Flushing of heating, ventilating and air conditioning systems using environmentally safe materials

• US 5,174,906 A
• Filed: 09/27/1991
• Issued: 12/29/1992
• Est. Priority Date: 09/27/1991
• Status: Expired due to Term

• Current Assignee: Bright Solutions Incorporated (Bright Solutions)
• Original Assignee: ADVANCED RESEARCH & TECHNOLOGY INSTITUTE
• Inventors: Henry, Richard G.
• Primary Examiner(s): Dawson, Robert A.
• Assistant Examiner(s): Fortuna, Ana M.
• Application Number:
  US07/766,124
• Time in Patent Office: 459 Days
• Field of Search: 210/805, 210/804, 210/749, 210/765, 62/303, 62/292, 62/77, 62/85, 252/67, 252/68, 134/22.11, 134/22.19, 134/108
• US Class Current: 210/765
• CPC Class Codes: C09K 5/044 comprising halogenated compounds
• CPC Class Codes: C09K 5/045 containing only fluorine as halogen
• CPC Class Codes: C11D 7/24 Hydrocarbons
• CPC Class Codes: C11D 7/5022 containing oxygen
• CPC Class Codes: C11D 7/5027 Hydrocarbons
• CPC Class Codes: C23G 5/024 containing hydrocarbons
• CPC Class Codes: C23G 5/032 containing oxygen-containing compounds
• CPC Class Codes: F25B 45/00 Arrangements for charging or discharging refrigerant

Abstract

A solvent selected from the terpene hydrocarbon group and terpene alcohol group as a cleaning agent can provide effective cleaning of heating, ventilating and air conditioning systems which use hydrofluorocarbon or hydrochlorofluorocarbon or Freon refrigerants by using a solvent as described. Flushing through the refrigerant system condenser coils and evaporation coils removes any trace of excessive compressor lubricant which will be carried out with the solvent. The flushed materials carried out are biodegradable, thus are desirable from an environmental standpoint.

Claims

1. The process of flushing refrigerant from heating, ventilating and air conditioning systems that employ Freon, hydrofluorocarbon or hydrofluorochlorocarbon as a refrigerant, comprising the steps of:

preparing a solvent consisting of a mixture of materials selected from the terpene hydrocarbon group and the terpene alcohol group;

placing the solvent mixture in the reservoir of a recirculating pump;

connecting an output of said pump to an input of a system to be flushed;

connecting an output of said system to said recirculating pump reservoir;

operating said pump for a predetermined period of time;

circulating the solvent through said system to cleanse said system;

terminating operation of said pump;

draining all the solvent and refrigerant and other materials contained within said system into said reservoir;

blowing air through said system to evaporate any of said solvent remaining in said system.

2. The process as claimed in claim 1 wherein:

said solvent contains a 50;

50 blend of D-limonene and Dipentene.

3. The process as claimed in claim 1 wherein:

said solvent contains 100% Dipentene.

4. The process as claimed in claim 1 wherein:

said solvent contains a 50;

50 blend of D-limonene and terpinolene.

5. The process as claimed in claim 1 wherein:

said solvent contains an 80;

20 blend of Dipentene and acetone.

6. The process as claimed in claim 1 wherein:

said solvent contains a 50;

50 blend of D-limonene and para-cymene.

7. The process as claimed in claim 1 wherein:

said blowing step is followed by;

emptying said reservoir;

and disposing of said solvent and said refrigerant.

8. The process as claimed in claim 7 wherein:

said disposal step is followed by disposal of said solvent and refrigerant flushed from said system into a land fill to facilitate biodegradability of said disposed materials.

9. The process as claimed in claim 1 wherein:

said recirculating pump operates to pump approximately one gallon of solvent through said system per minute.

10. The process as claimed in claim 1 wherein:

said solvent is pumped through said system for a period from 12 to 24 minutes.

11. The process as claimed in claim 1 wherein:

said blowing of air through said system is for a period of three to five minutes.