" I called Coelho and left a message, not altogether hopeful at this point. He called back in like 10 minutes. We talked on the phone for maybe 20 minutes while he had me do a couple of simple diagnostic tests and decided that while the fault was a minor sensor, that I had best leave it to him. Fine with me at my age. 30 minutes later he pulls up outside in the family 4x4. 20 minutes later he has fixed the faulty sensor, the boiler is getting hotter by the minute and all is well. It's now 3 hours later, the house is cozy warm, and I am very glad I had him put the new furnace in the first place.