HEATING SYSTEMS | LOW LOSS HEADERS It is important to maintain water quality for the life of a system to maintain the low-loss properties of a header over time on the likely increase in pipe pressure losses over time. For the example calculation, while a header using new steel pipe will have a pressure loss of 3.65Pa.m-1, a corroded pipe will have 5.26Pa.m-1, and a badly corroded pipe 11.78Pa.m-1. It is important to maintain water quality for the life of a system to maintain the low loss properties of a header over time. Recommended system configuration of a type 2 header effectively eliminates greater than the static pressure difference will not occur. circuits by a type 1 header when off-load few hundred Pa at most. However, when on-load, a type 1 header does not provide hydraulic separation, as the primary has the potential to pump into the secondary and then back into the primary. Installing non-return valves (NRVs) in series with each secondary pump has providing the pressure required to open the NRVs is greater than the pressure imposed by the header across the load circuits. CJ the form of a non-peer-reviewed research tool, can be downloaded from the CIBSE Journal site at bit.ly/LLHcalc on injection plumes, the striking pressure and comments on the calculator, is asked to post header) to editor@cibsejournal.com RYAN KIRKWOOD is the heat pump business development manager for Baxi Heating DAVID PALMER is now retired. He was formerly a director of the Campbell Palmer Partnership 54 May 2021 www.cibsejournal.com CIBSE May 21 pp52-54 Low loss headers Supp.indd 54 23/04/2021 18:07