Backflow Prevention devices for carbonators and industrial chillers

1. Backflow Prevention devices for carbonators and industrial chillers June M. Weintraub, ScD, REHS Environmental Health Branch May 2019 http://www.jpchemtech.in/Boiler-Chemicals.php

2. Carbonator + Copper Pipe = Health Hazard • When CO₂ is mixed with water, carbonic acid (a weak acid) is formed. CO2+ H2O  →  H2CO3 • Many water supply lines are made from copper.If CO₂ backs up into a copper water linecarbonic acid will dissolve some of the copper.  Cu(OH)2 + H2CO3 → 2 H2O + CuCO3 • Copper Carbonate can cause illness – vomiting, nausea, easily mistaken for food poisoning

3. Industrial Chillers Usually Use Chemicals • Industrial chiller and boiler chemicals are widely used to ensure proper functioning and equipment life • Backpressure or backsiphonage conditions can occur, introducing hazardous chemicals into the potable water supply and risk of illness for those who might consume contaminated water • Plumbing Code allows a DC device if a chiller or boiler is not planning to use chemicals • This rarely happens -- even if an installation “thinks” they won’t be using chemicals in their boiler/chiller, there is always the possibility that chemicals will be used at some later point • Therefore it is good practice to protect as though all industrial chillers and boilers are planning to use chemicals and require an RP or air gap

4. Uniform Plumbing Code / CPC Requirements in Table 603.2

5. ASSE 1022 Backflow Preventer Image credit: https://www.andersonbrass.com/back-flow-products