Starting out with central heating / radiator control
Posted: Tue Oct 18, 2011 1:03 pm
Hi folks,
I'm brand new to this board and to domotica in general and looking around to create a control system for my central heating system. In particular, I'm interested in creating multiple (probably 2 or 3) zones. I work from my home office on the first floor, so the single thermostat on the ground floor we have now is not sufficient.
I've read up on this forum and other places a bit, and it seems that FHT, Max! and (Danfoss) Z-Wave are the most commonly used systems for heating control. I do have some questions, hopefully someone can provide some insights here.
Using the Max! system, there is no direct control over the heating boiler, it only controls the radiator valves. However, as far as I understand, leaving the boiler on 24/7 will not help to save energy (probably use more energy than my current single-thermostat setup?). Is this understanding correct? If so, how would you recommend to interface with my boiler to turn on only when there is heat demand? I can imagine a small software solution here: Have a PC talk to the Max! Cube to find out if there is heat demand and then toggle a simple relais to turn the boiler on. However, doesn't such a software solution prevent the system from working autonomously at all, when the PC / software is broken for whatever reason?
Using the FHT system, I've found the FHT8W relais, which switches on the boiler when any thermostat signals a heat demand. However, this device seems very big and expensive (€90) for just a remote controllable relais (especially since it only needs to short a 24V signal for my boiler, I think). Are there extra hidden features here? Also, it seems that using the FHT8W will degrade to on/off switching of the boiler instead of modulating (though the modulation protocol of my Nefit Ecomline seems to be unknown as of yet, so I might need to fall back to on/off anyway).
Looking at pricing, the Max! system seems interesting. It is also easy to hack on, because of the (cheap) ethernet-enabled cube. The FHT system is slightly more expensive, but does seem more mature. However, it seems that the (only) radiator valve actuator they have (FHT-8V) does not have a manual override knob, it can only be remote controlled. Is that correct?
So far, some of my questions and thoughts. I welcome both answers and other ideas!
I'm brand new to this board and to domotica in general and looking around to create a control system for my central heating system. In particular, I'm interested in creating multiple (probably 2 or 3) zones. I work from my home office on the first floor, so the single thermostat on the ground floor we have now is not sufficient.
I've read up on this forum and other places a bit, and it seems that FHT, Max! and (Danfoss) Z-Wave are the most commonly used systems for heating control. I do have some questions, hopefully someone can provide some insights here.
Using the Max! system, there is no direct control over the heating boiler, it only controls the radiator valves. However, as far as I understand, leaving the boiler on 24/7 will not help to save energy (probably use more energy than my current single-thermostat setup?). Is this understanding correct? If so, how would you recommend to interface with my boiler to turn on only when there is heat demand? I can imagine a small software solution here: Have a PC talk to the Max! Cube to find out if there is heat demand and then toggle a simple relais to turn the boiler on. However, doesn't such a software solution prevent the system from working autonomously at all, when the PC / software is broken for whatever reason?
Using the FHT system, I've found the FHT8W relais, which switches on the boiler when any thermostat signals a heat demand. However, this device seems very big and expensive (€90) for just a remote controllable relais (especially since it only needs to short a 24V signal for my boiler, I think). Are there extra hidden features here? Also, it seems that using the FHT8W will degrade to on/off switching of the boiler instead of modulating (though the modulation protocol of my Nefit Ecomline seems to be unknown as of yet, so I might need to fall back to on/off anyway).
Looking at pricing, the Max! system seems interesting. It is also easy to hack on, because of the (cheap) ethernet-enabled cube. The FHT system is slightly more expensive, but does seem more mature. However, it seems that the (only) radiator valve actuator they have (FHT-8V) does not have a manual override knob, it can only be remote controlled. Is that correct?
So far, some of my questions and thoughts. I welcome both answers and other ideas!