Hub Controller options

crazydude

Hi Guys

So my system never had a thermostat just a time clock in kitchen. I got a Hub Controller as it gave me a stat allowing me some control. But as others said I have no intension of paying a monthly fee.

So I had a look at my system and a good read of all the posts above with a view to upgrading.

I have oil boiler and I have a mixture of thermostatic valves and ordinary valves in house. I also have an immersion with motorised valve in airing cupboard I assume allows the hot water in tank to heat separately.

So I have a few questions on the smart systems like Tado I would appreciate if someone (deezill? :) ) could answer.

1. If I put in TRVs am I right that they can be fitted to the existing thermostatic valves without the need to drain system? However for rads with ordinary valves I need to drain, fit thermostatic valves then TRVs on top?
2. TRVs act as a "Room Stat" allowing each Room to be "zoned"... Correct?
3. If I fit TRVs to all rads what is the purpose of the wireless thermostat then? It is not just duplication?

Thanks for reading

deezell

1. Yes

2. Yes, but see 3.

3. Smart TRVs on their own can't connect to the boiler to call for heat. There needs to be at least a receiver relay or a wired main stat to do this on their behalf. Generally, if this is in the hall or kitchen, it's co-located radiators would not have a TRV. Other rooms or zones whose TRVs open for heat will call the boiler by using the main stat as a relay. The calling TRV room and all open rads will also heat during this event. If you only have partial smart TRV install, it's real benefit is in closing off unwanted zones at specific times. If you wish to close off heating in the main stat location while allowing it to close its relay to fire the boiler for TRV calls, you can fit a TRV in the main stat location and slave it to the main stat, using it's zone schedule and temperature sensor. The TRV in this instance is just a motorised valve. A call from another TRV will operate the main stat relay to fire the boiler, but will not open the slaved TRV, thus not heating the main stat location until its own zone schedule activates it.

crazydude

Thanks for reply, sorry I have a few more questions...

So in my instance my Hub controller is in the Kitchen so this is where I connect my receiver but as the kitchen is not ideal for the stat I was going to locate this in my (large) living room. Here I have 3 rads with 3 thermostatic valves. So I should maybe open them fully and let the stat control room temperature?

Then in bedrooms hall, landings etc. (upgrade if required) fit TRVs and programme them as zones.

Also I forgot to ask, can I control the immersion also? and then I buy the "Heating and Hot Water" Tado? If so how do I get this to control tank temp? as I said I have a stat and motorised valve in airing cupboard already.

and finally when all this is done and programmed I power up boiler and let system take over turning on and off heating? Now we usually use the boost control on the Hub (sometimes timer) and keep boiler turned off at all other times.

deezell

Yes, you connect the receiver in place of the Hub. This could be the receiver of any of the smart Stat systems which have TRV options, Tado, Hive, Drayton Wiser and others.

Did you have seperate HW control on your previous timer before Hub was installed, was it a two zone timer. If so, and you no longer have seperate timer control of HW, how do you currently heat HW. Does it heat from the oil boiler when CH is on?

crazydude

No I did not and single zone timer just switching on boiler.

I heat from boiler when CH is on or in summer I switch on immersion

deezell

You'll need to determine what that motorised valve does in the hot press. Its more likely that its used to close off the CH when its not active rather than to isolate the flow to the HW tank. You'll also need to see if is controlled by any source, as in, where does the brown live wire to it go. Is the motorised valve relay (grey and orange wires) connected to any circuit. Does the valve open and close during CH, or is it latched open. Only then can you determine if it is in fact there to close CH flow, allowing a separate call to the boiler from a HW relay in the receiver to heat HW only from the oil boiler.

