HEATING | PITRVS pressure options available to suit a range of system set-ups (from 60kPa up to 150kPa, depending on the manufacturer). Standard practice The time-saving benefits and efficacy of PITRVs are boosting demand for the products, says Milner. Specifiers are appreciating shorter system servicing because the automatic balancing negates regular manual balancing, he adds. PITRVs may not be appropriate for some types of heating system; Milner explains that systems with a small flow/return temperature difference such as heat pump circuit that typically require 5K are likely to require a valve to be selected with a higher Kv [flow coefficient] heat pumps require a minimum flow to maintain good performance. However, some PITRVs are available with higher flow rates. (Kv is the flowrate of fluid (m3h-1) through the valve when the pressure drop across the valve is 1 bar (100kPa) the strange units being so that it numerically matches the imperial Cv). Milner notes the importance of correct set-up and maintenance to optimise PITRV-equipped heating systems. Before commissioning, the system should be cleaned and flushed of debris, and treated with corrosion inhibitor to ensure the PH levels are correct and to prevent corrosion. The smaller flow apertures of PITRVs mean system cleanliness is more important, he adds. While the valves usually have a commissioning position for filling and draining during set-up, special consideration is required for power flushing. Power flushing must take place with the valves or valve inserts removed, or before fitting them. A special tool is available on some manufacturers valves to aid power flushing by temporarily removing the valve insert. Milner believes PITRVs will soon become a standard option for domestic Danfoss Dynamic Valve fitted to a radiator heating systems when installers begin to understand that the extra cost of the valves is saved many times over by the ease of installation and time saved during commissioning. Elimination of cold spots around properties and system noise will also reduce the level of call-backs for engineers. Importantly, stricter rules on energy efficiency are likely to feed back into Building Regulations and encourage more energy efficient valve specification in future. CJ 1500 PICV dynamic balancing valve with great efficiency Pegler ProFlow measuring with high accuracy direct measuring fixed venturi orifice accuracy between 2% - 6% NEW The new 1500 PICV is a great addition to the PICV family, with a range flexibility of DN15 to DN50. Complete with direct fast flush cap for access to removing the cartridge. Direct flow measuring utilises the built-in venturi technology. stable flow and measuring can be installed directly onto bends accurate setting optimal flow, according to requirements visible settings customer service +44 (0) 800 156 0010 www.aalberts-ips.co.uk 58 October 2023 www.cibsejournal.com