Home heating automation

deezell

Vikings wrote: »

Hi folks I've another what smart thermostat to buy post if anybody has any advice for me. Just moved house and want to upgrade the heating controls asap. Had previously used a single nest in previous house but thinking bigger.

There's 10 rads in the house in total. 7 currently have TRVs fitted (excluding 2x bathroom and a vertical rad in kitchen)

The current controller has CH and HW only - and somehow can't figure out how or why I can't just get the CH to work without the HW too.....

This is likely because your system is plumbed for gravity heating of the HW, and pumped heating of the CH. In this arrangement there are no zone valves, and the 2 zone controller uses a different logic. The controller will have to have a gravity mode switch or jumper, and in this mode, the HW terminal goes live for either HW or CH timed events, while the CH terminal goes live for CH events only. The HW terminal directly fires the boiler, so ALL events heat HW by gravity. The CH terminal only connects to the circulation pump, so when a CH event occurs, the pump comes on and shifts the heated flow to the rads, from the boiler which has been fired by the HW terminal.
To have fully pumped mode, with CH and HW independence, your system would need zone valves to isolate either flow, then your controler would be set to operate in Fully Pumped Mode, with each terminal on the controller going live only for it's own timed event.

The Tado ext kit has a software setting to enable gravity mode, the newer version has double pole relays for each zone which can be cross wired to enable gravity mode.
The Nest Heatlink box can be wired likewise.
The Hive HW+CH receiver can be configured in gravity mode.
The Drayton wiser 2 zone controller can not be configured in gravity mode, and can only switch independent zone valve systems.

Have a look to see what devices are in your circuit. Its possible you have zone valves if its a new or recent build, but the HW valve is either stuck open or locked open. This would cause HW to be on for any CH timed event.

deezell

Amazon De are a few guid cheaper for starter kits, the wired kit is €147, €157 with our Vat and postage, €43 less than Tado /ie shop. No exchange or duty.
https://www.amazon.de/-/en/4260328611456-tado%C2%B0-Smart-thermostat/dp/B07FZ3P393

chris_ie

deezell wrote: »

You should have at least one radiator open, and preferably before the zone valves. When the stove output exceeds the capacity of the HW cylinder to sink heat by gravity, the stove stat will close and turn on the stove pump. This will circulate the stove heat to any open rads in open zones.
If all the rads have closed trvs, and all the zone valves are closed, this would prevent any rad dissipating the heat from the stove. Its moot to ask why a stove would be burning when there was no requirement for CH and the TRVs are all closed. What's required in this case is an open rad before the zone valves, or a relay triggered from the stove stat to open at least one zone. A lex or wiring box can be used to simplify mixed heat source systems, with a two pole relay used to turn on a zone valve or pump, and to mute the oil boiler call while the stove is producing excess heat. In such a system you would require a few open rads, or at the least to be running a schedule for the TRVs that would has some on call during the time the stove is burning.
Again, TRVs do not suit a mixed source system as the possibility exists of all rads closed due to low temperature schedule, while someone lights a stove and cranks it up. Just using the stove stat to relay open a zone valve is not enough, if there are no open rads on this zone.

Thanks deezell. Yeah I was thinking about when we’d have the stove on to heat the house, then rooms reach their set temperatures and close of. If not rads in a zone were lower than their desired temp, I thought the zone valve would then close? I may be wrong here? Then this is where I could see an issue.

I would leave a few rads in each zone open butte the zone valve closed this doesn’t help.

I know it’s not ideal using these systems with dual heat sources but I figured it was doable. You had mentioned the wiring to cut the boiler call when stove heat is sufficient which sounded good.

If there was such a way that you could set the temps in the rooms for a schedule but not have them call for heat, meaning stove heat would be used, it would be handy but I haven’t read the wiser it tado manuals yet to check that out.

Just out of curiosity, would you advise against using these systems with dual heat sources?

deezell

Just have a couple of open rads. With Tado, you can schedule TRVs off grid, they will open but not call the boiler, just like a manual TRV. They'll still close though on hitting target. Technically a TRV is incompatible with an unregulated heat source, if the souce increases output greater than is necessary to bring the room to target temperature, the TRV does the exact opposite of a heat sink, by closing when it most needs to be open. My dual system is zone pumped, not valved. The stove stat turns on the ch zone pump, open rads heat the space, sometimes past the Tado stat setting, except in the kitchen which has a TRV. It would need to be blazing, or mild weather for it to heat past the schedule setting, but it does occasionally.