Its unlikely that there are additional wires in the wall under the Hub that may have been there to allow independent switching of HW, you could take a look though. If you site the receiver here, it might make it difficult to access the HW relay terminals in the receiver when you try to connect up to the zone valve. Take a few images of this valve, and the pipework around it, any boxes where it's cable goes, the wiring behind the Hub. It might help to make sense of your setup.

crazydude

will do... I do know there are no additional wires around hub... it is a simple L/N supply and Switch Wire

From memory the valve is fed from a supply that comes from immersion supply and controlled by stat a strapped to copper tank. But I'll get some images later when home.

crazydude

Here we go 😉

deezell

The Valve is on the hot flow inlet of the cylinder, it's there to zone the HW in some manner. It's currently activated as the pilot light is lit. The cylinder stat is turned up full, which means the valve is always open. You've said the live into the cylinder thermostat is tapped off the electric immersion live. You haven't looked to see if the relay wires from the valve cable, grey and orange, are supplied with live or connected to any other cables. Is there a small junction box present where all the cables converge? This looks like half of an S plan two zoned valved system, but in that case there should be another zone valve on the CH circuit. I can only think if one reaon for a valve only on the HW flow in, and that might be to prevent loss of HW to the CH by gravity,if the cylinder is below upstairs radiators, as when the boiler is off, the HW cylinders will act as a gravity feed to radiators above it if the cylinder flow and return are tapped off the risers from the boiler to the upstairs rads. You definitely don't want this to happen if you're heating HW by the electric immersion element. Is the house two story, and if so is the cylinder downstairs?

Btw, when you refer to 'controlling the immersion' in your post, I'm not sure if you're referring to heating the HW cylinder from the boiler, or by the electric immersion element in the cylinder. Sometimes the HW cylinder is referred to generically as ' the immersion'.

Also operate the cylinder stat. Turn it down and see does this close the valve and turn off the pilot light. This could be used to prevent the cylinder overheating in the event the hot flow being at a substantially higher temperature than required. This is only likely to occur if all the radiators are off, but the boiler is called by the old timer/ new Hub. Whatever was intended, it's unconventional. If the relay on the valve was used to call the boiler, and if the CH also had a valve in it's flow, operated by the hub with its relay output combining with the cylinder valve relay output to the boiler, then you would have a classic S plan with 2 independent zones, HW called by the cylinder stat and CH by the Hub C. Instead it looks a like a 1.5 zone system, which consusts of one valve only on the CH, usually controlled by a walk stat, with the boiler fired by a timer, giving you both CH+HW, or HW only when the stat is turned down. What you have is an odd reverse of this, and in its current form it does not facilitate heating HW only from the boiler, unless there is some way stop the hot flow to the CH circuit while the boiler is firing.

Also check for certain that the valve remains open and lit regardless of whither the CH is on or off, and regardless of whether the electric immersion is on or off.

crazydude

OK just managed to talk to plumber that installed the valve and he explained it

My house is an old house with a single circuit system doing upstairs, downstairs and hotwater.

What the valve is for is when the copper cylinder water reaches 65 degrees (my stat was set to wrong temperature and must of got moved so fixed that now) it shuts the valve stopping the CH heating the hot water further until temp in cylinder drops again.

Anyway so it answers my question and I just require a heating only controller.

Thanks so much for having the patience to answer my questions and taking the time to do so.

Banjo Carney

My system is single circuit also doing upstairs downstairs and hot water but it doesn't have a stat to prevent the water in the copper cylinder going above a set temp.

Should it ?

crazydude

all I can say is the plumber I spoke to said it was a measure to save on costs as you don't always be heating the hot water in cylinder while heating is on.

deezell

It would be unlikely to exceed 65° as the boiler flow occurs only when the CH is on, so the hot flow will be unlikely to reach the boiler set temperature, generally about 69 to 70° for efficiency, unless all the radiators are manually turned off.

