Honeywell evohome and OpenTherm integration

[bruce_miranda]

Infact go lower and only raise it, if you feel the zoned rooms aren't heating up fast enough. I heat my house based on live usage patterns but if you do that based intended patterns, you will notice that at any time only a couple of rooms are really being heated up, the rest are either waiting to be heated, or just being topped up.

[G4RHL]

Infact go lower and only raise it, if you feel the zoned rooms aren't heating up fast enough. I heat my house based on live usage patterns but if you do that based intended patterns, you will notice that at any time only a couple of rooms are really being heated up, the rest are either waiting to be heated, or just being topped up.

I connected the OpenTherm Bridge this afternoon in place of the BDR91. I suppose the system goes into learning mode over the next few days or weeks. However, the boiler, an Intergas Xclusive 36kW, now shows something it has not before. The new boiler was installed last week. At present I have set the flow temperature to 70c but will in time reduce that. However, when I now look at the panel it shows a temperature reading of say 35c at times the boiler is not firing. Is this OpenTherm working and showing me the return temperature?

[SteveFraser]

I connected the OpenTherm Bridge this afternoon in place of the BDR91. I suppose the system goes into learning mode over the next few days or weeks. However, the boiler, an Intergas Xclusive 36kW, now shows something it has not before. The new boiler was installed last week. At present I have set the flow temperature to 70c but will in time reduce that. However, when I now look at the panel it shows a temperature reading of say 35c at times the boiler is not firing. Is this OpenTherm working and showing me the return temperature?

Even better. I believe it’s the flow temperature.
This can be adjusted on the Intergas X series boilers. I think the lowest temperature default is 30 C.

[kevinsmart]

I think it’s displaying the flow temperature request (control setpoint).

So if your current flow temperature exceeds this temperature, the boiler remains off but may continue to pump/overrun for a while.

[guyank]

When my flow temperature is within the tolerance and no additional heat is needed it displays 40C and number 1 as the pump is running but the burner is off. Once the heat demand is satisfied, I.e. the requested flow temp is below 40C, the both displays turn off.

[G4RHL]

When my flow temperature is within the tolerance and no additional heat is needed it displays 40C and number 1 as the pump is running but the burner is off. Once the heat demand is satisfied, I.e. the requested flow temp is below 40C, the both displays turn off.

Now a few days in with OT, yes I see this is what is happening. I am finding with OT that rooms get to their designated temperature a little slower than they used to but not such as to be an issue. More importantly as an experiment for a few days or so I have set downstairs rooms all to come on at 07:00 at 19C. They all reached that temperature more or less at the same time. One room was a little behind but not much. It is north facing with two outside walls one of which is exposed more than others. Often radiators seem cooler but the temperature is where is should be, the system being happy with what it has attained and/or been directed to do. The problem now is convincing the lady of the manor that whilst the radiator may seem cooler to touch it does not mean the room is cooler! Looking at the thermostat readout does not seem to convince!

[Wobbin]

Now a few days in with OT, yes I see this is what is happening. I am finding with OT that rooms get to their designated temperature a little slower than they used to but not such as to be an issue. More importantly as an experiment for a few days or so I have set downstairs rooms all to come on at 07:00 at 19C. They all reached that temperature more or less at the same time. One room was a little behind but not much. It is north facing with two outside walls one of which is exposed more than others. Often radiators seem cooler but the temperature is where is should be, the system being happy with what it has attained and/or been directed to do. The problem now is convincing the lady of the manor that whilst the radiator may seem cooler to touch it does not mean the room is cooler! Looking at the thermostat readout does not seem to convince!

I have a lady of the Manor like that too. If the heating is on, all the radiators should be hot. Why aren't they all hot !!??? <sigh>

[G4RHL]

I have a lady of the Manor like that too. If the heating is on, all the radiators should be hot. Why aren't they all hot !!??? <sigh>

I also now get “Why is boiler always starting? I keep hearing a whoosh sound every few minutes. I thought these boilers were meant to be quiet?” To explain that the boiler was not firing up but she could hear the pump starting and stopping to balance the required heat seemed to fall on deaf ears!

[bruce_miranda]

Increase the pump over run time a bit and then you won't have the pump stopping and starting as much.
You gain a lot with OT but you do lose stuff like the load scaling.

[G4RHL]

Increase the pump over run time a bit and then you won't have the pump stopping and starting as much.
You gain a lot with OT but you do lose stuff like the load scaling.

Thanks. According to the manual I can adjust this between 0 to 15 minutes. I will go into action. I have no idea what it is set at at present, presumably a default setting .