Hub Controller options

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.

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?

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.

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.

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

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.

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.

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

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.

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

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.

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.

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.

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

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

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.

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.

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