Upper alternating current draught fan speed regulating system of gas water heater

Abstract

The invention discloses an upper alternating current draught fan speed regulating system of a gas water heater. The upper alternating current draught fan speed regulating system of the gas water heater comprises a controller, a single phase alternating current program guidance (PG) motor, a controllable transwitch circuit, a motor speed feedback circuit and a zero cross detection circuit, wherein the controllable transwitch circuit, the motor speed feedback circuit and the zero cross detection circuit are respectively connected with the controller. The upper alternating current draught fan speed regulating system of the gas water heater aims at achieving stepless speed regulating of the single phase alternating current PG motor through controlling the size of an electrical angle between the controllable transwitch circuit which is connected with the single phase alternating current PG motor and an alternating current zero crossing point, a well-matched state of gas and air is achieved, and the defects of a draught fan with fixed gears has limited gears are overcome, and problems that burning instability and flameouts of a water heater when air quality is too large or too small and the like are solved.

Description

[technical field] [0001] The invention relates to the field of an AC fan for a gas water heater, in particular to a speed regulating system for an AC fan on a gas water heater. [Background technique] [0002] The traditional AC fans for gas water heaters are single-speed fans, which cannot be adjusted in speed. In order to meet the air supply requirements of gas water heaters under the maximum heat load, the wind speed is generally relatively high, which leads to excessive air volume, unstable combustion, and even flameout when the water heater works under a small load state. In order to solve this problem, a two-speed fan has appeared in the industry. The principle is to divide the fan into high and low gears by arranging taps on the motor coil. This technology basically solves the problems of unstable combustion and flameout of water heaters at small loads, but there will still be poor matching of gas and air for intermediate loads. [0003] Therefore, it is necessary to...

AI Technical Summary

Problems solved by technology

[0004] The present invention overcomes the deficiencies of the above-mentioned technologies, and provides a speed-regulating system for an AC fan on a gas water heater, which controls the electrical angle between the thyristor switch circuit connected to the single-phase AC PG motor and the zero-crossing point of the AC according to the setting , to achieve stepless speed regulation of the single-phase AC PG motor, to achieve a good match between gas and air, which changes the disadvantages of fixed gear fans in limited gears, and solves the problem of burning water heaters when the air volume is too large or too small Stability and flameout issues

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