Hi,
This is my first plumbing post, so apologies if I don't describe the the problem very well.
I have an Ariston 27 mffi which works well most of the time. Last winter it started locking out (red light near reset button) intermittently when you turn off the dhw. It happens most often when you've been having a shower, which I guess is when it's been on for a long time. It's been fine all summer, but it's started doing the same thing again since the heating's been on again. It seems to get more frequent as the heating season goes on.
Pressing the reset button has no effect unless you turn on the hot water or the heating momentarily (which of course runs cold). It will then reset absolutely fine and work well for a while until it catches you out again.
I'm pretty handy in general, but I know little about boilers. I've previously added an external expansion vessel to the system when the last one went wrong but that's about it.
I had a search around and think it might be something sticking open. Maybe the diverter valve, or the dhw flow switch. I thought if the flow switch stuck open it might cause overheating because there's no water to heat hence the lockout.
Does this jump out at anyone as something obvious thats wrong, or perhaps I'm completely off the mark with my guessing!
Please help! I want to avoid the hassle and cost of calling someone out if I can, as I know I can fix it if it's something simplish.
This is my first plumbing post, so apologies if I don't describe the the problem very well.
I have an Ariston 27 mffi which works well most of the time. Last winter it started locking out (red light near reset button) intermittently when you turn off the dhw. It happens most often when you've been having a shower, which I guess is when it's been on for a long time. It's been fine all summer, but it's started doing the same thing again since the heating's been on again. It seems to get more frequent as the heating season goes on.
Pressing the reset button has no effect unless you turn on the hot water or the heating momentarily (which of course runs cold). It will then reset absolutely fine and work well for a while until it catches you out again.
I'm pretty handy in general, but I know little about boilers. I've previously added an external expansion vessel to the system when the last one went wrong but that's about it.
I had a search around and think it might be something sticking open. Maybe the diverter valve, or the dhw flow switch. I thought if the flow switch stuck open it might cause overheating because there's no water to heat hence the lockout.
Does this jump out at anyone as something obvious thats wrong, or perhaps I'm completely off the mark with my guessing!
Please help! I want to avoid the hassle and cost of calling someone out if I can, as I know I can fix it if it's something simplish.
