Granted Patent B2

US 7,236,692 · App. 11/002,962 · Granted Jun 26, 2007

Abstract

Claims (38)

1. A method of controlling a spa heater, comprising:

determining a current drawn by non-heater components of the spa;

calculating an available current capacity for the heater;

controlling a current drawn by the heater to equal approximately the available current capacity for the heater;

receiving a signal to change the state of one of the non-heater components;

de-energizing the heater prior to changing the state of the one of the non-heater components;

changing the state of the one of the non-heater components; and

determining the current drawn by the non-heater components after changing the state of the one of the non-heater components.

2. The method of claim 1 , wherein controlling the current drawn by the heater comprises setting the timing of a plurality of consecutive voltage gate pulses to a triac to control the time during each of a plurality of consecutive AC cycles during which the heater can draw current.

3. The method of claim 1 , wherein controlling the current drawn by the heater comprises setting the timing of a plurality of consecutive voltage gate pulses to a triac to control the time during each of a plurality of consecutive AC cycles during which the heater draws current.

4. The method of claim 1 , further comprising:

receiving a start heating signal; and

determining the current drawn by the non-heater components prior to energizing the heater.

5. A method of controlling an electrically-powered heater in a bathing installation including a recirculating water flow path in fluidic communication with a bathing installation vessel for holding water and electrically-powered non-heater components, the method comprising:

receiving a signal to change the state of one of the non-heater components;

de-energizing the heater prior to changing the state of the one of the non-heater components;

changing the state of the one of the non-heater components;

determining the current drawn by the non-heater components after changing the state of the one of the non-heater components

calculating an available current capacity for the heater;

controlling a current drawn by the heater to so that said current does not exceed the available current capacity for the heater.

6. The method of claim 5 , wherein said determining a current drawn by the non-heater components comprises measuring the current being drawn by the bathing installation using a current sensor.

7. The method of claim 5 , further comprising:

receiving a start heating signal; and

determining the current drawn by the non-heater components prior to energizing the heater.

8. A bathing installation, comprising:

an electrically-powered heater;

a bathing installation vessel for holding water;

a recirculating water flow path in fluidic communication with the bathing installation vessel and the heater;

electrically-powered non-heater components;

a microprocessor-based control system, comprising:

a control algorithm for controlling the heater and the non-heater components to control a bathing installation environment including temperature of the bathing installation water;

means for changing the state of one of the non-heater components in response to a received signal or pursuant to the control algorithm;

means for de-energizing the heater prior to changing the state of the one of the non-heater components;

means for determining the current drawn by the non-heater components after changing the state of the one of the non-heater components while the heater is de-activated;

means for calculating an available current capacity for the heater;

means for activating the heater and controlling a current drawn by the heater to so that said current does not exceed the available current capacity for the heater.

9. The installation of claim 8 , wherein the means for determining the current drawn by the non-heater components comprises a current sensor for measuring the current drawn by the installation.

10. The installation of claim 8 , wherein the means for determining the current drawn by the non-heater components comprises means for calculating the current drawn by non-heater components responsive, at least in part, to a table of nominal current usage values stored in a memory.

Assignments (12)