Ohio residential appliance installer license prep class instal the new version for ios

An example would be a hot water space-heating boiler operating under 15-20 pounds of pressure coinciding with a reduction of the city water supply below this pressure (or higher in most commercial boilers). What factors can cause a back pressure-backflow condition?īack pressure-backflow is created whenever the downstream pressure exceeds the supply pressure, which is possible in installations such as heating systems, elevated tanks, and pressure-producing systems.

The effect is similar to the sipping of an ice cream soda by inhaling through a straw, which induces a flow in the opposite direction. What factors can cause back-siphonage?īack-siphonage can be created when there is stoppage of the water supply due to nearby fire-fighting, repairs or breaks in city main, etc. What is back-siphonage?īack-siphonage is the reversal of normal flow in a system caused by a negative pressure (vacuum or partial vacuum) in the supply piping. Backflow is the reverse flow of water caused by a loss of pressure in the system or connections to the system that have a higher pressure than the supply pressure.

Ohio residential appliance installer license prep class instal the new version for ios