Smart Thermostat and Smart TRV installation advice

Mount the Wiser backplate at a suitable location near the boiler.

(1) Run a 2-core cable from the N & L terminals on the boiler or from the fused spur that feeds the boiler to the N & L terminals on the Wiser backplate. This could also be a 3-core cable including earth but the Wiser does not require an earth connection itself

(2) disconnect the 2-core cable in 1 & 2 at the boiler which currently goes to the battery powered roomstat.

(3) run a 2-core cable from the boiler 1 & 2 terminals to Wiser terminals 1 & 3.
boiler #1 to Wiser #1
boiler #2 to Wiser #3

Do NOT add any link between L & 1 on the wiser back plate. This is shown as a dotted line in the installation guide.

If you have a 5-core cable even better as that would replace the need for two separate cables from Wiser to boiler. Do not use a green/yellow cpc core for anything except an earth connection.

I have referenced this to assist on the wiring
 
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ian1182 said:
Mount the Wiser backplate at a suitable location near the boiler.

(1) Run a 2-core cable from the N & L terminals on the boiler or from the fused spur that feeds the boiler to the N & L terminals on the Wiser backplate. This could also be a 3-core cable including earth but the Wiser does not require an earth connection itself

(2) disconnect the 2-core cable in 1 & 2 at the boiler which currently goes to the battery powered roomstat.

(3) run a 2-core cable from the boiler 1 & 2 terminals to Wiser terminals 1 & 3.
boiler #1 to Wiser #1
boiler #2 to Wiser #3

Do NOT add any link between L & 1 on the wiser back plate. This is shown as a dotted line in the installation guide.

If you have a 5-core cable even better as that would replace the need for two separate cables from Wiser to boiler. Do not use a green/yellow cpc core for anything except an earth connection.

I have referenced this to assist on the wiring
Click to expand...
This is great. Thank you so much for all the help. I’ll get started on this in the morning. Would putting the hub in the boiler cupboard be suitable or would that be classed as having extremes of heat?
 
joboro said:
This is great. Thank you so much for all the help. I’ll get started on this in the morning. Would putting the hub in the boiler cupboard be suitable or would that be classed as having extremes of heat?
Click to expand...
If possible keep the hub in the open as it needs to use WiFi and zigbee to communicate.
 
Mister Banks said:
If possible keep the hub in the open as it needs to use WiFi and zigbee to communicate.
Click to expand...
I'd agree with that.

To a large extent the distance between your wifi router, thickness/type of walls, etc will determine how well the communication will work. Hence placing the hub in an enclosed location may cause iffy connections. The TRV's are already in difficult areas being low down & next to a metal shield. So you should make it as easy as possible for them to speak to the hub. Note only the hub uses your home wifi, the hub to roomstat/trv communication uses a private zigbee network.

Wiser smartplugs can act as repeaters for the zigbee signal should you experience problems. Unfortunately there is no way to see the wifi or zigbee signal strength for individual devices in the Wiser app. It is possible to get the signal strength by using packet capture to view the data stream between an android phone and wiser hub
 
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ian1182 said:
Mount the Wiser backplate at a suitable location near the boiler.

(1) Run a 2-core cable from the N & L terminals on the boiler or from the fused spur that feeds the boiler to the N & L terminals on the Wiser backplate. This could also be a 3-core cable including earth but the Wiser does not require an earth connection itself

(2) disconnect the 2-core cable in 1 & 2 at the boiler which currently goes to the battery powered roomstat.

(3) run a 2-core cable from the boiler 1 & 2 terminals to Wiser terminals 1 & 3.
boiler #1 to Wiser #1
boiler #2 to Wiser #3

Do NOT add any link between L & 1 on the wiser back plate. This is shown as a dotted line in the installation guide.

If you have a 5-core cable even better as that would replace the need for two separate cables from Wiser to boiler. Do not use a green/yellow cpc core for anything except an earth connection.

I have referenced this to assist on the wiring
Click to expand...
I should have added.

