Smart Thermostat and Smart TRV installation advice

[joboro]

Hi all,

I've just bought a Drayton Multizone Smart Thermostat and 5 of their smart TRVs and looking for advice on the best way to set things up so had a few questions. Please let me know if you need to know anymore about the house and number of rooms to advise best. The boiler is a Main 30kw combi.

- Do I have to put a smart thermostat on all radiators or should I not bother on the hallway, and maybe the bathroom?
- If I do choose not to put a smart thermostat on all the radiators, would it be worth having a standard TRV on those ones or best with nothing?
- Is there a best room to put the smart thermostat in or should it go on the landing or something like that?

Not sure if it helps to know but the reason I'm getting this system is that at the moment we currently have a wired room thermostat in the kitchen which isn't a good place for it as the temperature fluctuates a lot depending on if we're cooking or not. We also have a newborn premature baby so want to be able to ensure quite specific temperatures in the room the baby is in ie. bedroom at night and various other rooms during the day.
Any other tips for install based on the above would be great!

Thanks,
Joe

 

[oldbutnotdead]

Apparently (and fairly obviously I suppose) the smart trvs don't like bathrooms so stick a standard one in there.
Smart trvs require a thinking change. On a conventional setup the room stat often ends up in the hallway. Hallway rad should also keep it's conventional valves, it's possible it is set up as a bypass heat sink.
Correct rad sizing (and now TRVs) mean when the hallway teaches set temp the rest of the house is probably there.
With your new smart valves each radiator can call for heat on its own so the central thermostat doesn't really work properly (it might be satisfied but unless you put all the smart trvs in one 'room' (in the app) the hallway will keep getting hot cos other rads are calling for heat).
So, your strategy;
For sure you want a smart valve in the kids room.
How many rooms and radiators do you have anyway?

 

[ian1182]

I assume you have purchased the single channel Wiser and have one roomstat together with your 5 smart TRVs. As you no longer have a fixed location for the roomstat (i.e. it's connected to the Hub via wireless) I would recommend you fit a TRV (smart or otherwise) to all radiators bar the bathroom. Then set the TRV in which ever room contains the roomstat to max. This gives you the flexibility to move the roomstat at your leisure.

As you have 6 smart stats (1 x roomstat + 5 x iTRV) that allows you up to six zones. You should probably place the roomstat in the room that heats slowest as that allow the non-Smart TRV's to do their business and slow/reduce flow prior to the boiler cutting out due to the roomstat temp being achieved. Any rooms with the smart TRV's will start the boiler on their own.

Questions I'd ask are such as
how many radiators
how many logical zones do you want. For example kitchen, lounge, bedrooms, etc
Is the house occuppied 24 x 7
do you not use certain rooms during the day (such as bedrooms). If so these are ideal candidates for a smart iTRV.

As a general observation, in the old days with dumb thermostats, you would often have heating on times and off times. With a smart heating system you move across to a permanently "on" situation but use the stats to vary the temperature across the day such as 21c daytime and 16c overnight or whatever your preferences are.

 

[Mister Banks]

Hi all,

I've just bought a Drayton Multizone Smart Thermostat and 5 of their smart TRVs and looking for advice on the best way to set things up so had a few questions. Please let me know if you need to know anymore about the house and number of rooms to advise best. The boiler is a Main 30kw combi.

- Do I have to put a smart thermostat on all radiators or should I not bother on the hallway, and maybe the bathroom?
- If I do choose not to put a smart thermostat on all the radiators, would it be worth having a standard TRV on those ones or best with nothing?
- Is there a best room to put the smart thermostat in or should it go on the landing or something like that?

Not sure if it helps to know but the reason I'm getting this system is that at the moment we currently have a wired room thermostat in the kitchen which isn't a good place for it as the temperature fluctuates a lot depending on if we're cooking or not. We also have a newborn premature baby so want to be able to ensure quite specific temperatures in the room the baby is in ie. bedroom at night and various other rooms during the day.
Any other tips for install based on the above would be great!

