My Baxi 100/2 HE boiler fires up for 20 -30 mins then cuts out on lockout. It started intermittently, hot water and ch operate ok for the time it stays on, now it locks out every time. The pump keeps running after lockout. I have bled the radiators. When I reset after cooling it restarts for another 30 mins then locks out. Its 3 years old and serviced 15 months ago.
Trouble shoot manual says possibly stat or thermistor this model is not a combi and has no pressure guage, ...Any ideas ?

Neville Newmarch, December 2008

This usually happens after replacing burner, this fault is usually seal related either after fitting new burner and the seal between the burner and fan not correct or door seal combustion chamber not air box perished, hot gases from combustion chamber are entering the airbox and so tripping the fan stat, if using an analyser would be represented by higher than usual co2 reading above 10.

The Boilermyster, November 2010

Look at this http://www.ukplumbersforums.co.uk/central-heating-forum/6540-baxi-100-he-condesing-boiler.html

S Ford, October 2010

Got it fixed everyone!
It was a combinations of flow stat on the boiler and the seal around the fire box had perished, hot air from the fire box was being sucked into the fan box and tripping the fan stat..RESULT thanks to an intrepid tenacious engineer!!

Nev the question asker, March 2009

Depends what lock out you have. Have you got the user manual ie one with a fault finding flow chart?

Bogart, January 2009

Hi, It not much help to you but I am experiencing the same problems with Baxi 100 HE boiler which is 3 years old. Have had plumber replace pump and this worked for a while but same symtoms have returned. I have heat store connected to boiler which is probably different to your set up. My plumber is checking the set up with Baxi but did you get any joy with your boiler?

Mark Capel, January 2009

boiler is overheating, water may not be circulating through it quick enough. make sure pump is on full and free from air. having trv on all rads would stop flow if have them

slop, December 2008