Once all wiring is done you should set the built-in timer to permanently on as that permits the Wiser Hub to control the boiler. I believe there is a 3 position slider (off, timed & on) on the front of the clock
 
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oldbutnotdead said:
Smart trvs require a thinking change.
Click to expand...
Never a truer word. However how smart? The Wiser wall thermostat is really a hub, it accepts commands for heat and adjusts boiler output to suit, or if not OpenTherm then turns boiler on/off.

So I suppose it would go on a wall near the boiler so if it gets too cold and there is a risk of freezing boiler turns on? But can't really see why the wall controller needs a thermostat built in it? The TRV's tell it when boiler needs to run.

Without the link to TRV's the problem is when a TRV schedule causes it to open, the radiator will not get hot unless the boiler is running, so the TRV opens wider and wider until fully open, then the boiler starts, the radiators quickly heats up as valve fully open, and by the time it has closed, the radiator is stinking hot, and the room temperature over shoots.

So we need to set the lock shield valve to reduce the speed that the radiators heats up. Better when linked, but the linked TRV heads are expensive, so one selects key rooms for linked TRV's and use non linked much cheaper electronic heads for other rooms.

The Wiser instructions are hardly going to tell one you can get these EQ-3 Bluetooth Smart Radiator Thermostat.jpgcheap heads for other rooms, I paid £15 each in 2019. So if my family all go to bed at 10:30 pm if we have a wiser head in the slowest bedroom to heat, we can have cheap ones in rest of bedrooms.

I tried to set up late mothers house, TRV-report3.jpg it had target and current, so if current exceeds target then close the lock shield a tad, and soon I got rooms spot on. These did not link.
 
OK I’m all wired up. Thanks Ian!
Only thing I’m a bit confused on now is the room with both the smart thermostat and smart TRV in. Do I add both of these devices individually in the app or do they need to be linked in some way to work?
And when I’m setting a schedule or doing a boost via the app for that room should I do that on the TRV device rather than the thermostat device in the app?
Thanks again! Nearly there!
 
There's not much point having the stat in a room with a smart trv and not linking them- if they're both active they'll fight (eg TRV set to 20° at 8pm, stat set to 18° at 8pm. Stat is satisfied first, trv is still calling for heat so room temp will continue to rise til TRV is satisfied).
Having room stat in a room paired with trv is handy for fine tuning but if you only have the one I'd put it in the hallway.
 
joboro said:
OK I’m all wired up. Thanks Ian!
Only thing I’m a bit confused on now is the room with both the smart thermostat and smart TRV in. Do I add both of these devices individually in the app or do they need to be linked in some way to work?
And when I’m setting a schedule or doing a boost via the app for that room should I do that on the TRV device rather than the thermostat device in the app?
Thanks again! Nearly there!
Click to expand...
In the Wiser app you create a "room", but it is really just the name for a managed area which can be multiple physical rooms you wish to control as one. Below I'll call this an area to differentiate from the physical room, although in the Wiser app it's called a room. Confusing - you bet.

Let's assume you have a lounge and dining room you want to manage together. For simplicity if we call this "Family Room" in Wiser, this is just an arbitrary name. You could equally call it Fred or XYZ. That said, it's best to use something sensible. You could name the areas as "Kitchen", "Bedroom1", "Bedroom2", "Master Bedroom", "Charlotte's Room", etc.

You then add any device to the named area in the app. In your case you say that both the roomstat and TRV are in "Family Room". That associates them together. As you have six temperature sensing devices, that allow you up to six managed areas in the Wiser app. You can, of course, add more than one device to a named area.

As for the schedule or boost that's against the area. Likewise if you boost from the roomstat itself by pressing the +/- buttons that's boosting the area. Not sure what happens if you twist the TRV (boost) if the area contains both a roomstat & TRV.

So you should initially define your areas (rooms) in the Wiser app. If you had a 3 channel hub, the next stage would be to associate the room to a heating channel (1 or 3) but as you only have a single channel model all rooms are associated to "Channel-1"

Next add the devices and connect to the area ("room") you defined above.

