Help: How-to

Venturi Tubes

The venturi tubes are the tubes that extend from the burner to the control valves. These have openings at the ends to allow air to mix with the gas as it leaves the control valve. Generally they are fitted with moveable shutters that allow for air mixture adjustment and with spider guards or small screening to discourage spiders and insects from entering.

• Bugs - Commonly, spiders and small insects will spin webs or build nests inside the venturi tubes. This especially occurs in late summer and fall before frost, when spiders are most active. These nests can obstruct gas flow and cause a fire in and around the valve at the control panel. Such a fire can cause operator injury and serious damage to your grill. To help prevent a blockage and ensure full heat output, clean and inspect venturi tubes often.
• Spider Guards - Screening is often built into the venturi openings to act as a spider guard. Spider guards can be fabricated by wrapping small sections of aluminum screen around the venturi openings and securing with small gauge wire to keep the screens in place. The guards should be cleaned periodically to keep dust from blocking air openings.
  1. Remove burner assembly from grill.
  2. Look inside lower end of venturi tubes for insect nests, cobwebs, or wasp mud.
  3. To remove insect nests, cobwebs or wasp mud, use an accessory flexible venturi brush or bend a small hook on one end of a 20 inch long flexible length of wire.
  4. Use the brush or wire to remove the obstructions from the venture tubes.
  5. Inspect and clean burner if needed.
  6. Replace the burner assembly into the grill.
  7. Make sure valve orifices are inside venturi tubes.

     NOTE: These tubes do not mechanically attach to the valve. Be sure that the valve orifice extends at least 1/4 of an inch into the venture tube.

  8. Secure burner to grill.
• Adjustment - Moveable shutters are a part of most venturi tubes and have a locking screw which when loosened allows the shutter to be rotated, controlling the air and gas mixture and subsequently the burner flame. Some venturi tubes are factory set and have no means of adjustment.

Replacement and inspecting for rust. What to look for....

Corrosion starts at the top of the burner, and usually at the seams where food acids accumulate. If the burner is left unattended and not replaced at an appropriate time the rust will eventually work its way down under the burner to where the venturis attach requiring venturi replacement.

• Twist-Lock venturis.

  Featured on Sunbeam and new model Charmglow grills, the twist-lock venturi is designed for ease of installation and assembly. The venturis are mounted by placing the venturi into the inlet on the burner and twisting the venturi to a perpendicular position. At that point there are two small metal lips on the venturi that lock the venturi into place causing a secure seal. It is common that these lips will corrode which inhibits the venturi from locking securely into place. Although burners of this type are shipped with the collector plate which gives additional support to the venturis, we recommend replacement if the locking lips on the venturis show signs of rust .

• Flange mount venturis.

  The flange mount is the most common type of venturi and has a mounting flange that attaches with two screws or nuts. There is a gasket that goes between the flange and the burner which gives a secure seal. Pitting and rusting of the flange surface may allow gas to escape between the gasket and the flange. If this surface is corroded we recommend replacement of the venturi. As an added note, universal venturis may not fit on original equipment burners because of a difference in the hole pattern on the flange.