Local gas fireplace repair in Callahan

The thermopile and the switch circuit

A thermopile is a bundle of thermocouple junctions wired together, and its larger output does more than hold the valve open: it powers the valve's main operator through the wall switch or remote receiver. That makes the switch circuit part of the fuel system. A long wire run, thin wire, a corroded terminal or a worn switch can each drop enough voltage that the burner will not come on. The maker's chart gives the readings to take at the valve terminals, with the switch open and closed, and a short jumper across the switch shows whether the switch or the wire is at fault.

The glass gasket on a sealed unit

A direct-vent fireplace is sealed from the room, and the glass front, clamped against a gasket, is part of that seal. A gasket that has flattened, torn or come loose leaves a path for exhaust into the room, which is why the manuals say the glass door has to be properly seated and sealed.

On service we check the latches or clamps, look along the whole gasket for gaps and hardening, and replace the gasket with the maker's part when it no longer seals. Damaged glass is replaced as the maker's full assembly. The latches themselves wear, and a latch that no longer pulls the frame tight is replaced too.

Insects in the pilot and air openings

Spiders and small insects are drawn to the pilot tube and the burner air openings of a gas fireplace that sits unused, and a web in the wrong place can starve the pilot or change the air mix at the burner. The manuals call for the burner, the control compartment and the air passages to be kept clean, and to be cleaned more frequently where lint, dust or pet hair is heavy. On a first service after an idle stretch, we clear the pilot tube, the pilot air opening and the burner openings before lighting the unit. Batteries in the receiver are checked for corrosion at the same time.