A couple of V-Smart questions

Yes the evohome does a similar thing.

But

When the weather outside was 19 degrees, my indoor stat is set at 21 degrees.

Due to the warmth outside it felt a pleasant and comfortable temperature, we had the patio doors open to the kitchen as it was sunny. But the system wanted to call for heat still.

I had this on a couple of weekends and I had to keep manually switching the heating off.

Also in the mornings the temps drop and the house drops to around 19 degrees so in the morning the stat is calling for heat, but I don't want the heat as it's a nice comfortable temperature.

The only way round this was to either alter my timings or do the ifttt.

I'm not 100% sure how the v smart works, but I presume it is similar


Ah, well I'm talking about absolutes whereas you're more talking about 'perceived temperature', those are two different things. I'm happy for the V-Smart to take care of the former, to literally get the indoor temperature nailed down to what I've set it to be. There are indeed occasions when for no real reason I wish the temperature to be a degree warmer or cooler (it might even be my getting a little warm doing say the housework) and on those occasions I would literally just make a manual adjustment, up or down, and that's easily done on my phone. With the V-Smart as soon as you've done that it will keep that for the next six hours, but also immediately offer to reduce that on a sliding scale down to 1hr. That works just fine for me (y)
 
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I rang them a couple of times, concerned about what it was supposed to be doing with these brief runs. Only on my third call was I told it was the anti-seize system operating. There was absolutely no demand for any heat, yet very occasionally I would be in the kitchen, where the boiler is and hear it seem to go through it's purge before starting, then just stop. I was concerned there might be an issue on my new system, so spent time trying to work out what was going on.

(y)
 
Ah, well I'm talking about absolutes whereas you're more talking about 'perceived temperature', those are two different things. I'm happy for the V-Smart to take care of the former, to literally get the indoor temperature nailed down to what I've set it to be. There are indeed occasions when for no real reason I wish the temperature to be a degree warmer or cooler (it might even be my getting a little warm doing say the housework) and on those occasions I would literally just make a manual adjustment, up or down, and that's easily done on my phone. With the V-Smart as soon as you've done that it will keep that for the next six hours, but also immediately offer to reduce that on a sliding scale down to 1hr. That works just fine for me

There aren't many systems which can adjust for perceived temperature, because the 'perceived' depends on so many factors. My car does a pretty good job with its climate system, but that has a solar sensor detecting the IR heat from the sun.

What seems to work best for us, is setting the default daytime temperature to 18C, then just nudge that up if we find we need to.
 
I rang them a couple of times, concerned about what it was supposed to be doing with these brief runs. Only on my third call was I told it was the anti-seize system operating. There was absolutely no demand for any heat, yet very occasionally I would be in the kitchen, where the boiler is and hear it seem to go through it's purge before starting, then just stop. I was concerned there might be an issue on my new system, so spent time trying to work out what was going on.

V-Smart I assume is a bus control and generally the operation of the boiler mostly switches to the control from the boiler software with bus control rather than the boiler operating according to an ON/OFF thermostat. Some boiler software would remain unaltered with bus control and one of these features would be anti-stick; what that generally means is if something is not used within a 24hr period, the diverter valve or pump for example, the boiler will exercise it for a few moments to stop them sticking through long periods of idleness and to keep O rings used. The boiler shouldn't fire although the fan might start. Perhaps that's what you're hearing, did the boiler warm up?
 
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The boiler shouldn't fire although the fan might start. Perhaps that's what you're hearing, did the boiler warm up?

As said - from what I was noticing when I happened to be in the kitchen when it did it, at a guess it would go through the process maybe once per day, not set time and no it didn't produce any burn/heat. It sounded just as it always sounded when about to burn gas, it would run a 'purge cycle' on the fan, pump would run, then it will just shut down. It doesn't seem to matter whether or not it has previously been in use, it does it anyway.
 
It may be the warm start or hot water pre-heat you are hearing, or the pump proving test.

The Pump and Diverter Valve exercise is activated by the boiler software if NO other demand is received in a 23 hour period (highly unlikely if hot water is used).

What you are hearing is probably the pump proving test. Periodically the boiler will check the static system water pressure is above the minimum required, then run the pump and check for a rise in pressure to prove the pump is operational. At the same time both temperature sensors are checked. Pressing the i button or looking in system monitor in that case would show S.97 and S.98.

Warm start is where the boiler continues to run the pump after a hot tap is used to scavenge any latent heat from the heat exchanger, or periodically fires the boiler at minimum rate and run the pump to raise the boiler temperature. This runs to your set HW temperature to provide a ‘head start’ the next time hot water is used. This is switched on in the vSMART app with the tap symbol. The temperature is monitored by a sensor clipped onto the plate heat exchanger. The boiler works for hot water outside of these ‘tap symbol’ periods, just starting from cold with no pre-heat. Warm start is usually switched off overnight. In the heating season warmstart doesn’t fire much on its own as it uses heat from the central heating function.

In reality, don’t second guess or over think what the boiler and controls do. It all does it for a good reason (well, most of the time)

Hope that helps.
 
What you are hearing is probably the pump proving test. Periodically the boiler will check the static system water pressure is above the minimum required, then run the pump and check for a rise in pressure to prove the pump is operational. At the same time both temperature sensors are checked. Pressing the i button or looking in system monitor in that case would show S.97 and S.98.

Mine is an heat only and to help them find out what it was doing they asked me to check the display, when it did it. There were nothing showing errors, no demand and no faults recorded, each time I was quick enough to catch it doing it. Further - it would be most noticeable in the summer with no heating demand, but still a demand to bring the cylinder fully to temperature at least once per day - so it was ignoring the 23 hour rule.
 

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