If you're replacing the Hub with the Tado, it's receiver has both CH and HW relays. You could ask your plumber to see if your CH flow can be split from the HW flow, which would allow an S plan two valve system. If the CH circuit is not tapped entirely before the HW circuit, then it would not be possible without replumbing. That said, it won't stop you fitting the receiver in place of the Hub. This will allow you to locate the wireless stat in the living room, and yes, you can open the three rad TRVs as the stat will govern the room temperature. The HW relay will be there if needed should it be possible to add an extra motorised valve to close off CH while HW is open. In many cases the hot flow is split straight after the boiler, with a direct run to the cylinder, and a separate run for the CH.

deezell

https://www.boards.ie/discussion/comment/119972431#Comment_119972431

For the same reasons I gave @crazydude, the cylinder will only exceed a safe temperature if the flow temperature is a lot higher that 60 to 65°. This depends on the temperature that the boiler is set to, and how close to this the flow gets, given that its being cooled by all the radiators. In a normal system with independent flows, the HW stat on the cylinder would interrupt the boiler and close its own zone valve when HW temperature is reached. When CH comes on, it will actually initially cool an unvalved cylinder until the flow temperature rises close to the existing HW temperature. If the boiler is set to say 68°, it is highly unlikely to reach this unless very few rads are open, and you don't have a system where the boiler is firing for hw only, plus the heat transfer to the HW will be very slight as the HW heats to only a few degrees cooler than the flow, as the heat transfer is proportional to the difference.

crazydude

I figure for about €700 ish investment I can make my system "smart" and save a lot more and have a more comfortable warm envoirment when and where I need it. This will be my project in new year 🙂

deezell

https://www.boards.ie/discussion/comment/119972725#Comment_119972725

Go for it. This Tado kit for the first part only €119, and a diy install. A few hundred for TRVs next.

https://www.screwfix.ie/p/tado-v3-black-edition-wireless-heating-hot-water-smart-thermostat-starter-kit/701kg

Banjo Carney

@deezell thanks you're a mine of information

crazydude

I looked at that but as I am not doing hot water is that not what I get? or does it matter?

deezell

https://www.boards.ie/discussion/comment/119972826#Comment_119972826

Doesn't matter, you just don't use the HW terminals

crazydude

I think I found a solution on how to control the immersion cylinder

If I install a Wiser Electric Heat Switch (https://wiser.draytoncontrols.co.uk/electrical-heat-switch-and-remote-floor-temperature-sensor) to the immersion I can then make the immersion a zone and set it to come on via app etc.

Means my system will be a wiser system

deezell

https://www.boards.ie/discussion/comment/119973809#Comment_119973809

Just the heat switch. The immersion element has its own built in thermostat switch to limit the water temperature. You can time the immersion element with this from the wiser app.

crazydude

Perfect

I'll get ordering today

Again thanks for all your help!!

extrafluff

Hi all,

There's one of these in my house, previous owners had gotten this installed. The battery is low on this & keeps knocking off and turning my heating off. I had an issue with my heating last week and had to get the plumber to bypass the standard time clock.

My question is can this be removed easily or do I need to get an electrician to come out to remove it?

Thanks

deezell

https://www.boards.ie/discussion/comment/120017267#Comment_120017267

These things have a built in rechargeable battery if there was no full mains at the point they're located (if it replaced an old mechanical wall stat which switched a two wire live in and out but didn't have a neutral wire in the wall box). It was kept charged by a parasitic low current draw from the live it was switching, but this possibly depends on the circuit being open and the boiler off for a decent percentage of the time, otherwise the battery can't stay charged. Rechargeable Battery is probably ageing too, it would be soldered in circuit and not worth paying for a replacement.

Once you figure how to unclip the unit off its base, you can replace it with a proper wired smart stat such as a Tado, which uses AAA batteries that last over a year. If you're not comfortable with DIY on a pair of wires connections similar to a single wall light switch, get someone in to do it. If you get the unit unclipped, check to see if its only two wire connection.

