System and a method for controlling variable speed blower

Abstract

Systems and methods for controlling a variable speed blower of a gas-fired heater associated with a swimming pool or spa are provided. A gas heater may include an air-fuel mixture chamber and a circuit. The circuit may be configured to receive a signal to initiate heating water and output a first control signal that operates a variable speed blower associated with the gas heater at a first rate of speed for a first time duration during ignition of the gas heater. The variable speed blower draws air into the air-fuel mixture chamber where the air is combined with gas fuel to ignite the air and the gas fuel to heat the water. The circuit may also be configured to output a second control signal that operates the variable speed blower at a second rate of speed after the first time duration has expired and after the gas heater is ignited.

What is claimed is: 
     
         1 . A gas heater associated with a swimming pool or spa, the gas heater comprising:
 an air-fuel mixture chamber; and   a circuit configured to:
 receive a signal to initiate heating water of the swimming pool or spa; 
 output a first control signal that operates a variable speed blower associated with the gas heater at a first rate of speed for a first time duration during ignition of the gas heater, wherein the variable speed blower draws ambient air into the air-fuel mixture chamber, wherein air drawn in by the variable speed blower is combined with gas fuel in the air-fuel mixture chamber to ignite the air and the gas fuel to heat the water of the swimming pool or spa; and 
 output a second control signal that operates the variable speed blower at a second rate of speed after the first time duration has expired and after the gas heater is ignited. 
   
     
     
         2 . The gas heater of  claim 1 , wherein the first rate of speed is less than the second rate of speed to increase an air-to-fuel ratio (AFR) of the air and fuel mixture and to reduce an ignition energy required to ignite the air and fuel mixture. 
     
     
         3 . The gas heater of  claim 1 , wherein the second rate of speed is less than the first rate of speed to reduce heat emitted by the gas heater. 
     
     
         4 . The gas heater of  claim 1 , wherein the first rate of speed is about 1,500 to about 3,000 rotations per minute and the second rate of speed is about 3,200 to about 3,800 rotations per minute. 
     
     
         5 . The gas heater of  claim 1 , wherein the circuit is further configured to:
 control a rotational speed of the variable speed blower, and wherein the circuit comprises a triode for alternating current (TRIAC) circuit, a Brushless direct current (DC) electric motor (BLDC), or a variable frequency drive (VFD) circuit.   
     
     
         6 . The gas heater of  claim 5 , wherein the circuit is further configured to:
 reduce a voltage associated with the variable speed blower to zero near a zero-voltage crossing for a second time duration to reduce a root mean square (RMS) voltage.   
     
     
         7 . The gas heater of  claim 5 , wherein the circuit is the TRIAC circuit, and wherein the TRIAC circuit reduces a duration of zero voltage near a zero-voltage crossing to ramp up the first rate of speed or the second rate of speed. 
     
     
         8 . The gas heater of  claim 1 , further comprising:
 at least one of a carbon monoxide (CO) sensor, a carbon dioxide (CO 2 ) sensor, or an oxygen (O 2 ) sensor; and   an end-of-line (EOL) tester configured to set a rotational speed of the variable speed blower based at least in part on one or more readings received from the at least one of the CO sensor, the CO 2  sensor, or the O 2  sensor.   
     
     
         9 . The gas heater of  claim 1 , wherein the air-fuel mixture chamber further comprises:
 an air orifice, wherein the circuit is further configured to operate the air orifice to adjust an amount of ambient air drawn into the air-fuel mixture chamber.   
     
     
         10 . A method for controlling a variable speed blower associated with a gas heater, the method comprising:
 receiving a signal to initiate the gas heater associated with a swimming pool or spa, wherein the gas heater heats water of the swimming pool or spa;   operating the variable speed blower associated with the gas heater at a first rate of speed for a first time duration during ignition of the gas heater, wherein the variable speed blower draws ambient air into an air-fuel mixture chamber of the gas heater, the ambient air drawn by the variable speed blower is combined with gas fuel in the air-fuel mixture chamber to produce an air and fuel mixture, and the air and fuel mixture is ignited; and   operating the variable speed blower at a second rate of speed after the first time duration has expired and after the gas heater is ignited.   
     
     
         11 . The method of  claim 10 , wherein the first rate of speed is less than the second rate of speed to increase an air-to-fuel ratio (AFR) of the air and fuel mixture and to reduce an ignition energy required to ignite the air and fuel mixture. 
     
     
         12 . The method of  claim 10 , wherein the second rate of speed is less than the first rate of speed to reduce heat emitted by the gas heater. 
     
     
         13 . The method of  claim 10 , wherein the first rate of speed is about 1,500 to about 3,000 rotations per minute and the second rate of speed is about 3,200 to about 3,800 rotations per minute. 
     
     
         14 . The method of  claim 10 , wherein a rotational speed of the variable speed blower is controlled using a circuit, the circuit corresponds to a triode for alternating current (TRIAC) circuit, a Brushless direct current (DC) electric motor (BLDC), or a variable frequency drive (VFD) circuit. 
     
     
         15 . The method of  claim 14 , wherein the circuit reduces a voltage associated with the variable speed blower to zero near a zero-voltage crossing for a predefined duration of time to reduce a root mean square (RMS) voltage. 
     
     
         16 . The method of  claim 14 , wherein the circuit is provided in the form of the TRIAC circuit that reduces a duration of zero voltage near a zero-voltage crossing to ramp up the first rate of speed or the second rate of speed. 
     
     
         17 . The method of  claim 10 , wherein a rotational speed of the variable speed blower is set by an end-of-line (EOL) tester based on one or more readings received from at least one of a carbon monoxide (CO) sensor, a carbon dioxide (CO 2 ) sensor, or an oxygen (O 2 ) sensor. 
     
     
         18 . The method of  claim 10 , further comprising:
 adjusting an air orifice of the air-fuel mixture chamber to change an amount of ambient air drawn into the air-fuel mixture chamber.   
     
     
         19 . A gas heater, comprising:
 a heater housing having a variable speed blower and an air-fuel mixture chamber;   a controller designed to:
 receive a signal to initiate heating water of a swimming pool or spa; 
 output a first control signal that operates the variable speed blower associated with the gas heater at a first speed for a first time duration during ignition of the gas heater, wherein the variable speed blower draws ambient air into the air-fuel mixture chamber of the gas heater device, and wherein air drawn by the variable speed blower is combined with gas fuel in the air-fuel mixture chamber to ignite the air and the gas fuel to heat the water of the swimming pool or spa; and 
 output a second control signal that adjusts the first speed of the variable speed blower after the first time duration has expired and after the gas heater is ignited. 
   
     
     
         20 . The gas heater device of  claim 19 , wherein the controller:
 adjusts the first speed to a second speed higher than the first speed to increase an air-to-fuel ratio (AFR) of the air and fuel mixture and to reduce an ignition energy required to ignite the air-fuel mixture; and   adjusts the first speed to a third speed lower than the first speed to reduce heat emitted by the gas heater.