Thanks,
Joe

Definitely put the room thermostat and a smart TRV in the babies room. The TRV’s are not great at estimating room temperature if you need high accuracy. I have smart TRV’s on all radiators except in our three bathrooms and the utility room and I have a second room thermostat in our lounge which controls two smart TRV’s. Room thermostats are recommended in rooms where the TRV is partly concealed, where there is more than one TRV or where you need temperature accuracy.

 

[joboro]

Thanks for the speedy replies!
We have 3 bedroom radiators, 1 study, 1 kitchen/diner/, 1 living room, 2 x bathrooms (both towel rads), and 1 in the hallway. So in total 9 rads.
In terms of zones I think we'd probably want 3 or so zones. Maybe 4. The bedrooms could definitely be turned off during the day. And then at night rooms like the living room could be turned off.
The house is occupied pretty much 24/7 at the moment with my other half on maternity leave.
Would having the thermostat in the living room and no smart TRV in there make sense? Then the other 5 TRVs in the 3 bedrooms, nursery, kitchen/diner?
Bathrooms and hallway with no TRV but they would benefit from 'dumb' TRVs?

thanks,
Joe

 

[Mister Banks]

Thanks for the speedy replies!
We have 3 bedroom radiators, 1 study, 1 kitchen/diner/, 1 living room, 2 x bathrooms (both towel rads), and 1 in the hallway. So in total 9 rads.
In terms of zones I think we'd probably want 3 or so zones. Maybe 4. The bedrooms could definitely be turned off during the day. And then at night rooms like the living room could be turned off.
The house is occupied pretty much 24/7 at the moment with my other half on maternity leave.
Would having the thermostat in the living room and no smart TRV in there make sense? Then the other 5 TRVs in the 3 bedrooms, nursery, kitchen/diner?
Bathrooms and hallway with no TRV but they would benefit from 'dumb' TRVs?

thanks,
Joe

If you put the room stat in a room with no smart TRV it is controlling the heating in all the rooms without a smart TRV. The problem then is that when the room stat calls for heat it will heat up all manual TRV rooms but then when a smart TRV calls for heat it will also heat up all the manual TRV rooms. Personally I wouldnt use a room stat without a smart TRV unless you don't use any smart TRV's but then you are missing out on the control that a smart system provides.

 

[ian1182]

I have doubts that a kitchen is ideal for a smart TRV, there are too many external influences over the temperature such as the oven or hobs. You probably want to be able to control the kids room independent of others and that's good for a smart TRV. Likewise the study would be a suitable candidate depending on usage patterns. You don't want to turn the heating off in any room during the day or overnight but rather lower the scheduled setpoint temperature. If the room drops below your value then at least the heating will pop on to maintain the temp. Likewise even overnight in the lounge, study, etc you would not want the room temp not to drop too far. You have up six periods per day for each zone, so make good use of those to manage the expected temp across the day or night. For example in the lounge 8am to 10am 21c, 10am to 5pm 19c, 5pm to 10pm 21C and 10pm to 8am 16c.

Given that it's fairly easy to move the roomstat or smart TRV's between rooms it's probably best to do some experimentation to see what works for you

 

[joboro]

If you put the room stat in a room with no smart TRV it is controlling the heating in all the rooms without a smart TRV. The problem then is that when the room stat calls for heat it will heat up all manual TRV rooms but then when a smart TRV calls for heat it will also heat up all the manual TRV rooms. Personally I wouldnt use a room stat without a smart TRV unless you don't use any smart TRV's but then you are missing out on the control that a smart system provides.

I see. So if I had both the thermostat and a smart TRV in there would it react to the thermostat or the TRV?
What will happen to the areas that have a dumb TRV or no TRV if I did as you suggest? What would trigger them to cut off?

