Gas fireplace vent repair and installation in Lake Sunset

Vertical rise decides how far the pipe can travel sideways

Direct-vent manuals tie the horizontal run to the vertical rise with a vent graph. In one maker's example, a fireplace whose vent rises 11 feet may run up to 14 feet horizontally to the outside wall, while a 7 foot rise allows no more than 8 1/2 feet.

The graph exists because the intake and exhaust have to stay in balance. When a fireplace is moved or a cap is relocated, our specialists plot the new route on your model's graph before quoting, and they only recommend a layout the maker allows.

Insulation counts as a combustible

It surprises many owners, but one B-vent fireplace manual tells installers to treat insulation as a combustible material and to keep the required clearances to it. The same manual asks for a chase to be insulated like the outside walls of the house.

Those two rules work together. The chase gets insulated, and the vent inside it keeps its air space. When our technicians open an access point, they check both and write down whether the insulation has drifted against the pipe.

Why a B-vent loses its draft

Poor draft has a long list of venting causes in one B-vent fireplace manual, and each one points at a different repair. Our pros work through it in order, since the fix for a short vent is nothing like the fix for a blocked one.

The list below comes from that manual. Several causes can exist on the same house, which is why we check them all before quoting.

• Too much offset or too many elbows
• A vent that is too short or too close to the roof line
• A blockage restricting the pipe
• The wrong vent type or the wrong size
• More than one appliance on one vent

Two liners down an old masonry chimney

Some gas inserts vent through an existing masonry chimney using two flexible liners, one bringing fresh air down and one carrying exhaust up. In one maker's co-linear kit, that means a 3 inch intake liner, a 4 inch exhaust liner, an adapter on the appliance and a co-linear termination with flashing at the top.

The same instructions allow the co-linear part of the vent only inside a solid-fuel-burning fireplace and chimney. Our specialists confirm the chimney qualifies before recommending this route in Lake Sunset.

After a flood or a burst pipe

Gas fireplace manuals are blunt about water. One says a fireplace with any part that has been under water or exposed to it stays off until a qualified technician has inspected it and replaced every control and gas control that was submerged.

Our technicians follow that rule even when the unit seems to light. They check the controls, the burner and the vent, and they list the replacement parts and the vent findings separately so you can see both.