Aquos76

@deezell

Can I pick your brains please, twice over Christmas I had an issue whereby I boosted my heating for an hour each time and I noticed that when the hour lapsed the heating never switched off and when I went to the unit at the boiler the triangle light was lit up, along with the normal lights, power light, wifi light and heating light when on. When I checked the tado app, its back in schedule mode and as far as the app is concerned, the heating is off.

I've googled the triangle light and it just says device errors, but Ive no idea what the error could be. Have you come across this issue before?

deezell

It looks like the ext kit is losing connection to the Bridge. As a consequence the device remained at the last setting until it reconnected. If you can replicate this fault, in the app go to Settings/Rooms & Devices and see if the ext kit is showing a symbol to indicate it's offline. Over the years a few people have reported some devices dropping out.

Some users have used WiFi repeaters with an ethernet socket as a means of locating the bridge away from the router to an optimal position for connecting to stats, TRVs and the Ext kit. Running the bridge from a WiFi connected device might slow down the response of the app to changes in temperature readings and control of stat relays and TRV valves, as a lot of these little extenders are half duplex devices, with more latency in sent and response data. If it's a connection problem, as against a firmware or hardware issue in the ext kit, you could try this with the bridge, or as a simpler solution, use a longer ethernet cable to allow a higher or closer placement of the bridge.

In an odd coincidence, I've had a full loss of Broadband since Friday, a break in my cable to the fibre cabinet 700m away, no hope of a repair before Tuesday. My heating continued to work, but stuck on its last thermostat scheduled setting as Tado app went offline.

Without automatic return to schedule, the boiler was flat out as each manual boost went untimed. I dug out an old plugin WiFi repeater which has an ethernet socket, paired it to a hotspot off my mobile data, and plugged the bridge in. It restored the app and schedule, but one TRV struggled to reconnect until I physically disconnected it and moved it nearer the bridge.

My bridge bodge pictured below.

Aquos76

I was actually thinking this might be the problem ok. I do have a deco mesh hub system in the house and have a mesh which is closer to my utility room than where the bridge is currently at the main mesh unit. I might connect up a switch to the hub and see will that solve the issue. Thanks for that.

Banjo Carney

I got great advice here before Christmas and I installed a Tado.

My son also has a hub controller which he wants to replace. As he's only renting all he wants is a smart thermostat he can control with an app.

Does anyone know of one or where he could get it. Thanks in advance.

wheres me jumpa

Thanks everyone for the tado recommendation and advice.

Bought in screwfix today and installed in a few minutes. The wiring from hub c is perfect for it.

For anyone wondering the front of the hub just pulls off.

One question for the knowledgeable folks here. Can I wire my immersion to the tado? I don't have separate zones for heating and water.

deezell

https://www.boards.ie/discussion/comment/120126395#Comment_120126395

No. You will need a seperate mains operated relay controlled by the Tado HW relay in order to switch the high immersion element current, typically 13-14A, which would exceed the capacity of the Tado relay and burn out the contacts fairly quickly.

A typical Din rail mounted 20A relay like this below in a suitable small din rail enclosure could be controlled by the Tado HW relay contacts of the Tado wireless starter kit receiver. https://www.meteorelectrical.com/brands/garo/garo-20a-2p-no-modular-contactor.html

deezell

https://www.boards.ie/discussion/comment/120125872#Comment_120125872

Does he not want to fit a Tado? There's not much out there that's Smart and costs less than the current Screwfix wireless Tado Starter kit in Black. HIVE mini for €75 is hard to beat. https://www.screwfix.ie/p/hive-mini-wireless-heating-smart-thermostat-hubless/681pv

There are app accessible wifi capable wall thermostats which will wire up in place of the Hub controller, check amazon for something like this cheap Chinese wired in https://www.amazon.co.uk/Decdeal-Thermostat-Thermostats-Programmable-Temperature/dp/B07S67TV7D/ref=asc_df_B07S67TV7D/

wheres me jumpa

Thanks for the info.

