sabre 29he combi not firing

[kevvilla]

I need some help please. I have a Sabre 29he boiler that was new in Dec 2007, it has run perfect since it was fitted, but now no heating or hot water, i took off the outer white case to take a look,I unclipped the lower clips on the front case with the glass window, pulled the bottom of the panel out slightly, then it sucked in some air in and it worked perfect,i have been doing this for the past few weeks for 10 mins at a time just for hot water to have a shower,i found a bit of info on this site,this was ok untill this method stopped working,then i found that if i took off the top pipe to the air pressure switch it would work again,so i decided to buy a air pressure switch,fitted this today and its still the same,only works if i pull off top pipe,it was mention on here about a blocked venturi something,is this likely to be my case now,2 questions ,1 is this easy to get to and clean or how much would a gas engineer charge me to do this,as money is very low at mo,hence why i tried to fix it myself,thanks in advance,kev

 

[BingoBongo]

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You have also opened the combustion seal which should be checked by a rgi

keep any sort of compressor away from the air pressure switch

 

[kevvilla]

i tried the compressor,no good,so i`ll have to save the money to get an engineer out,thanks for the advice m8 and i`ll let you know what happens soon as