Hydronic balancing with diferential preassure controllers
Poradnik opisujący zasady równoważenia hydraulicznego za pomocą zaworów róznicy ciśnień.
Tytuł: HYDRONIC BALANCING WITH DIFFERENTIAL PRESSURE CONTROLLERS
Autor: Tour & Andersson
Język: angielski
Format: Adobe Acrobat Document (.pdf)
Wielkość pliku: 399 KB
Spis treści: - 1. Introduction
- 2. Types of distribution systems - advantages and disadvantages 2.1 Variable flow 2.2 Constant flow
- 3. Why differential pressure controllers are useful 3.1 Ensure accurate and stable modulating control 3.1.1 The control loop 3.1.1.1 Elements of a control loop 3.1.1.2 Proportional control 3.1.1.3 Control valve characteristic 3.1.1.4 Control valve authority 3.1.1.5 Sizing a two-way control valve 3.1.2 Behaviour of a variable flow distribution-Plant example 3.1.2.1 Plant at design condition 3.1.2.2 What happens when the control valve of terminal "A" closes? 3.1.2.3 Total average flow of 50% (80% of design load) 3.1.2.4 The use of variable speed pumps 3.1.2.5 The use of local Δp controllers 3.1.2.6 Comparison of results and conclusions 3.2 Minimise noise from control valves 3.2.1 Some types of noise 3.2.2 What can be done? 3.3 Simplify balancing, commissioning and maintenance 3.4 Benefits of differential pressure control and summary
- 4. Applications of the STAP 4.1 How it works 4.2 Air conditioning 4.2.1 One STAP on each riser 4.2.2 One STAP on each branch 4.2.3 One STAP on each control valve 4.3 Radiator heating 4.3.1 Presettable radiator valves 4.3.2 Non-presettable radiator valves 4.4 STAP as a flow controller
- 5. Appendices 5.1 Some questions and answers 5.1.1 Why hydronic balancing? 5.1.2 What are the costs of discomfort? 5.1.3 Is a well-designed plant automatically balanced? 5.1.4 Is a variable speed pump sufficient to obtain the correct design flows? 5.1.5 Is the plant automatically balanced if the two-way control valves are well sized? 5.1.6 Do balancing devices increase pumping costs? 5.2 Minimum flow in a variable flow distribution system 5.3 Different ways of controlling a variable speed pump 5.4 Pumping costs compared with the costs of discomfort
