I'm suffering with this too and could do with a new beta/update coming through. Actually struggling more with this after turning the heating off as we manually boost zones.Quote:
Originally Posted by DBMandrake
I'm suffering with this too and could do with a new beta/update coming through. Actually struggling more with this after turning the heating off as we manually boost zones.Quote:
Originally Posted by DBMandrake
Same here - with the hot weather we've been using a Custom action configured to 5C (discussed in another thread) to keep the heating off but still overrideable for towel drying etc, so whenever any radiator is on it is due to a manual override, hence no hot water reheat..Quote:
Originally Posted by mtmcgavock
Unfortunately had to switch off cold weather boost last night. Setpoint was 20.5 and boosting. Controller outside temp was 14'C, looking at weather reports the lowest temperature yesterday was 13'C, so should not be boosting. This fixed -10'C setpoint from a in accurate outside temp does not work. The offset needs to be variable and the outside temperature input needs fixing.
I had to switch off advanced load scaling a couple of days ago.
It had got a little bit cool in the evening so wanted to warm the bathroom up a little. 20 minutes later the boiler still hadn't fired up and I was being hassled about why the radiator was still cold.
The demand was showing 100% for the bathroom and 18% for the boiler.
Switching off advanced load scaling set boiler to 100% and allowed the radiator to heat up.
Maybe there should be some sort of temporary override to get around the odd occurrence of wanting to heat up a single room at this time of the year.
Can you not just increase setpoint to get it to kick manually. I think the load scaling seams to work quite well, less overshoots early on in the year when heating was on all the time. Was it not a combination of load scaling and warm weather shut down. Because the warm weather shutdown has to drop below setpoint about 1'C to allow zone to heat up.
Same problem here with my bathroom radiator and I raised this issue with Andy further up thread...Quote:
Originally Posted by Stevedh
I had to drop down load scaling from full to partial because I was completely unable to get the bathroom radiator to turn the boiler on if it was the only active zone. (100% heat demand from the zone, 5% heat demand to the boiler - less than the minimum 11% threshold before the boiler will fire!)
Partial load scaling helped quite a bit as it reduced the amount of scaling (but still gave enough scaling to minimise overshoots - the main purpose of load scaling) however I still sometimes struggle to get any heat from my bathroom radiator if it is the only active zone. Typically it will only generate about 20% heat demand to the boiler for 100% from the zone.
This will eventually heat up the radiator but it takes about half an hour, and doesn't get fully hot, versus the "towels nice and hot in a few minutes" that I would like to see. Like you I have had to explain to my other half why the radiator she turned on 20 minutes ago is still cold, and have had to manually turn off load scaling to work around it in a couple of occasions.
As I mentioned to Andy further up the thread the load scaling needs some kind of limit to how far it will scale the heat demand. Scaling a 100% heat demand down to 5% when it takes a minimum of 11% to even fire the boiler at all is just rediculous.
I don't care what the underlying rationale or logic is, any non technical user who turns up their bathroom to 25C with an ambient reported temperature of 20C and 30 minutes later still has a cold radiator and boiler not firing is going to think their system is malfunctioning. End of story.
Load scaling is a good idea but the heuristically learnt scaling factor needs to have a limit of about 4 to 1, eg 100% demand scaled down no lower than 25%, otherwise I think I will ultimately have to disable it. Minimising overshoots is not worth having radiators simply fail to heat up when they should.
No, increasing the set point doesn't help when load scaling is over eager. You can set the temperature to 30C and the radiator still won't heat up as the scaled heat demand can be <11%. Definitely a flawed implementation of a good idea.Quote:
Originally Posted by frankmalia
For once I am happy I have OT and dodged this Load Scaling bullet. It would have driven me nuts because I work from home and most days have only a single radiator on in the study, which happens to also be the coldest room in the house.
I've just turned off advanced load scaling, couldn't get any heat from the kitchen radiator and the weather here is terrible.
Set mine to partial the other day from full, same issue.
Mine has been on partial for a few weeks now too. It certainly helps a lot, (vs full) however I'm still sometimes unable to get heat from a single zone (usually the bathroom) when other zones have no heat demand.Quote:
Originally Posted by frankmalia
It's also very unpredictable and doesn't seem to correlate with the outdoor weather report. Sometimes the bathroom radiator works normal(ish) other times it can be turned up high for 30 minutes without the boiler even firing once as the heat demand is being scaled down below 11% and is thus insufficient to exceed the minimum on time for the boiler relay.
I still keep it enabled though (on partial) because it does a really good job of avoiding overshoots and regulating zone temperatures more smoothly. Hopefully Honeywell can tweak the algorithm to avoid the "no heat" scenarios the testers here are reporting but without losing the advantages it offers.