Vikings

deezell wrote: »

This is likely because your system is plumbed for gravity heating of the HW, and pumped heating of the CH. In this arrangement there are no zone valves, and the 2 zone controller uses a different logic......

Have a look to see what devices are in your circuit. Its possible you have zone valves if its a new or recent build, but the HW valve is either stuck open or locked open. This would cause HW to be on for any CH timed event.

Thanks for taking the time for this - I've a better understanding of the system now. House was built around ~2000 so not new & not old either!

I've had another look at things and can see I've a Horstmann Centaurplus C27 programmer which controls things. I noticed a separate switch within the hot press which can switch off the CH aspect from working via the controller.

I don't think there are zone valves but I'll admit I'll need to take another look this evening to be sure.

Having watched an install video or two on the Tado system it looks fairly straightforward to fit. And also easy to add smart TRVs at a later date.

If you could answer another question for me re the Tado. If I was to install the starter kit with their TRVs I will have control similar to how my best used to work - whole house 1 temp? And if I add their TRVs I can have some control over each room it is in. If I do that, how do the rooms with no TRVs react to the settings? Will those rads go full blast?

deezell

Vikings wrote: »

Thanks for taking the time for this - I've a better understanding of the system now. House was built around ~2000 so not new & not old either!

I've had another look at things and can see I've a Horstmann Centaurplus C27 programmer which controls things. I noticed a separate switch within the hot press which can switch off the CH aspect from working via the controller.

I don't think there are zone valves but I'll admit I'll need to take another look this evening to be sure.

Having watched an install video or two on the Tado system it looks fairly straightforward to fit. And also easy to add smart TRVs at a later date.

If you could answer another question for me re the Tado. If I was to install the starter kit with their TRVs I will have control similar to how my best used to work - whole house 1 temp? And if I add their TRVs I can have some control over each room it is in. If I do that, how do the rooms with no TRVs react to the settings? Will those rads go full blast?

You can pop off the controller to see if its operating in gravity mode. Read page 3 of the installation sheet here.
https://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/C21_I.PDF
If the blue link mentioned is removed, its in gravity mode.

Partial TRV installation will operate the heating for open rads also on a single zone system. It's useful nonetheless, as a means of reducing heat to selected rooms when not needed, bedrooms and lounge in daytime, kitchen later on etc. Also useful for cold rooms which might cool quicker than the general set temperature of the main stat.your existing mechanical TRVs will cap rooms not fittex with smart TRVs when the smart calls the boiler.

chris_ie

deezell wrote: »

Just have a couple of open rads. With Tado, you can schedule TRVs off grid, they will open but not call the boiler, just like a manual TRV. They'll still close though on hitting target. Technically a TRV is incompatible with an unregulated heat source, if the souce increases output greater than is necessary to bring the room to target temperature, the TRV does the exact opposite of a heat sink, by closing when it most needs to be open. My dual system is zone pumped, not valved. The stove stat turns on the ch zone pump, open rads heat the space, sometimes past the Tado stat setting, except in the kitchen which has a TRV. It would need to be blazing, or mild weather for it to heat past the schedule setting, but it does occasionally.

Yeah the plan at the minute is that I'd have a few open radiators in each zone without TRVs. Going to be fun trying to get an electrician who can wire this up right. You're not in Donegal by any chance deezell? I could leave the zone valves open and let the TRVs do the 'zoning' but then when stove isn't in use it'd be heating/pumping some places unnecessarily.

deezell

chris_ie wrote: »

Yeah the plan at the minute is that I'd have a few open radiators in each zone without TRVs. Going to be fun trying to get an electrician who can wire this up right. You're not in Donegal by any chance deezell? I could leave the zone valves open and let the TRVs do the 'zoning' but then when stove isn't in use it'd be heating/pumping some places unnecessarily.

What I wouldnt give for a few days in Dungloe, or Letterkenny. I haven't left Kildare for a year now, except back and forth to the city a few times.
There's not much to the wiring, but a lex or wiring box will have all the relays you need to implement muting of oil and opening of zone valves by the stove stat. Nrg awareness do a lex box, https://www.nrgawareness.com/product/nrg-lex-v2-system-control-module/
Here's a good description if the one Systemlink do,
https://www.systemlink.ie/systemlex.html

DrPhilG

chris_ie wrote: »

You're not in Donegal by any chance deezell?

