Evohome firmware 02.00.19.31 Beta Trial - Exclusive for Automated Home Members

[SteveP]

Do the zones in question have remote sensors or just rely on the HR92's sensor ?

Generally a remote sensor will give better weather independent comfort year round with fixed set points - although it can take a little trial and error to find the best location in the room for the remote sensor to go to give subjectively equal comfort under different conditions.

I’ve been using evohome since it’s inception so have mainly HR80s but yes they predominantly use the inbuilt sensor. Just 3 rooms use the remote wall sensors DT90s. So maybe just due to old type thermostats perhaps?
Do agree with another post that perhaps a variable difference may be an idea as can allow individual homes to fine tune, unless there is a way to get the true “feels like”temp?
As also stated “an improvement” but already feeling like my initial enthusiasm is waning with the reality
Also switched off the adaptive load scaling as similar to another post I was getting a little weary from the pump never stopping as I don’t have a variable pump speed pump and so can get a bit noisy in the pipes when maybe only a few rads asking for heat.
Wondering if my real needs are
A) adjustable eco set
B) ability to have a spring/autumn schedule and a winter schedule. I can then use my in built Human sensors to adjust accordingly !

[mtmcgavock]

Also switched off the adaptive load scaling as similar to another post I was getting a little weary from the pump never stopping as I don’t have a variable pump speed pump and so can get a bit noisy in the pipes when maybe only a few rads asking for heat.

To reiterate that, my pump overrun hasn't stopped running all day nearly due to the short runs of a few minutes which kicks in the 5 minute overrun. Giving the learning the benefit of the doubt at the minute, but if it carries on like this after a week or so I too will be turning the Adaptive Load off.

[frankmalia]

I have seen random changes to 30 degrees on the old firmware on my system, although not recently. I even documented it on a thread here.

Try rebooting both the HR92's in the affected zones and the controller to see if it helps.

I'll let Andy the minion have look first remotely.. Then try that, as pretty sure not seen this before, and seen it 3 times in a day now. Plus I log my temps and SP, so would of seen this. I have seen a 30'C temp in hallway once, but I think sure this was override symbol, and you mentioned the reboot, which I probably did then.

At the moment it is not effecting anything as it switches back to SP once start optimisation has finished.

[DBMandrake]

To reiterate that, my pump overrun hasn't stopped running all day nearly due to the short runs of a few minutes which kicks in the 5 minute overrun. Giving the learning the benefit of the doubt at the minute, but if it carries on like this after a week or so I too will be turning the Adaptive Load off.

Not sure how this would be any different to opentherm which would tend to keep the pump running with very little boiler output ?

I actually have a 12 minute overrun on my pump precisely so it doesn't stop and start during every TPI cycle so I don't see this behaviour as a problem for me...

[mtmcgavock]

Not sure how this would be any different to opentherm which would tend to keep the pump running with very little boiler output ?

I actually have a 12 minute overrun on my pump precisely so it doesn't stop and start during every TPI cycle so I don't see this behaviour as a problem for me...

My point being that i've not seen any improvement levels in terms of comfort to warrant the extra cost of running/wear on the pump to be running all day at this current time, admittedly that may improve over the course of the week as the system learns. It seems to bring it on for a couple of minutes, say 5 times every 30 minutes which I guess it's supposed to do, just not seeing any benefit at this current time - if anything it'll cost more to run as it stands. As I said i'm probably not giving it long enough to learn.

[bruce_miranda]

In any case, I think a 5 min overrun is too little. Maybe keeping it as high as 30 like me, is unnecessary too. But with OT the pump rarely switches off in any case.

[Andy the Minion]

I didn’t get a boiler option when I registered - does it depend upon whether you use total connect or Honeywell home?

Steve, The others are commenting on the process of adding the service company for diagnostics, rather than requesting the firmware. The second is completely optional.

[DBMandrake]

In any case, I think a 5 min overrun is too little. Maybe keeping it as high as 30 like me, is unnecessary too. But with OT the pump rarely switches off in any case.

Which was the point I made earlier - OT systems already have the pump running near continously on light loads.

Although the pump running continuously across each TPI cycle (so long as there is some demand) might use slightly more electricity, it causes less stress on the pump and heat exchanger in the boiler to keep that pump running across each cycle than stopping and starting the pump during every 10 minute TPI cycle. Which is why I chose 12 minutes overrun for a 10 minute TPI cycle.

And on an old vented system like mine that constant stopping and starting of the pump can trigger kettling in the boiler due to the frequent sudden changes in flow and pressure.

[mtmcgavock]

Which was the point I made earlier - OT systems already have the pump running near continously on light loads.

Although the pump running continuously across each TPI cycle (so long as there is some demand) might use slightly more electricity, it causes less stress on the pump and heat exchanger in the boiler to keep that pump running across each cycle than stopping and starting the pump during every 10 minute TPI cycle. Which is why I chose 12 minutes overrun for a 10 minute TPI cycle.

And on an old vented system like mine that constant stopping and starting of the pump can trigger kettling in the boiler due to the frequent sudden changes in flow and pressure.

Yes but with OT theres a demand, so the pump is pumping somewhere - on a TPI cycle the BDR91 unlatches and closes the Heating MV and therefore it's just pumping round the bypass. So all the useable heat is just going round the bypass circuit.

[Andy the Minion]

Not sure how this would be any different to opentherm which would tend to keep the pump running with very little boiler output ?

I actually have a 12 minute overrun on my pump precisely so it doesn't stop and start during every TPI cycle so I don't see this behaviour as a problem for me...

In a previous life I came from the boiler industry and have been used to setting the pump to run constantly in opentherm or otc systems. The HR92 stay open when the boiler is off and my logic is this allows the heat that may have be left standing in a pipe run to be distributed evenly within the house and the water comes down to a nice steady return temperature ready for the next burner on cycle. I have no actual evidence which is better mind, just a gut feeling.