SYSTEM TO PREVENT FREEZING OF HEATING UNITS SUCH AS BOILERS

• US 3,812,872 A
• Filed: 06/22/1972
• Issued: 05/28/1974
• Est. Priority Date: 06/22/1972
• Status: Expired due to Term

• Current Assignee: Kenneth F. Vodraska, Larry J. Ashton, Leo Block
• Original Assignee: Kenneth F. Vodraska, Larry J. Ashton, Leo Block
• Inventors: Ashton, Larry J., Block, Leo, Vodraska, Kenneth F.
• Primary Examiner(s): Cohan, Alan
• Assistant Examiner(s): Gerard, Richard
• Application Number:
  US05/265,125
• Time in Patent Office: 705 Days
• Field of Search: 137/59-62,301,570 251/144 165/71 237/80 123/41.14
• US Class Current: 137/62
• CPC Class Codes: E03B 7/10 Devices preventing bursting of pipes by freezing devices preventing bursting of pipes in general F16L55/00
• CPC Class Codes: Y10T 137/1298 Stop and waste
• CPC Class Codes: Y10T 137/1353 Low temperature responsive drains

Abstract

A control system to prevent freezing of heating units, such as boilers, particularly those which may be outdoors, such as on a rooftop. A drain valve is provided to automatically drain the water from the unit in the event of power failure which would prevent heating of the water, or in the event of the occurrence of a low temperature of the water approaching freezing, or both. The system may also include a valve which closes in response to one or both of these conditions to prevent admission of water to the unit. The drain valve embodies a time delay feature so as to not respond to power failures of minimum predetermined duration.

Claims

1. A freeze damage prevention system for a heating unit for heating water and the like wherein said unit is situated to be subject to damage from freezing of the liquid within it, the system comprising:

normally closed valve means connected to the unit in a position whereby to drain the liquid from the unit sufficiently to prevent damage from freezing in the unit; and

means controlling said valve means responsive to a condition indicative of possible or imminent freezing of liquid within the unit, said responsive means comprising mechanism actuatable in response to power failure whereby to cause said normally closed valve to open, said valve means embodying a time delay mechanism whereby said valve means is prevented from opening in response to a power failure of a predetermined relatively short duration.