Need a thermostat for a 4 zone radiant heating system

Hello - I am new to Vera and anxiously awaiting my Vera 3. I have been using insteon and through a discussion with a smarthome tech found out about Vera which lead me to cancel my order for ISY… ;D

Anyway I am looking into to manage my vacation rental house that has radiant heating. The house has 4 zones for heating with No AC or forced air systems at all - just boiler, pumps and values.

I think most of the z waver thermostats I have looked at seem overly complex for what I need - I simple need a thermostat where the temperature drops below some set point the send turns on. All of the thermostats that offer programming are nice for forced air systems but not necessary with a radiate floor system.

Are there any simple z wave thermostats available?

Other ideas?

Thanks Jason

[quote=“yoabear, post:1, topic:169761”]Are there any simple z wave thermostats available?

Other ideas?

Thanks Jason[/quote]

Hello and welcome, I’ve been going down the route of heating control for the last month or so and have made a few false starts!

I decided to use the Everspring temperature sensor rather than a thermostat and let Vera send the commands to turn the heating on or off which let me use different scenes at different times of day to set varied set points through the day.

It was a steeper learning curve than I expected but the good folks on the forum have been a big help.

The first problem was the Everspring not updating Vera often enough, Vera rounds it to the nearest degree C and the Everspring was saving it’s battery and failing to send every change in temperature, this led to far too big a swing.

Chris, a regular poster here, has put an “easy to use” interface for a wired temperature sensor using a “one wire server” which is working excellently with regular updates and 0.1C resolution.

The standard graphical “scenes” interface does not make it easy to control temperature but some easy to implement “Luup code” does make it easy to control. I can send you the code I used if you want to go this route.

I’m now getting good control over the heating here with different temperatures at different times of day and a good comfort level through the house so it can be done, just takes a bit of thinking about.

If you just want one temperature set and a choice of times it’s on or off it will take a few minutes to set up.

I use an Everspring appliance switch to activate the heating, most systems can take an external interface of some sort where the thermostat would normally connect. In my case it’s an air source heat pump which I have replaced the oil boiler with.

Enjoy the journey

Nick

Interesting. Thanks for the reply I will look into that option. I am not currently at the house I plan to install the system at but will be over the holidays. The house froze in Feb of this year causing 25 separate pipes to freeze resulting in over 100k in damage. This is an old adobe house in Santa Fe and broken pipes and adobe = mud and it was a huge mess. Thankfully I was properly insured. I am hoping that Vera can help me have a little more piece of mind - because the property manager is not.

Anyway if memory serves the heating system has 4 zones as well as provides hot water and each of them can work together or independently.

The house has 4 very basic thermostats (wired with cat6 for future upgrade) which all come into the boiler room. If the temperature drops below a threshold the valve opens for that zone turning on the boiler and pump to send hot water to it. Once the temperature goes above a threshold the thermostats closes the valve and the unit turns off.

Radiant heat is very efficient but it takes a long time to heat a room so let’s say the system drops to 50 degrees because it is not in use. If the guests are arriving on some date I would need to have the unit set to 72 at least 2 days in advance.

One thought I had was each zone could have a separate temperature sensor (wired not battery) and then I could set up something to monitor the temperature as well as control/monitor the switching of the values and maybe not even worry about the thermostats. I know how to do this with insteon but I am not sure with Vera.

The reason the property froze was a guest upon leaving turned down the thermostats to the lowest setting which is off although it doesn’t specifically say that on the thermostat. Upon returning several days later after an extremely unusually cold period the damage had been done.

I plan on setting up a lot of temperature / freeze alarms to help reduce the likelihood of this reoccurring.

Ouch!

If you have Cat 6 cables running to convenient places then it will be quite easy to run some temperature sensors, they are 2 wire devices and all connect to the same cable if you want.

http://forum.micasaverde.com/index.php/topic,8381.msg53377.html#msg53377

Is the plug in that Chris did with the Ethernet interface.

That will give you temperatures for as many locations in the house as you want and the ability to get Vera to react to them.

For scenes I use the timer set to somewhere between 5 mins and 30 mins to initiate a temperature check

The “commands tab” has a command to turn the appliance switch that activates the heating on

This Luup code pasted into the code window

local lul_temp = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSensor1”,“CurrentTemperature”, 45)
if (tonumber(lul_temp) >9.0) then return false
end

replacing the “45” with the device ID of your tenperature sensor and the “9.0” with your desired temperature in degrees C then turns my heating on

A corresponding scene turns the heating off again.

You can add time bands as well but in your case you want to keep it on low to keep the frost out.

Very simple code and works much better like that than using the scenes graphical interface.

You can set up another scene at a lower temperature and get it to send you an e-mail if it’s getting too low (or a text message) so you can check it on the web interface and phone a local person if needed

Nick

Nick

Thanks again for your response.

Very interesting thread.

Question - When you say turning on and off the heat - what is doing that? The thermostat? I understand that Vera can send the signal but what is the switch that is recieving the signal?

In my case I have a Z wave appliance switch that is then operating a mains powered relay. That relay is connected to the thermostat connection point to my heat pump that is generating the heat and activates it.

I am in the electronics business so happy pottering around with relays and mains wiring etc. Depending how your heating ssytem is wired and what the thermostats do (activating zone valves probably) you may be able to simply apply mains from the appliance switch to the relevant terminals but you would need to trace out the wiring first or find drawings. It would be logical if the thermostat was activating the valve and the switch within the valve activating the boiler.

It depends what your background is how happy your are pottering with the wiring.

Nick