Hot water heating yesterday...

1. Hot water heatingyesterday... 1877

2. Hot water heating … and today • Principle • Heating system • Heat source • Distribution network • Heat emitter • Heat transfer medium • water • steam • air

3. Hot-water heating • Terminology Radiator valve Branch supply/return pipe Radiator Radiator Vent cock Manual Control valve Main supply/return pipe Shutoff valves Boiler Expansion tank Drain/feed cock

4. Heating system designInitial information about the building • Type • industrial, office, dwelling • Operation • continuous, intermittent • single, multiple • Structure • heavy, light • new, reconstruction

5. Heating system design Functional requirements • Connection of the heat emitters with the heat source • Deaeration • Draining • Integration into the building

6. Heating system design Optimisation criterions • Length of the pipes • Location of the heat emmiters • Control of the system • Investment costs • Operational costs • Maintenance

7. Design parameters of hot water heating systems • (1) Water circulation • (2) Geometry of the system • (3) Water temperature • (4) Expansion vessel • (5) Materials

8. P1 P2 Water circulation • Natural – without pump P1=h.ρ1.g P2=h.ρ2.g ΔPn=P2-P1=h.(ρ2- ρ1).g • Forced – with pump ΔPF=ΔPn + ΔPP

9. Geometry of the system • Relative connection of the heat emitters • One-pipe, two-pipe • Main pipe lay-out • Upper, lower, combined • Branch pipes lay-out • vertical, horizontal , microbore

10. Geometry of the system Relative connection of the heat emitters • Relative connection of the heat emitters • Two-pipe system • One-pipe system

11. Two-pipe systems • Contraflow, parallel flow Tichelmann

12. One-pipe systems Basic schemes of the connection • Serial • With By-Pass • “Horse Rider“ • Controlled by-pass • With mixing valve • Two-point • One-point

13. One-pipe systems Mixing valves Two-point valves One-point valves Ventil compact

14. On-pipe systemsHorse -rider Low pressure radiator valves

15. Relative connection of the heat emittersConclusion Two-pipe X one-pipe system • Length of the pipes • Water circulation • Measuring and control • Pressures in the system

16. Geometry of the systemMain-pipe layout Lower Upper Combined

17. Branch pipes lay-out Vertical Horizontal Hvězdicová Microbore