- Joined
- 1 Jul 2018
- Messages
- 4
- Reaction score
- 0
- Country
Good Morning,
I'm new to this forum and joined after much frustration with trying to fix this boiler.
Im mechanical engineer so pretty hands on with most things but obviously do not knows precise in and outs of boilers but learning fast.
The fault is Dhw does not switch on after period of time most after being left over night and takes multiple resets but then ok for rest of day as regular use. Pump and fans work but flame will not ignite and throws up red fail to ignite Led.
CH works fine and if this is on first then works, not practical in this heat. Lol.
Boiler is 10 years old and in good condition water wise and using magnaclean, always used fernox, regular flushed system as moved rads quite few times. Changed fan and pump last year as they sounded very noisy.
Have extermly good water pressure and soft water area. Was wondering if too good. Ch pressure set at 1 bar.
That is history here is what I've just changed.
Dhw flow switch, flow switch turbine (quite crusty but not terrible), 2 temperature thermisters, over heat stat, secondary heat exchanger (not that dirty at all), air flow switch. Whilst system empty put 1 bar of air in expansion vessel was empty.
This morning ran meter into back of main flow switch shows 4.91 volt and when activate dhw by shorting pink and white of Dhw switch switches everything on and main flow switch then shows 0 volt so this must be working? Also tried applying magnet to the flow switch and whole boiler activates fans pumps etc but will not ignite until 3 or 4 resets.
Done these checks this morning to check the dhw switch side and turbine is not the problem and have being advised to change main flow switch next but as reads 4.9 v then 0 when dhw switch activates I feel this is working.
I should done these checks in hindsight rather then diving in put I listened to Ariston tech advice line and friends.
Help please off you experts that know what your doing what's next.
In my head could new thermisters be faulty do I meter these and turn water on if so what readings looking for. My other thoughts are there relays on pcb that could be playing up. Could the ignite circuit be playing up but then its ok for CH. Why does it work after multiple resets then ok for the day. There not a lot left is there?
Thank you for your time.
I'm new to this forum and joined after much frustration with trying to fix this boiler.
Im mechanical engineer so pretty hands on with most things but obviously do not knows precise in and outs of boilers but learning fast.
The fault is Dhw does not switch on after period of time most after being left over night and takes multiple resets but then ok for rest of day as regular use. Pump and fans work but flame will not ignite and throws up red fail to ignite Led.
CH works fine and if this is on first then works, not practical in this heat. Lol.
Boiler is 10 years old and in good condition water wise and using magnaclean, always used fernox, regular flushed system as moved rads quite few times. Changed fan and pump last year as they sounded very noisy.
Have extermly good water pressure and soft water area. Was wondering if too good. Ch pressure set at 1 bar.
That is history here is what I've just changed.
Dhw flow switch, flow switch turbine (quite crusty but not terrible), 2 temperature thermisters, over heat stat, secondary heat exchanger (not that dirty at all), air flow switch. Whilst system empty put 1 bar of air in expansion vessel was empty.
This morning ran meter into back of main flow switch shows 4.91 volt and when activate dhw by shorting pink and white of Dhw switch switches everything on and main flow switch then shows 0 volt so this must be working? Also tried applying magnet to the flow switch and whole boiler activates fans pumps etc but will not ignite until 3 or 4 resets.
Done these checks this morning to check the dhw switch side and turbine is not the problem and have being advised to change main flow switch next but as reads 4.9 v then 0 when dhw switch activates I feel this is working.
I should done these checks in hindsight rather then diving in put I listened to Ariston tech advice line and friends.
Help please off you experts that know what your doing what's next.
In my head could new thermisters be faulty do I meter these and turn water on if so what readings looking for. My other thoughts are there relays on pcb that could be playing up. Could the ignite circuit be playing up but then its ok for CH. Why does it work after multiple resets then ok for the day. There not a lot left is there?
Thank you for your time.
Last edited:
