Hello
it’s two weeks that I installed HASSOS on a raspberry pi 4, I added some temperature humidity sensors and now some TRV (sonoff trvzb) are on the way to my home.
I have a single level home with kitchen and living room that are well connected, two sleeping rooms and a bathroom.
Heating my home is mainly done by a wood stove in living room that produce a good amount of heat, so living room and kitchen are easily at 23/24°C during our stay at home.
The two bedrooms are colder and this cause mold growth, in the northern room in particular. This is because that room is 4/5 degrees less than the living room, so hot air goes to that room, carrying humidity that condense on the wall (I bought a VMC that must arrive soon).
Each room have its own TRV and a temperature/humidity sensor far from the radiator, bathroom radiator is always open, it has not a TRV.
The boiler is controlled by a Tuya wifi thermostat.
All sensor, thermostat and trv are integrated in HA.
So my idea is to warm cold rooms by mean of the gas boiler/radiator when kitchen and living room are well warmed.
So the trvs must be independent and I must activate the boiler warming based on the trv in the cold room that has its state on heating, while living room and kitchen must TRVs must be closed.
This during my presence at home with stove fired up, and during night or those days when I don’t fire my stove all should be controlled by boiler with schedules…
I was reading a lot and seeing many videos, so I see many approach to this problem but I’m a little confused on which could be the simplest to adopt.
Could you please point me to some easy solution (if there is) and to what should I learn to get to my target?
Thanks everybody
It’s basically very easy to do. You can zone it as you wish, every room signle zone, multiple room single zone… whatever.
install Better thermostat and Better thermostat ui from hacs. Set up your trv using this integration. It does support outside and room temperature sensors for trv calibration.
The only thing left to do is to set target temp on the rooms. You can set kitchen and living room to 21 and trv will close those valves or keep them partial closed all the time. This will create resistance in down stairs radiators and more heat will be sent to upper radiators. Set them to some unreachable temperature like 27 or more.
Word of caution. As I have fire place I know how fast and strong this can heat up water in radiators. Be sure to crank radiators to 27 or 30 or even more before you are burning some woods in it.
Thanks @ddaniel
I already installed BT and its UI with outside and separate calibration temperature/humidity sensor.
I see I can also group TRV (I have two in Living room and one in kitchen, and temperature in these rooms is very similar).
So I can set a common temperature for these two rooms and other temperatures for the two bedrooms.
I’m waiting for TRVs to arrive, I just bought one from Amazon to see if it was working ok with my setup, then other 6 from Sonoff store.
Then I can use the tuya thermostat to turn on the boiler heating, let’s say I can rise the desired temperature in it to turn on the gas boiler? or is it better to install a parallel dry switch? May be this last solution can be dangerous because TRVs must be opened if someone rise up the tuya thermostat…
Does BT has its own schedules? Or must I set them in Home Assistant in some way?
Anyway my fire place does not heat radiator water, it’s a common stove not a hydro one.
Radiators are heaten by a gas boiler
I have buderus furnace and it has its own programming schedule. I just fine tune it to provide desired heat in the house. Trvs doesn’t turn on or off heating. Everything is done automatically on the furnace depending on outside temperature and some other settings. I just turn on or off trvs by automation depending if furnace summer mode is in on or off status. It preserve trv batteries.
I’m using trvs just for zoning and it works great. I had the same problem as you, kitchen and living room are always much warmer than the bedrooms. Some rooms that are not used can have lower temperature and by zoning it will stick to that temp. With classic radiator valves this wasnt possible.
Although I have only 6 smart trv and have to buy much more i managed to archive the same thing you are trying. To provide more heat to the bedrooms.
I don’t use any schedules because it just drain trv battery and do basically nothing.
Ok, but how do you tell your “furnace” to turn on and produce hot water if its thermostat say it’s already warm (its thermostat is in the living room let’s say)?
You pump a given value, let’s say 30°, on the furnace thermostat when a TRV request heating? and then when it’s achieved the target temperature you restore the scheduled/previous value?
I have custom made pcb with esphome one it. It is sold for those furnaces by one guy so I can control my furnace remotely using esphome. It also provide a lot of sensor so I can tell what is going on and do a fine tuning over my comp.
Furnace is using outside thermostat to determine if the summer mode is on or off and weather it should heat or not. It has a lot of options for fine tune heating but most important one is referent temperature as this is providing heating curve. It does have some algorithms to calculate how much heating is needed using outside temperature and some other settings.
it does this very accurate as I set it on 21 degree and average temperature downstairs is something more than 20 degree and in bedrooms somewhere between 20 and 21 degree. I know that as I have a lot of temperature and humidity sensors around the house.
I use smart trvs just to regulate how much radiator is opened or closed. I don’t care about trv requesting heat because heat provider is furnace and it cannot be set up in the way that it will be turned on or off by trv requesting heat. For heat you have to fine tune furnace.
Edit:
And yes, heating water. It has a 190 liter tank for domestic water. I use automations to set hot water temperature. During the day hot water is on minimum and that is 30 degrees. I just crank it up in the morning and in the evening by automations when i need hot water. During the day no one using it so it could stay on minimum. And some other settings for hot water…
So you see, it’s not so simple… 
Anyway I will try to understand if the trick of rise up the tuya thermostat target temperature is viable or not.
I hope someone with a similar problem will share his solutions.
Hvala 
It is but it has a lot a variables. Its just seems complex but it isnt.