Hi, I wonder if anyone can help solve a mystery. I've a Vaillant Ecotec Plus 430 boiler (installed as an unvented system) that's about 3 years old and apparently working well.
However, in recent months I've occasionally been woken by the boiler fan
suddenly starting up in middle of the night, just for 30 seconds or so, for no apparent reason. At least, I assume it's the fan; a quiet, high-pitched whine that first rises in pitch as it speeds up, then steady for a few seconds, then falls away as it slows to silent again.
At first I thought I must be dreaming it, but I've heard it often enough now to be certain it's real. The problem is that, by the time I'm awake enough to be aware, it's only a few seconds before it stops again and I can't get to the boiler in time to check the display.
My timeswitch is definitely NOT calling for heating or water in the small hours. I've never heard it twice in the same night and I reckon it's probably only occasional nights it does it.
I rang Vaillant's homeowner technical line and all they could suggest was that it might be something to do with the boiler entering "burner anti-cycling" mode, and to look for an egg-timer icon on the display. But they couldn't explain why a boiler that had last fired at least 6-8 hours previously would suddenly decide to enter this mode (nor why it would lead to the fan starting up briefly).
Anyone come across this before?
However, in recent months I've occasionally been woken by the boiler fan
suddenly starting up in middle of the night, just for 30 seconds or so, for no apparent reason. At least, I assume it's the fan; a quiet, high-pitched whine that first rises in pitch as it speeds up, then steady for a few seconds, then falls away as it slows to silent again.
At first I thought I must be dreaming it, but I've heard it often enough now to be certain it's real. The problem is that, by the time I'm awake enough to be aware, it's only a few seconds before it stops again and I can't get to the boiler in time to check the display.
My timeswitch is definitely NOT calling for heating or water in the small hours. I've never heard it twice in the same night and I reckon it's probably only occasional nights it does it.
I rang Vaillant's homeowner technical line and all they could suggest was that it might be something to do with the boiler entering "burner anti-cycling" mode, and to look for an egg-timer icon on the display. But they couldn't explain why a boiler that had last fired at least 6-8 hours previously would suddenly decide to enter this mode (nor why it would lead to the fan starting up briefly).
Anyone come across this before?