I reckon I'd have nabbed him for a visit if he was lol.

I bit the bullet and grabbed another 3 pack of Wiser stats. That'll take me up to the 13 I need to finish the job.

I've been building them up over the last few months.

chris_ie

deezell wrote: »

What I wouldnt give for a few days in Dungloe, or Letterkenny. I haven't left Kildare for a year now, except back and forth to the city a few times.
There's not much to the wiring, but a lex or wiring box will have all the relays you need to implement muting of oil and opening of zone valves by the stove stat. Nrg awareness do a lex box, https://www.nrgawareness.com/product/nrg-lex-v2-system-control-module/
Here's a good description if the one Systemlink do,
https://www.systemlink.ie/systemlex.html

That looks a handy job. Another item for the shopping list most likely! So any decent electrician should be able to sort the system with one of those.

I’m assuming if a room called for heat and the stove pipe thermostat fired the pump then the oil wouldn’t be called, but if the room wasn’t heated to its desired temp once the pump stopped the oil would kick in. All of this would be seen by the Tado/Drayton as the oil being fired so the historical data wouldn’t show true oil usage or whatever. Not a big deal though.

DrPhilG wrote: »

I reckon I'd have nabbed him for a visit if he was .

Phil do you know if the Drayton has an off grid kinda setting like deezell mentioned the Tado has? Where it wouldn’t call for heat but would still close at the trv temp setting?

DrPhilG

chris_ie wrote: »

Phil do you know if the Drayton has an off grid kinda setting like deezell mentioned the Tado has? Where it wouldn’t call for heat but would still close at the trv temp setting?

No idea, sorry!

Vikings

deezell wrote: »

You can pop off the controller to see if its operating in gravity mode. Read page 3 of the installation sheet here.
https://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/C21_I.PDF
If the blue link mentioned is removed, its in gravity mode.

Partial TRV installation will operate the heating for open rads also on a single zone system. It's useful nonetheless, as a means of reducing heat to selected rooms when not needed, bedrooms and lounge in daytime, kitchen later on etc. Also useful for cold rooms which might cool quicker than the general set temperature of the main stat.your existing mechanical TRVs will cap rooms not fittex with smart TRVs when the smart calls the boiler.

Thanks again - after looking again it's the C21 there currently as the controller. There is something blue in that spot on the rear of the controller but I'm not sure if there was something additional covering it previously? If I've explained that properly.

If I was to buy the tado starter kit - am I right to say I want the wired starter kit and also the extension kit for the water. Replace my C21 with the extension kit and replace wall thermostat with the tado smart stat. And then any/all trvs.

deezell

Vikings wrote: »

Thanks again - after looking again it's the C21 there currently as the controller. There is something blue in that spot on the rear of the controller but I'm not sure if there was something additional covering it previously? If I've explained that properly.

If I was to buy the tado starter kit - am I right to say I want the wired starter kit and also the extension kit for the water. Replace my C21 with the extension kit and replace wall thermostat with the tado smart stat. And then any/all trvs.

The mode link is a small blue blue jumper plug. I see what you're saying, it migh already be unplugged, leaving a similarly coloured receptacle. If you can't see an obvious small plug that you can grip and remove, if there is just a fixed socket receptacle with either pin holes or pins sticking out, then I'd assume it's already plugged out, and your controller is in gravity mode, with CH timer terminal 4 just controlling the pump, while the HW On teminal 3 fires the boiler for both CH and HW settings. Your Tado ext kit will replace this controller, it will have to be configured in gravity mode if that's what you have, which sounds likely for a circa 2000 build. Look again at the blue link, or its socket, post image if you can.

You'll need what is known as the wireless starter kit, this incudes the ext kit, and if you don't already have a wired wall stat, you can connect the Tado stat wirelessly back to the ext kit. TRVs the next bit. If you want CH without HW, you'll need to add zone valves, but its not a biggie, HW is unlikely to overheat when the boiler is delivering heated water to the rads for CH, especially with the Tado, as it modulates the boiler burn for a cooler flow once the CH is near it's scheduled temperature.

deezell

Tado Wireless starter kit from amazon .de for about €40 less than tado /ie
https://www.amazon.de/-/en/4260328611456-tado%C2%B0-Smart-thermostat/dp/B07FZ3P393

sebdavis

deezell wrote: »

