Honeywell Underfloor heating controllers

[Hoof Hearted]

Hi there, I'm considering having my heating system controlled by Honeywell Evohome. I have a question about the underfloor heating controller....

I have a single zone water underfloor heating in the kitchen. The controller is currently a Wunda. I've never been all that happy with it because it is just a thermostat. The floor takes 3 hours of heating before it gives out any heat, then it keeps giving out heat for 3 hours after the zone valve shuts off. Undershoot and overshoot. What I would like is a controller that switches the zone valve in anticipation of the temperature being reached. Such a device is known as a PID controller. Can anyone tell me if the Honeywell HCC80r is such a device? I downloaded the manual. It makes no mention of this.

 

[Basher]

I have UFH in our current property, but controlled by a Heatmiser system, and with that the 'pre heat'/ PID algorithm is in each of the NeoAir v2 room stats, not in the receiver/control box that activates the manifold valves.
In a previous property I did have Honeywell Evohome on a traditional radiator system, and with that the clever stuff was all in the wall mounted controller ATF800 unit. I would have thought PID, if it's present (which I would expect it to be) would be in there, not in the HCC80R, which by the way appears to be obsolete - superseded by HCC100.
Sorry - this may not help much, but it's somewhere else to look!

 

[Hoof Hearted]

I have UFH in our current property, but controlled by a Heatmiser system, and with that the 'pre heat'/ PID algorithm is in each of the NeoAir v2 room stats, not in the receiver/control box that activates the manifold valves.
In a previous property I did have Honeywell Evohome on a traditional radiator system, and with that the clever stuff was all in the wall mounted controller ATF800 unit. I would have thought PID, if it's present (which I would expect it to be) would be in there, not in the HCC80R, which by the way appears to be obsolete - superseded by HCC100.
Sorry - this may not help much, but it's somewhere else to look!

Thanks for the reply. I took a look at the HCC100. The description says that it has a "patented self-learning (fuzzy logic) algorithm for accurate zone temperature control". Maybe that's their way of describing PID. So I guess i'll go with it and start the ball rolling. Thanks for your help.

Ian

 

[Basher]

Thanks for the reply. I took a look at the HCC100. The description says that it has a "patented self-learning (fuzzy logic) algorithm for accurate zone temperature control". Maybe that's their way of describing PID. So I guess i'll go with it and start the ball rolling. Thanks for your help.

Ian

I remembered after I posted that our Evohome controller did allow you to select a setting (by room) so that it would reach the target temperature by the time you set. I.e. The heating would come on early so that by 7.00am (or whatever you set) it was the desired temperature. It did this by switching on earlier and earlier until the desired condition was met, and then remembered and used the empirical result.
This might be the 'fuzzy logic'. Seemed to work for our rads. But I suspect it's not strictly PID, and you may suffer 'overshoot' that PID would deal with, but the fuzzy logic will ignore, as the temperature is reached by the allotted time, but it will ignore the fact that an hour later the room is 2 degrees too hot!

But best wishes for your investigations!

 

[EvilDrPorkChop]

Sounds like you're running your underfloor heating wrong......is it in a slab?

Evohome is great though. Although I just use BDR91s and stats to control it using TPI. Works well, never had any issues or complaints.