Potterton Netaheat 80E - Thermal trip

[Hangarpilot]

I have a Potterton Netaheat 80E boiler. It keeps tripping and keepgoing back to reset the little button underneath. It works fine for a short while and then trips again. Yesterday i changed the CH pump as i was told that the pump impellor may be broken although it may seem to be working. Anyway this did not help and i am still getting the thermal trip constantly. Please HELP! someone. I have little kids and a baby and I would like to get this sorted. Thanks.

 

[bathjobby]

I can see why the pump was suggested as if there is a loss of flow (pump duff, airlock, etc) then this would cause trip. The bottom line is the boiler is over heating. Has this just started to happen ? if so, what has changed ? e.g. have you turned the boiler stat up, etc ? How old is the system ? are you in a hard water area, has the system been treated with inhibitor ?
Reason for all that is if you have gunge in your system (sitting in the heat exchanger) this could cause the trip. Also, these boilers have many mentions here of tripping on any boiler setting above 3 1/5 which is where I run mine and still get the very odd trip (and mine is a clean system), anything above 3 1/2 increases the trip rate.

 

[Hangarpilot]

Thanks for your reply. I had this problem occur about 4 years ago and then it was a CH pump that had failed. On this occasion i have had a new radiator installed by a chap in the conservatory and he pushed up the boiler to MAX. The trips started after this. I came home from work and turned it back down to 3 where it was originally. But the trips persist. I then asked a friend at work and he suggested the CH pump was u/s. So i changed that yesterday but to no avail . Incidentally the new radiator fails to get hot comletely except for the top rail. That's why the chap put up the boiler to MAX...he claimed the water was at too low a temperature. It was not though and i feel this guy was a cowboy. However i failed to notice his spurs. I have bled the radiator but no good. My system seems quite clean and i had put in inhibitor 2 years ago.

 

[Hangarpilot]

Just for your info ... i have actually reduced the temp setting on the boiler to 2 1/2 but the boiler still trips after a few minutes of running. Please can anyone out there shed some light on this. Do you think my boiler is dying? It is about 10 - 12 years old. If i was to change the boiler... can anyone suggest a good boiler to purchase...one that is reliable as well as efficient please. Thanks.

 

[Agile]

I wish I had a "chap in the conservatory" who I can call on to fit radiators!

Tony

 

[gstens baxi]

Have you checked that there is water in the system.