Then define your schedules and associate each to an area ("room"). The same schedule can be used by multiple areas, but generally it should be 1-to-1.
 
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oldbutnotdead said:
There's not much point having the stat in a room with a smart trv and not linking them- if they're both active they'll fight (eg TRV set to 20° at 8pm, stat set to 18° at 8pm. Stat is satisfied first, trv is still calling for heat so room temp will continue to rise til TRV is satisfied).
Having room stat in a room paired with trv is handy for fine tuning but if you only have the one I'd put it in the hallway.
Click to expand...
Nope, the roomstat is king. It is the sole source of the temperature value used. Any TRV's in the same "room" are effectively managed by the roomstat. They are automatically linked as they are in the same named room.
 
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ian1182 said:
Nope, the roomstat is king. It is the sole source of the temperature value used. Any TRV's in the same "room" are effectively managed by the roomstat. They are automatically linked as they are in the same named room.
Click to expand...
Only if you link them (in the app) to be in the same Room. Just physically placing the room stat in a location with smart trvs doesn't automatically do anything.
 
oldbutnotdead said:
Only if you link them (in the app) to be in the same Room. Just physically placing the room stat in a location with smart trvs doesn't automatically do anything.
Click to expand...
Agreed. It might just be the terminology I used, by "same named room" meant the name defined in the Wiser app. The physical location is neither here nor there as Wiser has no knowledge of that.

If only the Wiser app used a different term to describe the grouping of physical rooms into logical areas. Calling it a room makes it more complicated than it should. It's unlikely you will have as many named "rooms" in the wiser app as physical rooms in your property.
 
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ericmark said:
Never a truer word. However how smart? The Wiser wall thermostat is really a hub, it accepts commands for heat and adjusts boiler output to suit, or if not OpenTherm then turns boiler on/off.

So I suppose it would go on a wall near the boiler so if it gets too cold and there is a risk of freezing boiler turns on? But can't really see why the wall controller needs a thermostat built in it? The TRV's tell it when boiler needs to run.

Without the link to TRV's the problem is when a TRV schedule causes it to open, the radiator will not get hot unless the boiler is running, so the TRV opens wider and wider until fully open, then the boiler starts, the radiators quickly heats up as valve fully open, and by the time it has closed, the radiator is stinking hot, and the room temperature over shoots.

So we need to set the lock shield valve to reduce the speed that the radiators heats up. Better when linked, but the linked TRV heads are expensive, so one selects key rooms for linked TRV's and use non linked much cheaper electronic heads for other rooms.

The Wiser instructions are hardly going to tell one you can get these View attachment 294749cheap heads for other rooms, I paid £15 each in 2019. So if my family all go to bed at 10:30 pm if we have a wiser head in the slowest bedroom to heat, we can have cheap ones in rest of bedrooms.

I tried to set up late mothers house, View attachment 294752 it had target and current, so if current exceeds target then close the lock shield a tad, and soon I got rooms spot on. These did not link.
Click to expand...
You're not understanding how the Wiser system works. The wall thermostat is NOT the hub, the hub is a seperate device which makes the connection to the boiler and the wall thermostat and iTRV's communicate with the hub. Any wall thermostat and/or iTRV can request the hub to turn the boiler on and off. The iTRV opens a variable amount dependant on the detected room temperature and will/should close slowly as the setpoint temperature is reached hence minimising any overshoot. You can not use a mix of Wiser iTRV's and other manufacturers iTRV's as the non Wiser iTRV can not ask the Wiser hub o turn on the boiler.
 
oldbutnotdead said:
Only if you link them (in the app) to be in the same Room. Just physically placing the room stat in a location with smart trvs doesn't automatically do anything.
Click to expand...
You have to actually configure the room stat to a room (or zone/area however the homeowner wants it setup), if you don't it is marked as "unallocated" and does nothing.
 
Thanks again for the advice. I’m all up and running with your suggestions and advice. Very happy. Thanks for sharing all your knowledge!
 
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