Tado Wireless starter kit from amazon .de for about €40 less than tado /ie
https://www.amazon.de/-/en/4260328611456-tado%C2%B0-Smart-thermostat/dp/B07FZ3P393

No drayton deals knocking around :-)

Vikings

deezell wrote: »

The mode link is a small blue blue jumper plug. I see what you're saying, it migh already be unplugged, leaving a similarly coloured receptacle. If you can't see an obvious small plug that you can grip and remove, if there is just a fixed socket receptacle with either pin holes or pins sticking out, then I'd assume it's already plugged out, and your controller is in gravity mode, with CH timer terminal 4 just controlling the pump, while the HW On teminal 3 fires the boiler for both CH and HW settings. Your Tado ext kit will replace this controller, it will have to be configured in gravity mode if that's what you have, which sounds likely for a circa 2000 build. Look again at the blue link, or its socket, post image if you can.

You'll need what is known as the wireless starter kit, this incudes the ext kit, and if you don't already have a wired wall stat, you can connect the Tado stat wirelessly back to the ext kit. TRVs the next bit. If you want CH without HW, you'll need to add zone valves, but its not a biggie, HW is unlikely to overheat when the boiler is delivering heated water to the rads for CH, especially with the Tado, as it modulates the boiler burn for a cooler flow once the CH is near it's scheduled temperature.

I've attached a pic of the blue piece in that spot as attached - after looking again it might still be in place. So I've also attached a picture of the system in the hot press which might explain some more to you (can I send you money for a coffee by the way! Should be charging for this help)

Either way I've gone ahead and ordered the wireless v3 kit from amazon de, should be here by the weekend and I'll look at setting it up then. There is a wired wall stat downstairs. I'm thinking I'll buy 8 tado TRV's once I get set up and move 2 of the current regular TRVs to the bathrooms that have nothing in place and that gives me something on every rad.

Would you go to the trouble of adding zone valves given this set up? I think I get what you are saying regarding the HW and CH - any time we look for CH there will also be HW but as the boiler is already firing for the CH it won't be using much additional energy to have the HW also?

deezell

That looks like the blue link is in place, so the controller is configured for 'fully pumped', with independent live out for each zone, CH and HW. Normally the outputs are used to close zone valves, whose relays then close and the combined relay live outs fire the boiler and operate the pump. To this end, you seem to have at least one zone valve, for CH. I'm guessing it's relay is combined directly with the HW live from the controller to fire the boiler for either timer, but HW will heat for either as it is not valved. It does however appear to have a temperature regulation valve on the hot flow, which would restrict the temperature of the cylinder HW.

The ext kit is just a straight swap for the controller, you can wire the stat in place of the old one, or use it wirelessly in a new location, and just turn the old stat up full, or remove and short out COM and NO wires

DrPhilG

Ready to roll!

chris_ie

DrPhilG wrote: »

Ready to roll!

Good luck!

Jees, looks like you have the same windows as me too!

DrPhilG

chris_ie wrote: »

Good luck!

Jees, looks like you have the same windows as me too!

I feckin hate those stupid windows with the wee bars in them, Georgian bars or something?

sebdavis

DrPhilG wrote: »

Ready to roll!

How much they all cost in the end if you dont mind me asking?

DrPhilG

sebdavis wrote: »

How much they all cost in the end if you dont mind me asking?

All in, system plus 2 room stats plus 15 TRVs, bit under €680 in total.

Got some of the TRVs in a 3 pack, got a good few others second hand.

Whole lot full price would be €800 ish.

Plus installation of course, which was fairly minor as I had both plumber and spark doing some other work too.

sebdavis

DrPhilG wrote: »

All in, system plus 2 room stats plus 15 TRVs, bit under €680 in total.

Got some of the TRVs in a 3 pack, got a good few others second hand.

Whole lot full price would be €800 ish.

Im trying to pick up the TRV's now.....the 3 pack was reduced in price and I missed it need to wait now

DrPhilG

sebdavis wrote: »

Im trying to pick up the TRV's now.....the 3 pack was reduced in price and I missed it need to wait now

In fairness it was only down by £5 for a 3 pack, so a pretty minor saving.

sebdavis

DrPhilG wrote: »

In fairness it was only down by £5 for a 3 pack, so a pretty minor saving.

Im a Cavan man.....thats a lot of money for a cavan man!!!!

