Moebius Cat

Furnace has failed yesterday: flame starts, then flames out after 10-15 seconds, after several tries like that (shorter 4-5 second bursts) it shuts of for a couple of hours with an error code, then restarts the cycle. I cleaned the flame sensor, but it didn't help. Called a furnace guy...

Guy came, he was nice and apologetic, took $90 (“just for time and gas”), didn’t fix anything, because the freaking thing was working fine when he came (just my luck)… 2 minutes after he left it flamed off again, so I called and he came back. 30 min. later after checking things – same thing… “Nothing I can do: something occasionally is throwing off the pressure switch. I don’t think it’s a flame sensor. It’s impossible to diagnose precisely as there is a single error core points to three possible problems – flame sensor, pressure switch, condensate blockage. Condensate looks clear, all tubes look clear, flame sensor would shut off much faster. We can replace pressure switch, because it’s old and might be too sensitive, but it might be something else that throws the switch, replacing would costs $250 and I wouldn’t invest money in this furnace, it’s at the end of its life and I hate Keeprite.” New furnace would cost $3-$4K. He cleaned some rubber hoses, found a kink in one hose and shortened it (didn’t help because it shut off after that), tweaked and blew into some hoses, but mostly stared into insides of the thing for a while, just like I did… Said I should drill out (enlarge) two holes where the hoses connect, because there were manufacturer instructions to do so due to manufacturing defect – “who knows, it may help”. Cleaned the flame sensor again (I had to tell him how to take it off BTW, he didn’t know where the clip is). Didn’t help – furnace was working for about 15 minutes after he left, then shut off again…

So, the options are: first try replacing the flame sensor anyway ($US28 plus rush shipping from US – it’s holding at 22C so far, so we’re not freezing) – there is some, but great, chance of it helping, or get a new furnace right away, which we don’t really have money for at the moment :-(

Anyone has any ideas abour what else to try?