TPOne Calling for heat all the time.

[diyknowhow]

TPOne calling for heat all the time

I have a Baxi Asuure Heat 19 boiler.

A water cylinder with a small expansion tank next to it in a cupboard, I believe it is referred to as a closed system. All a couple of years old.

Problem is the controller Danfoss TPOne keeps calling for heating repeatedly for seconds and then stops, maybe boiler runs for 15-20 seconds then stops , 2 mins later same thing again.

As soon as the temperature drops even slightly on the display it calls for heating, lost count how many times. I was flicking through the Danfoss TPOne controller, under "Control Type" it is set to "Chrono 6", the other options are "On/Off", "Chrono 3" and "Chrono 12".

Could somebody please explain (dummies guide please ) the difference and whether changing the setting to something other than "Chrono 6" may prevent these countless repeated short cycles. I can't believe it's good for the boiler to fire up so many times. Thank you in advance.

 

[trojanhawrs]

Try the on/off, thats what normal thermostats do. Think the chrono thing is some kind of attempt at modulation but as you say, probably won't be great for the boiler, you'd really want a proprietary controller if you were looking for efficiency gains.

 

[diyknowhow]

Try the on/off, thats what normal thermostats do. Think the chrono thing is some kind of attempt at modulation but as you say, probably won't be great for the boiler, you'd really want a proprietary controller if you were looking for efficiency gains.

Thanks

There is a danfoss room sensor TS2A installed also.

Just changing it from "Chrono 6" to "on/off" shouldn't cause any damage to anything. By that I mean the physical setup of the pipes, cylinders, boiler etc can't be damaged by changing it to "on/off" on the TPOne. The installation is unaffected the control mode on the TPOne?

I have a TPOne downstairs and upstairs so will do the same for both?

Finally if i change it to "on/off" does it just mean that the TPOne will be slower to react to a slight temperature drop and therefore result in fewer cycles. So if Chrono 6 would cycle if the temp dropped from 21 to 20.5. The on/off setting may wait till 21 drops to 19.5 as an example?

 

[trojanhawrs]

I don't know exactly how it works to be frank, it won't damage your system though, worth a try to see if it makes a difference. The fact you have multiple thermostats makes me think you have zone valves though, there may be an overall controller that these are feeding into.