Ideal boiler cycling with Nest & Opentherm

[speedyuk]

I'm really grateful of the support. Here is the full details of the current rads. The lounge as you can probably guess is where the two Double Plus (or K2 I believe) are. I presume you would have to upgrade all the radiators to keep the system design balanced? So this would mean larger physical radiators in the lounge? I guess I should have done my research better regarding the minimum output rate of the boiler, I went with the Ideal ones as they were a heat only boiler that did support DHWP with Opentherm. Not sure other / better choice there was given the system as is? I guess I should just be greatful that I'm in a well insulated house that doesn't need much energy to keep warm.

 

[John.g]

There must be someway of limiting the minimum flow temperature surely to say 48/50ish to get the boiler away?, also maybe ask Ideal if there is some method of extending the anticycle time, if required.
What is the flow temperature on DHWP and does the boiler cycle when the cylinder temperature nears its SP of 60C?.

 

[speedyuk]

Hi John, yes I think you are spot on, if the minimum set flow temperature was around 50 degrees the boiler wouldn't overshoot. The room temperature would just be reached a bit sooner and the boiler would just be told to turn off in my case for probably around 30mins. This would be far preferable to the short cycling and longer time to get to room temperature. I've pinged an email off to Rishi Chandra to request the option. Will be interesting to see if I get a reply. The NEST Gen 3 is an old product now and I suspect the dev team have long since moved on to something else. I have been researching Opentherm gateways to act an intelligent middleman but I'd really rather not have some Heath Robinson contraption in the system.