That would be beyond my range of comfort.

Not sure it's worth the hassle either. Only needed in summer and not sure I need detailed control.

Banjo Carney

@deezell thanks once again for your response and info. He wants to spend as little as possible as he's renting and may not be there long more.

I'll show him your suggestions thanks again

Squatman

does anyone know what happens it after today. I havent a notion of paying a subscription. can i manually set times like an old clock timer? id say i will follow deezels advice and install a Tado, interested to see what happens first though

Squatman

@deezell whats the difference between teh 2 tado 1 is 97 the other is 82 both before vat

deezell

I presume these are from the Screwfix site.

First is the wireless starter kit, which has a receiver, AKA as the extension kit, and a wall thermostat, both of which connect by a low power wireless signal to the Bridge, the interface device between all Tado hardware and your Internet. The bridge plugs directly by cable into your Internet router.

The second stat is an add on wired stat, which requires an existing Tado bridge to connect to the Internet, and has a mains voltage relay to directly switch the mains to call the boiler or zone valve.

The wired thermostat is also available in a starter kit, with the bridge, but in Screwfix, only in the normally priced white version at €149 ex Vat.

If you wish to control a HW zone, the extension kit of the wireless starter kit has an additional mains relay to control the HW zone, as well as a wired relay for the CH zone. The actual wall stat of the wireless kit may not have a built in wired relay to directly replace and connect to an existing wired stat location, should you want a wired stat Originally, the same stat was supplied in both kits, with the stat relay configured OFF when connecting via the receiver, to save battery power.

You can also buy the additional sensor stat which has no relay, to use as a sensor for radiator smart TRVs and give more accurate room temperature control.

nava

Hi, I’m looking for some advice too, sorry about it.

Currently as it’s an old house I have only 1 zone, when I switch on the boiler it always heats the water, what I also have by the immersion is a waterlevel, depending on the position open/close when I switch on the the boiler it will also switch heat the radiators.

I’m looking for advice on what my best option will be to prepare for the future, for now that I can install myself but in the future maybe I can upgrade to put on each radiator a thermostat or maybe something to replace that waterlevel, or something else?

hope the above is clear.

regarding the question on what will happen when they start charging, I assume you should still be able to press boost on the device if you disconnect the Hub C from the wifi?

Thanks

deezell

https://www.boards.ie/discussion/comment/120167618#Comment_120167618

With a motorised valve in place of the manual valve, ( the 'waterlevel'?), you can have a two zone system, Hot Water and Central heating. The boiler will be fired by one of two connections. The live output on the HW zone directly from the controller, or else live from the relay of the motorised valve, which in turn is operated by the CH zone of the controller. You can buy a two zone smart system controller such as Drayton Wiser kit2 , Tado Wireless starter or Hive CH and HW. These are selling for about €110 in screwfix. Each of these controller/ receivers connect to their thermostat wirelessly. They also can have smart radiator thermostat valves (about €70) connected so you can control each room from the app. A motorised valve ( about €80) is easy to fit and connect, if you already have a manual valve. The Hub controller can do none of these things, so throw it in the bin.

nava

https://www.boards.ie/discussion/comment/119963155#Comment_119963155

Hi Deezell

Thanks for the advice on your previous post.

Currently I do not have a thermostat, just wonder if you can confirm the connections, in my case I have 3 cables (as on pic below) coming to the Hub Controller, N (Blue), V1 (Black) and L (Brown), from a previous post L and N will connect on the left hand side of the Tado wireless controller, where will I connect the V1? do I also need that purple cable to connect CH/COM with L, Just to remind you my setup is when we switch on the boiler it heats water and radiators, but we have a manual valve, depending on the open/close position when I switch on the the boiler it will also heat the radiators.

