get all wired up due to the horrible heating controls. but working well now.

Thanks what's the Shelly doing via the timer?
First Sonoff measures the temp and then the Shelly is used as a "relay", where do you control the timer routine of the Shelly?

Also what does the Sonoff POW do ?

Dr4gul4

john_doe. wrote: »

Thanks what's the Shelly doing via the timer?
First Sonoff measures the temp and then the Shelly is used as a "relay", where do you control the timer routine of the Shelly?

Also what does the Sonoff POW do ?

Apologies, should have been a touch clearer perhaps ...

I run Home assistant on a Pi3+, it runs an automation based on the Temp associated with the TH16 at the top of the tank. and that automation in turn must active the shelly and the POW.

The shelly is wired in to the Legacy control panel for the heating ( legacy controls were simple on/off based on time, driven by a separate time controller unit.

The Pow is used to control the motorized Valve to open the loop to allow the boiler drive hot water to the tank.

So the automation must enable both devices when hot water is required, and in turn disable once the temp reaches a set level.

john_doe.

Dr4gul4 wrote: »

Apologies, should have been a touch clearer perhaps ...

I run Home assistant on a Pi3+, it runs an automation based on the Temp associated with the TH16 at the top of the tank. and that automation in turn must active the shelly and the POW.

The shelly is wired in to the Legacy control panel for the heating ( legacy controls were simple on/off based on time, driven by a separate time controller unit.

The Pow is used to control the motorized Valve to open the loop to allow the boiler drive hot water to the tank.

So the automation must enable both devices when hot water is required, and in turn disable once the temp reaches a set level.

Ah okay yes. I was looking at the Sonoff mini as an alternative to the Shelly. Can you set boosts and overrides via HA?

I was looking to do something similar with hot water control and automate it via temp control with boost or override, away function etc..

Similar on heating side , I was looking at placing temp sensors in rooms like xiaomi , challenge is that in HA for time scheduling for heating the interface options aren't super. There is the "schedy" option I was looking into.

Dr4gul4

john_doe. wrote: »

Ah okay yes. I was looking at the Sonoff mini as an alternative to the Shelly.

Either Or would suffice, altho I have a little more faith in the shelly products given how connected the devs are to the community. Personal pref I guess.

john_doe. wrote: »

Can you set boosts and overrides via HA?

In theory yes, boost is just a 1 hour timer, or a 1 + hour increment depending on how many times you push the button, it's all code at that level in HA.

john_doe. wrote: »

Similar on heating side , I was looking at placing temp sensors in rooms like xiaomi , challenge is that in HA for time scheduling for heating the interface options aren't super. There is the "schedy" option I was looking into.

When it comes to heating it becomes slightly more complex, one thermostate, one zone, etc. I have UFH here, and thermo's in each room for each zone. There not perfect, but to replace them would involve a lot of replacing, not something I need to do right now.

I have though about replacing the timer that controls my UFH however, to manage the step back facility ( not something we've used yet ) a 4chan pro would suffice here maybe and it would also replace my Shelly timer switch as it's technically the 3rd zone on the heating.

mloc123

I currently have a Tado stat, which is hardwired (replaced an old wall stat).

I also have an extension kit, still box which I would like to use to control my immersion... is this possible? I assume I could wire it to replace my existing immersion switch but can the Tado app handle this? It seems you either use a hardwired stat OR an extension kit.

deezell

mloc123 wrote: »

I currently have a Tado stat, which is hardwired (replaced an old wall stat).

I also have an extension kit, still box which I would like to use to control my immersion... is this possible? I assume I could wire it to replace my existing immersion switch but can the Tado app handle this? It seems you either use a hardwired stat OR an extension kit.

You can add an extension kit and pair it to a tado stat, but you can still call the boiler via the currently connected stat terminals. The HW terminals on the ext kit do not have sufficient current rating to power an immersion element, so you would need a mains contactor or relay of at least 16A rating to supply the immersion element, triggered by the HW mains output of the ext kit.

s7ryf3925pivug

I got bosch smart trvs on rads, bosch smart heating control, bosch combi gas boiler, new gas pipes and external tank, domestic pump, mixer shower for a about 7k.

