Hi Guys,
Sorry if it’s too long story just trying to highlight what was/is the problem of my Potterton Puma 100e and what I have done so far to resolve it. Hope this helps finding real culprit.
Had moved to the property since couple of years, serviced the boiler when moved in to the property and guess at that time DHW was too hot so engineer replaced a DHW temperature sensor (guess that was the one replaced)… but then since few months back boiler started to make noises and go to lockout intermittently. I serviced the boiler very recently but chap really didn’t check much (i.e. only cleaned the gas injectors, no other checking
, very disappointed)…but after his visit problem appeared to be more frequent (I am sure he didn’t’ do any thing in settings as he never touch anything, but just problem frequency gone up);
* It was doing grumbling noises and couple of lockout before start to normal (specially when DHW/CH was started first time in morning), then it used to run ok during rest of the day at start of the problem but recently noise/lockout became more frequent; also CH was locking out few times a day.
* I notice that AVV was leaking after each noise and splattering small amount of water/steam-vapor…so I knew water pressure was reducing slightly after each noise/AVV leak. So far, I had to re-pressurise the CH loop couple of times as it dropped/leaked below threshold of 0.5bar after charging to 1 bar.
These were the signs of initial problem and I tried to rectify by doing as below;
* Thought water could boiling or getting too hot, so checked DHW sensor and realise that one of the cable connector was bit loose so fixed that
* Also notice that red led (for flow) was shutting off after certain delay (not really instantaneously, not too much of delay but may be delay of around 2-3 seconds i.e. after shutting full HW flow). So to check if its sticking, I hinged down the front panel…I think it wasn't sticking but notice that micro switch was fully screwed in to flow switch (guess manual says something about 4.5 to 5mm of gap between flow switch face to micro switch face). So, I assume boiler was may be overheating and thus noise, steaming and lockout. so I unscrewed micro switch a bit and made this distance to around 6mm (making micro switch sensitive to the flow) - however can't understand why this problem appeared suddenly as I guess micro-switch was always fully inserted and boiler was working fine so far...!!
Apparently after doing so, surprisingly problem of noise and too hot water looked disappeared. Water was coming nicely hot (not scalding hot, it was too hot earlier). And as soon as tap is off; instantaneously red led turns off. So I thought micro switch setting (or minor sticking flow switch) was the problem and system run OK for a week or two…during this time; no sign of noises, no more dripping from AVV (note that it was the same AVV which was leaking earlier, I actually bought new but never fitted since no more water was leaking through AVV).
However, during CH mode I notice that burner/flame turn on and off couple off times before it’s in full swing. Am I correct assuming that this is normal (this mainly happens when CH heating starts initially, I am not sure if this is how it suppose to be)?
Then....
I notice that our shower was started to leak very slowly. So, CH was kicking in and out constantly (initially didn’t knew why) but as soon as I turn the mains water tap off (to stop shower leaking), CH heating started as normal without any problem/noise/no AVV leak. So, last week I got the new thermostatic shower, installed all OK but now notice that temperature was fluctuating from hot/cold/hot and so on
And that’s where my another issue appeared!!
* Initially though, this is a shower problem and also showerhead was not giving much flow so I replaced it with old one just to try; and flow and pressure was good and temp fluctuation stopped, which ruled out faulty shower mixer.
* Put back old showerhead and problem appeared again. At this instance, I looked back to the boiler and observed that boiler flame was switching on and off after few minutes (red led was constantly showing flow though). Initially boiler flame was low as the start, but after a minute (or less) it turned full, as soon as it turned full and run for a minute (or less) it cut off, and once DHW is fully cold, flame turned on again, so this was cycling constantly!
* To do more check; tried opening kitchen tap partially (simulating low flow) – red led came on, boiler started as usual but again cut off after a minute (or less) and kicked on again until water was completely cold. So, same temperature swinging problem…
* At this instance, observing on flow switch indicated that once flow and flame is fully established, flow switch spindle was moving inward slightly (this may be due to heat/cold water expansion or high/low flow through flow switch, so may be this slight movement was disengaging micro switch). Assumed flow switch/micro switch setting is too sensitive. So I changed the flow switch/micro switch distance setting to around 5mm.
* Doing this did not resolve temperature swinging problem!!
* But as soon as I open the hot water tap fully (or switch back to old showerhead), hot water run through normal with almost constant temperature (but still too hot I believe).
* I notice that temperature of DHW is quite hotter then before (i.e. compared to when I had flow/micro switch setting of 5.5/6mm). Can't understand logic here unless DHW temp sensor is playing up again.
* I do not know if the temperature swinging problem was exist since start; as never really tried/observe the situation with partially open tap and also previous showerhead was having high flow so no issue was observed or don’t know if its recently developed problem.
* Temporarily, I have plugged back old showerhead just to get decent shower but I think I would need to nail down this problem before it grows more.
Looking through forum, HX scaling could be a problem but we do get soft water and not sure if that would scale the HX and guess CH water may be treated with Sentinel X100 seeing label on boiler front fascia – I do not have much history but I have not drained the system yet to check this (assume this is bit long process, never vented the system, so kept it as last or if this is likely the problem)
Now, I am not sure how to go from here and what to check further!!
Hugely appreciate any comments or assistance from the experts..
