what trv bodies do you have?
Old thread but i just want to send a quick update.
It appears the main reason why my rads were not getting hot was an issue with trvs.
It appears that when there were open at 20-30 they were not getting a flow. Im not sure if its a fault with valves or hr92 design issue but i have unscrewed all hr92 about 2mm. So when they are open at low flow the vavle is open probably in half which makes a flow much better.
I have also set them at full stroke but dont think it actually matters
what trv bodies do you have?
I work for Resideo, posts are personal and my own views.
20 to 30 what ? If you're talking about the valve pin position as reported by option 10 in the HR92 menu that is normal - the valve is not expected to start flowing until 30% pin position. This is taken into account by the design of the system which doesn't start calling for heat until an HR92 pin position is >30.
See the following graph I derived which shows the relationship between HR92 valve pin position and heat demand:
Heat demand here is reported in the system summary page of the Evotouch.
If you're having to unscrew your HR92 adaptor by 2mm then your valve bodies are not compatible with the HR92 - probably the pin is too long. You're never going to get completely satisfactory results with these valve bodies with the adaptor partly unscrewed.
Last edited by DBMandrake; 7th March 2020 at 08:36 PM.
Hello
I have the Evohome + 4 x HR92 + the Intergas Exclusive 24 boiler with the Nodo OpenTherm Gateway Monitor system (not sure how this works just yet ) will come back again in another post to explain.
My issue at the moment (if you please) is - I have connected an outside Temp sensor Intergas 203207 but seems not to influence the Evohome control, I believe it uses a Web based value normally - So how do I integrate this sensor into the boiler controls, will a boiler parameter have to be changed - also what NTC Resistance/Temp graph does the sensor conform too thanks in advance...joe
Unfortunately Evohome currently does not do anything with the OpenTherm read outside temperature. The displayed temperature and weather optimisation features are based on the Internet read temperature, which, depending on your location, may be inaccurate.
In this article I explain how you can implement flow temperature weather compensation using the Nodo gateway:
https://www.automatedhome.co.uk/tuto...l-evohome.html
The INTERGAS 203207 OUTSIDE SENSOR is NTC 12KOHM. I found the temperature reading to be quite accurate, very close to my weather station temperature.