Evohome with Heatpump - Shortcycling Inefficiency due to limited boiler settings.

[ecoheated]

How are you extracting the data for the plots please? Are they direct from Evohome? I can chart zone temps and changes from idle to heating via InfluxDB in Smartthings. I would like to track Boiler on off as you've done.

Ta

Well, bad news, i did it all manually.

[Somebody]

Well, bad news, i did it all manually.

So spanning over an hour and half, you tracked the on off times of the boiler and the UFH pump, along with the noted boiler %ge, manually? if so, fair play to you!

[ecoheated]

So spanning over an hour and half, you tracked the on off times of the boiler and the UFH pump, along with the noted boiler %ge, manually? if so, fair play to you!

i did !

Luckly from my desk.

I can see the heat pump status live.
I can see the pump on the UFH from my desk with the cupboard door open!
And i have my Evohome next to me. With a stop watch and Excel open.

Not so bad.

[DanD]

Quick observation on the underfloor heating controllers.
When viewing the "System Summary" page in settings, you will never get the demand for each room when using the underfloor heating controllers.
Tonight i figured out that the total demand for all the rooms on the controller is displayed under the room set to output #1 on the UFH controller.
I also noted that the boiler demand is always equal to the highest demand shown from any of the UFH controllers.

Thanks for confirming this. I've been wrestling with the heat demand data produced by the HCC80R for a long time and despite not having underfloor heating myself, I'd like to add it as a supported device to the Evohome logging and control code which I support (Domoticz).

The Opentherm boiler control methodology sounds like it would be far more suited to your heat pump need (if your heat pump supports it). If it does, then replacing the BDR91 boiler control relay with the Opentherm Bridge (R8810) might give you the level of control you'd prefer. I just have a conventional gas boiler, but switched to the Opentherm set-up and its flow temperature modulation seems to work really well for me, but just from the perspective of room temperature control via conventional radiators.

Dan

[DBMandrake]

Madness. Yes, we're S plan.

We're S-Plan as well however I have 3x BDR91 - hot water and heating zone valve relays and a boiler relay, so I do get the cycle time adjustments. (As well as hot water overrun)

[paulockenden]

We're S-Plan as well however I have 3x BDR91 - hot water and heating zone valve relays and a boiler relay, so I do get the cycle time adjustments. (As well as hot water overrun)

That's why I mentioned traditional wiring!

having the extra BDR91 makes a lot of sense. And also protects you from broken microswitches in the zone valves, which seems to be a regular thing.

P.

[apkent]

Forgive my ignorance (and very simple mind) but I can't pictures how that is either wired or configured in the controller?

System devices > Boiler control > wireless relay?

[paulockenden]

Wired directly to the boiler (instead of using feeds via the zone valves). And configured as boiler control on the controller. Normally with S Plan there's no boiler control (lots of people mistakenly add it, causing all kinds of problems).