Cheers.
Sorry if it’s too long story just trying to highlight what was/is the problem of my Potterton Puma 100e and what I have done so far to resolve it. Hope this helps finding real culprit.
Had moved to the property since couple of years, serviced the boiler when moved in to the property and guess at that time DHW was too hot so engineer replaced a DHW temperature sensor (guess that was the one replaced)… but then since few months back boiler started to make noises and go to lockout intermittently. I serviced the boiler very recently but chap really didn’t check much (i.e. only cleaned the gas injectors, no other checking
, very disappointed)…but after his visit problem appeared to be more frequent (I am sure he didn’t’ do any thing in settings as he never touch anything, but just problem frequency gone up);* It was doing grumbling noises and couple of lockout before start to normal (specially when DHW/CH was started first time in morning), then it used to run ok during rest of the day at start of the problem but recently noise/lockout became more frequent; also CH was locking out few times a day.
* I notice that AVV was leaking after each noise and splattering small amount of water/steam-vapor…so I knew water pressure was reducing slightly after each noise/AVV leak. So far, I had to re-pressurise the CH loop couple of times as it dropped/leaked below threshold of 0.5bar after charging to 1 bar.
These were the signs of initial problem and I tried to rectify by doing as below;
* Thought water could boiling or getting too hot, so checked DHW sensor and realise that one of the cable connector was bit loose so fixed that
* Also notice that red led (for flow) was shutting off after certain delay (not really instantaneously, not too much of delay but may be delay of around 2-3 seconds i.e. after shutting full HW flow). So to check if its sticking, I hinged down the front panel…I think it wasn't sticking but notice that micro switch was fully screwed in to flow switch (guess manual says something about 4.5 to 5mm of gap between flow switch face to micro switch face). So, I assume boiler was may be overheating and thus noise, steaming and lockout. so I unscrewed micro switch a bit and made this distance to around 6mm (making micro switch sensitive to the flow) - however can't understand why this problem appeared suddenly as I guess micro-switch was always fully inserted and boiler was working fine so far...!!
Apparently after doing so, surprisingly problem of noise and too hot water looked disappeared. Water was coming nicely hot (not scalding hot, it was too hot earlier). And as soon as tap is off; instantaneously red led turns off. So I thought micro switch setting (or minor sticking flow switch) was the problem and system run OK for a week or two…during this time; no sign of noises, no more dripping from AVV (note that it was the same AVV which was leaking earlier, I actually bought new but never fitted since no more water was leaking through AVV).
However, during CH mode I notice that burner/flame turn on and off couple off times before it’s in full swing. Am I correct assuming that this is normal (this mainly happens when CH heating starts initially, I am not sure if this is how it suppose to be)?
Then....
I notice that our shower was started to leak very slowly. So, CH was kicking in and out constantly (initially didn’t knew why) but as soon as I turn the mains water tap off (to stop shower leaking), CH heating started as normal without any problem/noise/no AVV leak. So, last week I got the new thermostatic shower, installed all OK but now notice that temperature was fluctuating from hot/cold/hot and so on
And that’s where my another issue appeared!!
* Initially though, this is a shower problem and also showerhead was not giving much flow so I replaced it with old one just to try; and flow and pressure was good and temp fluctuation stopped, which ruled out faulty shower mixer.
* Put back old showerhead and problem appeared again. At this instance, I looked back to the boiler and observed that boiler flame was switching on and off after few minutes (red led was constantly showing flow though). Initially boiler flame was low as the start, but after a minute (or less) it turned full, as soon as it turned full and run for a minute (or less) it cut off, and once DHW is fully cold, flame turned on again, so this was cycling constantly!
* To do more check; tried opening kitchen tap partially (simulating low flow) – red led came on, boiler started as usual but again cut off after a minute (or less) and kicked on again until water was completely cold. So, same temperature swinging problem…
* At this instance, observing on flow switch indicated that once flow and flame is fully established, flow switch spindle was moving inward slightly (this may be due to heat/cold water expansion or high/low flow through flow switch, so may be this slight movement was disengaging micro switch). Assumed flow switch/micro switch setting is too sensitive. So I changed the flow switch/micro switch distance setting to around 5mm.
* Doing this did not resolve temperature swinging problem!!
* But as soon as I open the hot water tap fully (or switch back to old showerhead), hot water run through normal with almost constant temperature (but still too hot I believe).
* I notice that temperature of DHW is quite hotter then before (i.e. compared to when I had flow/micro switch setting of 5.5/6mm). Can't understand logic here unless DHW temp sensor is playing up again.
* I do not know if the temperature swinging problem was exist since start; as never really tried/observe the situation with partially open tap and also previous showerhead was having high flow so no issue was observed or don’t know if its recently developed problem.
* Temporarily, I have plugged back old showerhead just to get decent shower but I think I would need to nail down this problem before it grows more.
Looking through forum, HX scaling could be a problem but we do get soft water and not sure if that would scale the HX and guess CH water may be treated with Sentinel X100 seeing label on boiler front fascia – I do not have much history but I have not drained the system yet to check this (assume this is bit long process, never vented the system, so kept it as last or if this is likely the problem)
Now, I am not sure how to go from here and what to check further!!
Hugely appreciate any comments or assistance from the experts..
Cheers.
