CONTROL SYSTEM FOR MULTIPLE ZONE HEATING AND COOLING

• US 3,838,733 A
• Filed: 08/01/1973
• Issued: 10/01/1974
• Est. Priority Date: 08/01/1973
• Status: Expired due to Term

• Current Assignee: American Standard Companies Incorporated (Ideal Standard International Topco SCA)
• Original Assignee: Charles W. Erlandson
• Inventors: Erlandson, Charles W.
• Primary Examiner(s): Sukalo, Charles
• Application Number:
  US05/384,884
• Time in Patent Office: 426 Days
• Field of Search: 165/2,22,80,26,27,28
• US Class Current: 165/215
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: G05D 23/275 with sensing element expanding, contracting, or fusing in response to changes of temperature

Abstract

A multiple-zone air conditioning system including a central heating source and a central cooling source for supplying conditioned air to a plurality of zones includes control circuitry comprising thermostat control means in each zone for operating the cooling source upon the call for cooling by any zone thermostat but operating the heating source only when all zone thermostats call for heating. Auxiliary zone heaters are provided for reheating cooling source air supplied to any zone when its thermostat calls for heating or less cooling.

Claims

1. A multiple-zone air conditioning system comprising a central source for supplying either cooled or heated air to all of said zones:

a zone thermostat means in each of said zones;

control circuitry for supplying cooled air from said source upon a call therefor by any one of said zone thermostat means and supplying heated air to said zones only upon the call therefor by all of said zone thermostat means;

a zone auxiliary heater in at least one of said zones and control means for energizing said zone heater upon the call for heating by the thermostat means in said one of said zones regardless of the requirements of another of said zones.

2. A system according to claim 1 in which said control circuitry thermostat means include heating contacts connected in series for controlling the supply of heated air.

3. A system according to claim 1 in which said thermostat means are two-stage thermostats.

4. A multiple-zone air conditioning system comprising:

a central source of conditioned air including cooling means and heating means;

a zone means in each zone for receiving conditioned air from said central source, each of said means including auxiliary zone heating means;

control circuitry for controlling the operation of said central source cooling and heating means and said auxiliary zone heating means;

said circuitry including temperature control means including a thermostat in each zone responsive to the temperature of that zone;

each of said temperature control means including central cooling control means, central heating control switch means and zone unit heat control switch means for operating said central source cooling means upon the call for cooling by any thermostat and operating said central source heating means only when all of said thermostats call for heating and individually operating an auxiliary zone heating means upon a call for heating by that zone;

said heating control switch means being series connected and said cooling control switch means being parallel connected.

5. A system according to claim 4 in which said thermostat is a two-stage thermostat and one of said control switch means is operated by the first stage of the thermostat and the other control switch means is operated by the second stage.

6. A multiple-zone air conditioning system comprising:

a central source of conditioned air including cooling means and heating means;

a zone means in each zone for supplying conditioned air from said central source to a zone, each of said zone means including auxiliary zone heating means;

control circuitry for controlling the operation of said central source cooling and heating means and said auxiliary zone heating means;

said circuitry including temperature control means including a two-stage thermostat in each zone responsive to the temperature of that zone;

each of said temperature control means including central heating control switch means, central cooling control switch means, and zone heating control switch means for operating said central source cooling means upon the call for cooling by any thermostat means, operating said central source heating means only when all of said thermostat means call for heating and individually operating an auxiliary zone heating means upon a call for heating by that zone;

each of said thermOstat includes first stage heating contacts and second stage cooling contacts;

said control circuitry includes a normally closed zone heating relay de-energized by closing the first stage contacts and a normally open cooling relay controlled by the second stage thermostat contacts, the normally closed contacts of the zone heating relays being series connected.

7. A system according to claim 6 in which each zone heating relay also includes second normally closed contacts for energizing said zone unit heating means.

8. A system according to claim 7 including switch means responsive to the temperature of the central source air supplied to a zone for controlling the energization of said auxiliary zone heating means.