Method of controlling a space heating system

Claim 1

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds, said; repetitively, intermittently energizing said controller heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count.

Claim 2

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds, said; repetitively, intermittently energizing said controller heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count.

Claim 5

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds, and; repetitively, intermittently energizing said controlled heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count, said intermittent energization of said controlled heater being repetitive over a plurality of sequentially-occurring cycle times, said intermittent energization being by digital signals directed to an electronic circuit adapted for controllably coupling and uncoupling said modulated heater to an alternating voltage line; said electronic circuit being adapted for controllably switching a triac and said coupling and uncoupling is permitted to occur only within brief periods of time during which said alternating voltage is closely proximate to a zero voltage reference axis, thereby reducing spurious radio frequency interference.

Claim 6

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds, and; repetitively, intermittently energizing said controlled heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count, said intermittent energization of said controlled heater being repetitive over a plurality of sequentially-occurring cycle times, said intermittent energization being by digital signals directed to an electronic circuit adapted for controllably coupling and uncoupling said modulated heater to an alternating voltage line; said electronic circuit being adapted for controllably switching a triac and said coupling and uncoupling is permitted to occur only within brief periods of time during which said alternating voltage is closely proximate to a zero voltage reference axis, thereby reducing spurious radio frequency interference.

Claim 7

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds; repetitively, intermittently energizing said controller heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count; said aggregate number further including an integer component and said method further including the step of continuously energizing a number of second resistance heaters, said number being equal to said integer component; said computing step including the steps of: generating a command signal representative of the difference between said set point temperature signal and said actual temperature signal; generating a response signal representative of the difference between said aggregate number of resistance heaters required to be energized and an aggregate number of resistance heaters then actually energized; detecting any error between said command signal and said response signal, and; energizing at least one of said second resistance heaters, thereby eliminating said detected error.

Claim 8

A method of controlling a space heating system having a first controlled resistance heater adapted for modulated control by intermittent energization, and a plurality of second resistance heaters, said method including the steps of: selecting a total bit count representative of the entire heating capacity of said heating system; generating a signal representative of a set point temperature to be maintained within a space; generating a signal representative of the actual temperature within said space; computing the aggregate number of said resistance heaters required to be energized to raise said actual temperature to a value equivalent to said set point temperature, said aggregate number including a fractional component; resolving said fractional component to a first bit count representative of a portion of a cycle time during which said controlled heater is to be energized, said cycle time being at least one second and not greater than thirty seconds; repetitively, intermittently energizing said controller heater over said cycle time, said controlled heater being energized for that portion of said cycle time represented by said first bit count, said controlled heater being de-energized for that portion of said cycle time represented by the difference between said total bit count and said first bit count; said aggregate number further including an integer component and said method further including the step of continuously energizing a number of second resistance heaters, said number being equal to said integer component; said computing step including the steps of: generating a command signal representative of the difference between said set point temperature signal and said actual temperature signal; generating a response signal representative of the difference between said aggregate number of resistance heaters required to be energized and an aggregate number of resistance heaters then actually energized; detecting any error between said command signal and said response signal, and; energizing at least one of said second resistance heaters, thereby eliminating said detected error.