The presence of escaping gas during the process of preparing a backflow prevention device for cold weather conditions indicates a critical step in ensuring its protection against freezing. This expulsion is typically observed when the device is drained of water and pressurized with forced gas, commonly through an air compressor. The exiting substance confirms that water has been effectively displaced from the internal components of the backflow preventer, such as check valves and relief valves. As an example, visible bubbles emanating from test cocks or open ports of the device as air is introduced signal successful draining.
Properly removing water from a backflow preventer is paramount in preventing damage caused by expanding ice during freezing temperatures. Neglecting this procedure can lead to cracked housings, broken internal parts, and ultimately, a compromised backflow prevention system. The action of verifying complete water removal through the observation of displaced air provides a degree of confidence that the device will withstand the winter without sustaining damage. This process saves on repair costs and ensures uninterrupted water supply when warmer temperatures return. Historically, failures in backflow prevention devices due to freezing have highlighted the necessity of effective draining and air purging methods.