Thanks again for the advice and help

deezell

https://www.boards.ie/discussion/comment/120192846#Comment_120192846

L and N to the L and N on the Tado. A short link wire from L to COM on the the Tado CH relay. V1 to thr Normally Open, NO terminal on the Tado ext kit ch relay. The HW relay will come in handy if you get your system fitted with a motorised valve or two you can have seperate heating of CH and HW. I posted an image of the Ext kit wiring a few months back. I'll post it again when I find it. Does that valve give you HW only, or CH only, its not clear the way you describe it.

Banjo Carney

@nava the V1 goes to CH/NO and you need to link L to CH/COM.

My system is similar to yours and how I did it with advice from @deezell he posted a pic on page 1 of this thread

nava

https://www.boards.ie/discussion/comment/120192984#Comment_120192984

Thanks again.

You mean the picture you posted on the 1st of December on post? https://www.boards.ie/discussion/comment/119945516/#Comment_119945516

That picture is what I took as reference on my reply above.

What I have is as in the picture attached, when handle is down it heats water and heating, with handle is up only heats waters. Hope that's clearer now?

Thanks

deezell

https://www.boards.ie/discussion/comment/120193170#Comment_120193170

Yes, Nava just reminded me there also. Sure how can I remember something from two months ago!

A couple of motorised valves on both branches from the big vertical pipe, one in place of the manual valve, and you will have independent HW and CH control. If you have the Tado accessible to wire up to the motorised valves, it would be a simple enough upgrade. Even a single valve on the CH line can be wired to give a 'gravity' style system, with timed control of HW only or CH + HW.

nava

Thanks for all the help, that part looks harder, too much foe my DIY skills, I will get a professional to do it when I decide to upgrade, for now I just wanted to swap the hub Controller with something else.

Thanks

LBF21

Has anyone added a cylinder thermostat to work in addition to Tado? If so how is it working. Not causing issues? Essentially I want to stop the hot water heating when it hit a certain temperature.

deezell

https://www.boards.ie/discussion/comment/120244757#Comment_120244757

Most zoned CH and HW systems would have an electromechanical stat on the cylinder to turn off the HW zone when the set cylinder temperature is reached. If such an installation is upgraded to Tado or other Smart system, only the timing of HW events is controlled by the Tado (or Nest, Hive, Drayton etc). The temperature will still be capped if a tank stat was already installed. If no Tank stat was part of the pre Tado system, one can be installed and used to interrupt the timed live from the Tado to the HW independent zone valve. I say independent, as if the original system was a gravity system, where the cylinder heats during HW or CH timed events, then a stat cylinder will only interrupt HW heating during a HW timed event, but not during a CH event. It is however, unlikely that HW would exceed desired temperature during a CH event as the heating flow will be cooler due to the load from the radiators. Mechanical cylinder stats are simple and inexpensive passive devices. If you desired actual app control of the setting of this temperature, then you are into more complexity, and most smart brands don't offer online control of the HW tank max temperature, there's little point. The Internet equipped EPH Ember controller has a remote thermostat for HW, and the high end Evohome system also but HW max temperature is set and forget, not something you'd need to fiddle with remotely or set on a smart schedule.

LBF21

Thanks for that. We’re not long in the house. Water does be piping, really just want to turn it down a bit. Looks like the previous owners upgraded the boiler as it’s modern enough looking but I can’t see a stat anywhere. BER assessor said we’d go up a rating with a stat.

deezell

You have a Myson valve in your hot press I recall. You have a Tado stat. Do you have the extension kit with timing for hot water? Does this open and close the Myson in the hot press.

LBF21

Great memory! Yep I can control hot water only from Tado.

deezell

https://www.boards.ie/discussion/comment/120249898#Comment_120249898

Then you can insert a stat into the live from the Tado HW relay to the HW Myson valve. I'm assuming you have a two zone valved system with HW only and CH only. If your cylinder is a foam insulated one, you can use a contact stat like this in a cutout in the foam.

If your tank is a metal enclosed one, you can use a probe insert stat like this in one of the provided probe cavities