초록 ▼

A dirty filter indicator device adapted for use with a furnace, an air conditioning assembly and the like. As the filter collects dirt and dust, the overall airflow is restricted causing more air to flow through the whistle device. This increased air flow through the device alerts the occupants to t

A dirty filter indicator device adapted for use with a furnace, an air conditioning assembly and the like. As the filter collects dirt and dust, the overall airflow is restricted causing more air to flow through the whistle device. This increased air flow through the device alerts the occupants to the need to change the air filter. The device has a canopy to prevent large dust particles from clogging the device and an adjustable nozzle element which can be adjusted to begin whistling according to the degree of dirtiness of the filter by cutting portions of the distal end of the whistle.

대표청구항 ▼

1. An air filter monitor device for indicating a dirty air filter in an HVAC system, comprising:an elongated tube having a first end and a second end; a conical nozzle attached to the first end of said tube, the nozzle having a discharge orifice, the nozzle defining a conical passage; a cylindrical

1. An air filter monitor device for indicating a dirty air filter in an HVAC system, comprising:an elongated tube having a first end and a second end; a conical nozzle attached to the first end of said tube, the nozzle having a discharge orifice, the nozzle defining a conical passage; a cylindrical hollow flange having a top wall and a bottom wall, the second end of said tube penetrating into the hollow flange through the bottom wall, the hollow flange having an aperture for the ingress of air into the hollow flange defined in the top wall opposite the second end of said tube; and a canopy having a top wall and a skirt depending from the periphery of the top wall, the canopy being in spaced relation from and partially enclosing said hollow flange, the top wall and the skirt covering and surrounding the top wall of said hollow flange; wherein a continuous air passage is defined extending under the skirt of said canopy and through said hollow flange, said tube and said nozzle; and wherein the monitoring device is adapted for insertion through an air filter in an HVAC system, the monitoring device emitting a whistle by an increased airflow under pressure through the air passage when the air filter is overloaded with dirt and dust; said canopy preventing dust from entering said air passage.