This module builds on the material covered in Introduction of Building Services Engineering & Building Services Consolidations in the first year of the programme. It examines the key components of Low Pressure Hot Water (LPHW) Heating Systems, with emphasis on how to select plant and design primary and secondary distribution circuits and controls to provide acceptable indoor comfort conditions while minimising energy consumption. This subject introduces the student to the engineering design of LPHW systems in buildings. It encompasses the design, installation and regulatory requirements of LPHW systems including modern renewable technology features
PUMP SIZING: Revision of LPHW pipe sizing, fittings velocity pressure coefficients and use of zeta tables, Calculation of LPHW pump duties and application of appropriate design margins.
TYPICAL LPHW HYDRAULIC PIPEWORK ARRANGEMENTS: Common boiler primary circuit arrangements and safety features for conventional, condensing and Biomass boilers arrangements, Secondary circuit arrangements, Low loss headers, pump, pressurisation unit, commissioning piping arrangements, condensing boiler and air source heat pump (ASHP) piping arrangements & integration of heat pumps in commercial heating systems (Monovalent & Bivalent) and the use & sizing of buffer vessels.
PUMP ENGINEERING: Pump laws, pump and system characteristic curves including plotting, actual and final operating points when pump(s) are connected to a system, series and parallel pumping arrangements and analysis, constant versus variable pumping analysis and energy saving potential, common variable speed pumping arrangements and control, two-port and 3-port control of emitters.
LPHW SYSTEM PRESSURISATION: Feed & expansion tank requirements on open systems, sealed systems, System water expansion, effects of static head, acceptance volume, Sizing and selection of expansion vessels, pressurisation using air.
LPHW BOILERS/ASHP’s: Conventional oil/gas fired boilers, condensing boilers principles and application, ASHP principles and application, system efficiencies, compact/split ASHP installations, and boiler house ventilation requirements.
SIZING & SELECTION OF ASHP’s: Heat pump performance parameters, heat pump efficiency terminology, the defrost cycle, Selection of appropriate flow temperatures, suitable ASHP refrigerants, ASHP performance data & analysis, establishment of the bivalence point, ,sizing and selection of heat pumps.
This module will be delivered as a series of lectures, discussions and class based problem-solving exercises.
| Module Content & Assessment | |
|---|---|
| Assessment Breakdown | % |
| Formal Examination | 80 |
| Other Assessment(s) | 20 |