 

[joboro]

I have doubts that a kitchen is ideal for a smart TRV, there are too many external influences over the temperature such as the oven or hobs. You probably want to be able to control the kids room independent of others and that's good for a smart TRV. Likewise the study would be a suitable candidate depending on usage patterns. You don't want to turn the heating off in any room during the day or overnight but rather lower the scheduled setpoint temperature. If the room drops below your value then at least the heating will pop on to maintain the temp. Likewise even overnight in the lounge, study, etc you would not want the room temp not to drop too far. You have up six periods per day for each zone, so make good use of those to manage the expected temp across the day or night. For example in the lounge 8am to 10am 21c, 10am to 5pm 19c, 5pm to 10pm 21C and 10pm to 8am 16c.

Given that it's fairly easy to move the roomstat or smart TRV's between rooms it's probably best to do some experimentation to see what works for you

Only reason we'd like one in the kitchen is that it's really in the dinning room rather than kitchen but it's open plan and what happens at the moment is that we have that room getting quite cold when we aren't cooking and then very hot if we are cooking. Would a smart TRV not help to some extent with that?

 

[Mister Banks]

I see. So if I had both the thermostat and a smart TRV in there would it react to the thermostat or the TRV?
What will happen to the areas that have a dumb TRV or no TRV if I did as you suggest? What would trigger them to cut off?

Thats the problem with non TRV rooms, they will always heat up when a smart TRV calls for heat. Thats why I have my bathrooms with no TRV's on the radiators as I don't mind a cosy bathroom.

In a room with a room stat and smart TRV the room stat controls the temperature, thats why you need to position the room stat carefully.

 

[ian1182]

Only reason we'd like one in the kitchen is that it's really in the dinning room rather than kitchen but it's open plan and what happens at the moment is that we have that room getting quite cold when we aren't cooking and then very hot if we are cooking. Would a smart TRV not help to some extent with that?

Yes, a smart TRV would work in that situation.

One area that Wiser has an advantage is that local control does not depend on internet access just a working home wifi. On the back that there are several Home Assistant projects to monitor/control the Wiser system such as

Drayton Wiser Home Assistant Integration

Hey all, thought its about time I contributed to the HA community. Ive recently moved to the Drayton Wiser Heating platform (from the Max!Cube stuff) and Ive written a Home Assistant Component . Its probably best described as “beta” and available here...

community.home-assistant.io

I have 24 months of data at 5 minute intervals for each zone and can easily see how often the boiler fires up for heating or temperature variations over the day. I found that helpful in tuning the system alongside the Insight views available in the Wiser App.

 

[ian1182]

I see. So if I had both the thermostat and a smart TRV in there would it react to the thermostat or the TRV?
What will happen to the areas that have a dumb TRV or no TRV if I did as you suggest? What would trigger them to cut off?

If a radiator has a dumb TRV the only "control" is when it senses its local temp is meet and then closes. That will not trigger the boiler to stop of course. If the radiator has no TRV it will just keep heating until the boiler is triggered off by the room stat and all smart TRV's have also meet their setpoint temp.

Any zone with just dumb TRV's or no TRV's is at the mercy of the smart zones to start/stop the boiler. Hence any such rooms should have a dumb TRV fitted to limit how warm the room can get.

 

[joboro]

If a radiator has a dumb TRV the only "control" is when it senses its local temp is meet and then closes. That will not trigger the boiler to stop of course. If the radiator has no TRV it will just keep heating until the boiler is triggered off by the room stat and all smart TRV's have also meet their setpoint temp.

Any zone with just dumb TRV's or no TRV's is at the mercy of the smart zones to start/stop the boiler. Hence any such rooms should have a dumb TRV fitted to limit how warm the room can get.

OK thanks. Would you even include a dumb TRV on the bathroom rads?

 

[joboro]

Thats the problem with non TRV rooms, they will always heat up when a smart TRV calls for heat. Thats why I have my bathrooms with no TRV's on the radiators as I don't mind a cosy bathroom.

In a room with a room stat and smart TRV the room stat controls the temperature, thats why you need to position the room stat carefully.

Ahhh OK this makes sense I think. So if I put a smart TRV and smart stat in the baby room the room stat would tell the smart TRV to shut off at the right temp?

 

[joboro]

I'm very glad I asked you all for help! You're full of useful information!