Standard Toaster

I currently have a EPH 4ch programmer, paired to the conventional oil
boiler, multifuel stove and solar for water system. (3 coil tank)
https://www.ephcontrols.com/section/4-zone-programmer-2/

Zones are water, living, bedroom, upstairs area.

I was wondering if the Drayton Thermostat 3 would be a straight swap for
this?

deezell

Standard Toaster wrote: »

I currently have a EPH 4ch programmer, paired to the conventional oil
boiler, multifuel stove and solar for water system. (3 coil tank)
https://www.ephcontrols.com/section/4-zone-programmer-2/

Zones are water, living, bedroom, upstairs area.

I was wondering if the Drayton Thermostat 3 would be a straight swap for
this?

Base plates for the wiser controllers are standard 6 terminal, with different pin designation for the 3 channel, (2 CH and 1 HW) to the 1 and 2 channel.
EPH 4 channel uses an 8 terminal baseplate.
With the kit 3, you'll need a second Kit 1 for the extra CH zone, with its own receiver/controller. The base plates for these are easily wired in place of the 8 terminal EPH plate.

Standard Toaster

Ah arse. I want to avoid that. I'll return them I think. Would the Evohome be a good alternative?

Any other options?

deezell

Standard Toaster wrote: »

Ah arse. I want to avoid that. I'll return them I think. Would the Evohome be a good alternative?

Any other options?

You'll be re-wiring no matter what. Do you have wired wall stats on each CH zone? Tado will wire directly in to replace these. Three stats and an ext kit will control the 4 zones, but you could leave HW timing to the EPH, leave it in place.
If you have no stats and only have timed control via the EPH, then the Wiser Kit three will give you 2 wireless stats for 2 of your CH zones. You could combine the top two zones into one, and later introduce some Wiser TRVs to give additional control within this zone, dropping out certain rads when heating not needed. A single receiver will cover this

Standard Toaster

No stats, just the EPH unit. I might just do that so, 3 channel kit arriving tomorrow. The upstairs zone is just attic space right now. I'll wire that zone to the bedroom zone and turn off the rads in the attic for now.

Drayton support said their unit should fit the EPH backplate (eph manual says it's British standard) so I bought it based off that. I partly at fault too as I though it was 3ch + water. Thanks deezall, I'm back on track.

deezell

Standard Toaster wrote: »

No stats, just the EPH unit. I might just do that so, 3 channel kit arriving tomorrow. The upstairs zone is just attic space right now. I'll wire that zone to the bedroom zone and turn off the rads in the attic for now.

Drayton support said their unit should fit the EPH backplate (eph manual says it's British standard) so I bought it based off that. I partly at fault too as I though it was 3ch + water. Thanks deezall, I'm back on track.

Eph backplate has 8 terminals, but a 6 terminal unit like the kit3 should click on to it. Mechanically it might engage, but electrically they are different.
From the left, the kit 3 is Neutral, Live, CH1, HW, CH2, Unused.
N, L, C1, HW, C2, U.
The EPH is Live, Neutral, Zone1, Unused, Zone2, Zone3, Unused, Zone 4
L, N, Z1, U, Z2, Z3, U, Z4
You will have to rewire entire EPH base, so just bin it and fit Wiser base.

deezell

You might get €40 on Donadeal for the EPH, so you'd need it's base to flog it.

Standard Toaster

Very helpful as usual, thanks for the info. Will let you know how I get on.

AstraMonti

Hey just an FYI. I had an issue with my Tado that certain rooms wouldn't kick off the heating. After getting on to support, they told me my system was setup that only two rooms had the ability to kick off the boiler but they changed it on the spot so most zones could individually power on the boiler if the room needs heating. There is a limit of 10 rooms btw, so if you have more you will need to select which ones would have that ability and the rest will only heat up if the boiler is already on.