Paulzx

DrPhilG wrote: »

All in, system plus 2 room stats plus 15 TRVs, bit under €680 in total.

Got some of the TRVs in a 3 pack, got a good few others second hand.

Whole lot full price would be €800 ish.

Plus installation of course, which was fairly minor as I had both plumber and spark doing some other work too.

I've all my downstairs rads fitted with Drayton TRV's. I originally started with the 2 zone and hot water thermostat kit for a few months. I've found the downstairs thermostat is now more or less redundant since i fitted all the rads with the smart TRV's.

I still have standard non smart TRV's upstairs with the zone controlled by the Drayton Thermostat.

I wonder can any long term users of the system give me another reason for still needing the Thermostat on the zone that is fully fitted with Drayton TRV's?

booooonzo

I have a honeywell evohome kit
bdr91
wireless controller
hot water kit
12 x HR92

I am installing a new cylinder and heating system and wanted to guide the plumber as to the best layout. he has never installed one before.

Do i just continue with a basic S or y plan and install on that or is having multiple motorized valves also necessary?
I assume I don't need the zone programmer or any of that.

It will be upstairs and downstairs layout with separate hotwater

What is the best approach for a new install or has anyone gone that route that could offer some guidance.

eventually it will be new oil boiler direct to a new unvented cylinder and from there of to the rads or hw

Is it still worth or necessary to zone the house with the 2 port valves?

thanks

deezell

booooonzo wrote: »

I have a honeywell evohome kit
bdr91
wireless controller
hot water kit
12 x HR92

I am installing a new cylinder and heating system and wanted to guide the plumber as to the best layout. he has never installed one before.

Do i just continue with a basic S or y plan and install on that or is having multiple motorized valves also necessary?
I assume I don't need the zone programmer or any of that.

It will be upstairs and downstairs layout with separate hotwater

What is the best approach for a new install or has anyone gone that route that could offer some guidance.

eventually it will be new oil boiler direct to a new unvented cylinder and from there of to the rads or hw

Is it still worth or necessary to zone the house with the 2 port valves?

thanks

You wont need to zone the CH, but you will need a zone valve on the HW flow circuit if you want to independently control HW temperature. You should have 2 BDR91 receiver relays, one for all instances of CH calls from the controller stat and the TRVs. The other for calls from the HW thermostat kit. The HW relay will control the HW zone valve, whose built in relay will fire the boiler. This live out is combined with the live from the CH BDR91, together they fire the boiler for either HW or CH. If all rads are fitted with Evohome TRVs, then there is no requirement for a CH zone valve or it's relay.
It's all in here, the diagrams show a single valve installation under Y plan, but do not reference the wiring required to activate the boiler for CH only. This would require the CH BDR91, as shown in the S plan.
https://heatingcontrols.honeywellhome.com/Documents/All/pdf/evohome-installation-guide-(2020).pdf

booooonzo

deezell wrote: »

You wont need to zone the CH, but you will need a zone valve on the HW flow circuit if you want to independently control HW temperature. You should have 2 BDR91 receiver relays, one for all instances of CH calls from the controller stat and the TRVs. The other for calls from the HW thermostat kit. The HW relay will control the HW zone valve, whose built in relay will fire the boiler. This live out is combined with the live from the CH BDR91, together they fire the boiler for either HW or CH. If all rads are fitted with Evohome TRVs, then there is no requirement for a CH zone valve or it's relay.
It's all in here, the diagrams show a single valve installation under Y plan, but do not reference the wiring required to activate the boiler for CH only. This would require the CH BDR91, as shown in the S plan.
https://heatingcontrols.honeywellhome.com/Documents/All/pdf/evohome-installation-guide-(2020).pdf

Thats great, thanks very much for you help

loyatemu

Paulzx wrote: »

I've all my downstairs rads fitted with Drayton TRV's. I originally started with the 2 zone and hot water thermostat kit for a few months. I've found the downstairs thermostat is now more or less redundant since i fitted all the rads with the smart TRV's.

I still have standard non smart TRV's upstairs with the zone controlled by the Drayton Thermostat.

I wonder can any long term users of the system give me another reason for still needing the Thermostat on the zone that is fully fitted with Drayton TRV's?

can you link the external thermostat to one of the TRV, so you're measuring the temp from somewhere else in the room (I only have the basic kit, no TRVs)

what happens when all the TRVs in a zone are at the set temperature, does the zone shot off at the main valve?