I've just moved into a place with a Danfoss TP5000 programmable thermostat and an Ideal combi. Everything works fine, but I can't figure out the behaviour when the target temp is reached. In order to maintain the temp, the programmer often calls for heat to the boiler for 30 seconds, before stopping calling for heat. Surely in such a small timeframe the raditors can't have provided sufficient heat to raise the room temp to the point of shutting off the thermostat.
How are these new (to me) stats meant to work? In my last house it was a mechanical stat with a separate drayton programmer. When the set temp was reached, the call for CH stopped, then at the point that the temp fell below the set limit and triggered the stat to call for heat, it would do the very same, taking maybe 20 mins or so for it to reach the desired temp again. I appreciate all houses are different and will suffer different losses and re-heat times, but this calling for CH for 30 secs at a time, multiple times per hour seems unusual. Its the programmable stat that's calling for heat rather than the boiler itself short cycling.
How are these new (to me) stats meant to work? In my last house it was a mechanical stat with a separate drayton programmer. When the set temp was reached, the call for CH stopped, then at the point that the temp fell below the set limit and triggered the stat to call for heat, it would do the very same, taking maybe 20 mins or so for it to reach the desired temp again. I appreciate all houses are different and will suffer different losses and re-heat times, but this calling for CH for 30 secs at a time, multiple times per hour seems unusual. Its the programmable stat that's calling for heat rather than the boiler itself short cycling.