"Boiler Acid # B.L. 807

Davies “Boiler Acid # B.L. 807” is a complex blend of special acids and acid activators, compounded to dissolve tenacious silica scale. “Boiler Acid # B.L. 70” is ideal for the vast majority of boiler scale problems, but is ineffective against silica scale. “Boiler Acid # B.L. 807” is effective on all types of boiler scale. The customer may know, or a simple lab test will determine the presence of silica in boiler scale.


Before adding acid to boiler, the stream line should be shut off either by valve or disconnecting line to prevent acid from going into steam line. Hook up circulating pump for circulating  acid water in boiler. The pump should be a pump made to withstand acid. A pH of 1 to 2 must be maintained in boiler to obtain optimum results. The amount of boiler acid needed will vary depending on water conditions and the type of scale built up in boiler. As a starting point, add 5 gallons of  DAVIES “Boiler Acid # B.L. 807” to each 100 gallons of water in boiler. Various makes and models of boilers will vary as to amount of water in boiler. Various makes and models of boilers will vary as to amount of water they hold. The following chart may be used as an approximate starting point and to adjust acid content using pH test as a final guide.  

15 H.P. 180 Gal. Water

100 H.P. 715 Gal.  Water

25 H.P. 235 Gal. Water

150 H.P 1115 Gal. Water

50 H.P. 290 Gal. Water

200 H.P. 1335 Gal. Water

After acid has been added to boiler water and adjusted to read pH of 1 or 2, start circulating pump and heat water to a temperature of 190° to 200° F. Check pH each 30 minutes and add more acid as the acid dissipates itself dissolving the scale. It is difficult to estimate how much total acid will be needed to acidize a boiler due to the various kinds of scale. Using a starting point of 5 gallons “Boiler Acid # B.L. 807” to each 100 gallons of water and estimate the need of adding 2 gallons every ½ hour per 100 gallons of water for a period of 8 hours would make approximately 21 to 29 gallons acid per 100 gallons water depending on an 8 hour or 12 hour acidizing job.

For badly scaled boilers, it may be necessary to acidize for a period of 8 to 12 hours, depending on degree and type of scale. After the completion of acidizing, drain boiler, clean out all loose scale, and fill again with rinse water. Add to  ‘rinse water’ enough ‘Boiler-Neutro’ to bring pH up to 13. It will take approximately 4 gallons of ‘Boiler Neutro’ per 100 gallons of water. Test water with pH tester and adjust accordingly. Bring rinse water to a temperature of approximately 180° F. Circulate for a period of ½ hour to 1 hour and drain boiler again. Check for more loose scale and clean out. After thorough clean out of all loose scale, close boiler and fill with water and add proper amount ‘No-Scale’. Boiler will be clean and ready for operation.


Protective goggles should be worn to protect eyes in the event of splashing as well as a suitable protective garment to protect the body. Open all windows and maintain adequate ventilation to remove acid fumes.

“Boiler Acid # B.L. 807” is packaged in 5 gallon pails, 15 gallon plastic drums and 55 gallon drums