This is of course undocumented and not a user choice, I left feedback that it should definitely be included in the app.

limnam

AstraMonti wrote: »

Hey just an FYI. I had an issue with my Tado that certain rooms wouldn't kick off the heating. After getting on to support, they told me my system was setup that only two rooms had the ability to kick off the boiler but they changed it on the spot so most zones could individually power on the boiler if the room needs heating. There is a limit of 10 rooms btw, so if you have more you will need to select which ones would have that ability and the rest will only heat up if the boiler is already on.

This is of course undocumented and not a user choice, I left feedback that it should definitely be included in the app.

Is that limit due to if you pay for the sub or?

AstraMonti

limnam wrote: »

Is that limit due to if you pay for the sub or?

Nothing to do with pay, it appeared to me that it is a hard limit on the software, for whatever reason.

keane2097

Hi folks, my immersion is currently controlled by one of the standard Apt timer switches. There's no control over sink vs bath element. The timer switch is in the hot press itself rather than outside - not sure if I read somewhere previously that this is considered bad practice?

Just wondering if there are any safety concerns with replacing the Apt timer directly with, for instance, FSTWIFI Wi-Fi Controlled Fused Spur to enable remote control, scheduling etc?

https://www.timeguard.com/products/time/immersion-and-general-purpose-timeswitches/wi-fi-controlled-fused-spur

limnam

AstraMonti wrote: »

Nothing to do with pay, it appeared to me that it is a hard limit on the software, for whatever reason.

Strange alright

deezell

keane2097 wrote: »

Hi folks, my immersion is currently controlled by one of the standard Apt timer switches. There's no control over sink vs bath element. The timer switch is in the hot press itself rather than outside - not sure if I read somewhere previously that this is considered bad practice?

Just wondering if there are any safety concerns with replacing the Apt timer directly with, for instance, FSTWIFI Wi-Fi Controlled Fused Spur to enable remote control, scheduling etc?

https://www.timeguard.com/products/time/immersion-and-general-purpose-timeswitches/wi-fi-controlled-fused-spur

Just check the ratings on your immersion. You imply it is a dual immersion, with sink/bath switch. See can you read the wattage or current consumption in Bath mode on the immersion casing .The FSTWifi is rated at 13A, A 230v 3Kw element is right on the limit of this. I would be a little uncomfortable with the switch working at its current limits.

I just set up my nest last night and have a quick question about the scheduling ,

If I set the temp at 20 degrees at 7am ,
Is that come on at 7am and rise to 20
or
Be at 20 at 7am?

Thanks

ted1

BrownFinger wrote: »

I just set up my nest last night and have a quick question about the scheduling ,

If I set the temp at 20 degrees at 7am ,
Is that come on at 7am and rise to 20
or
Be at 20 at 7am?

Thanks

It’ll be 20 degrees at 7am. But it may take a few days to learn how long the house takes to heat up it’ll also come on and off randomly during this learning phase.


The above requires True Radiant to be On in the app

keane2097

deezell wrote: »

Just check the ratings on your immersion. You imply it is a dual immersion, with sink/bath switch. See can you read the wattage or current consumption in Bath mode on the immersion casing .The FSTWifi is rated at 13A, A 230v 3Kw element is right on the limit of this. I would be a little uncomfortable with the switch working at its current limits.

Hi deezell, thanks for the info. I had actually meant to imply the opposite!

There is no switch for sink/bath in my hot press so my guess is it's a single element. I'll have a good poke around this evening and see if I can confirm.

un5byh7sqpd2x0

Howya,

My heating system consists of a combi-boiler for the water - no hot water tank - and 2 zones for the heating with a stat in each zone, upstairs and downstairs. I'm interested in installing Nest to control the system. What do I need to get? I assume 2 stats and a heatlink? Does each stat come with a heatlink?

Learning Thermostat or Thermostat E?