How To Rescue Failing Systems?

Transcription

1 How To Rescue Failing Systems? Stephen Hart Managing Director, Frese UK

2 Frese Group Activity & Focus Markets 2

3 Frese UK Marine & Industrial Thermal Interface Units (HIUs) Frese UK HVAC Frese Valves Frese District Heating Integrated Hydronics 3

4 Frese District Heating Turnkey Projects Heat Network Recovery 4

5 Practical Solutions To Common Problems

6 Where Are The Common Problems? Energy Centre Heat Network Apartment Connections System designed to collect R.H.I. and NOT on sound engineering principles Apartment Heating System Ownership Ownership Ownership Access Maintenance Maintenance Maintenance Excessive bypass flow Water Treatment Insulation Insulation Water Treatment Monitoring & Control Excessive bypass flow Balancing & control Balancing & control System commissioned as separate elements and lack of education for landlord and tenant 6

7 Ownership & Access Plant equipment should be accessible for maintenance but secure to prevent unauthorised access. Control panel design should prevent unauthorised tampering allow for remote monitoring 7

8 Maintenance & Water Treatment Clean on the inside! Functioning on the outside! Take regular water samples Primary, Secondary & Apartment Water treat as necessary Relocate plant equipotent to enable or simplify maintenance 8

9 00:07 00:37 01:07 01:37 02:07 02:37 03:07 03:37 04:07 04:37 05:07 05:37 06:07 06:37 07:07 07:37 08:07 08:37 09:07 09:37 10:07 10:37 11:07 11:37 12:07 12:37 13:07 13:37 14:07 14:37 15:07 15:37 16:07 16:37 17:07 17:37 18:07 18:37 19:07 19:37 20:07 20:37 21:07 21:37 22:07 22:37 23:07 23:37 The Root Problem: Low Delta T 78 Primary Flow & Return Thursday 22/09/ Flow Return 9

10 The Cost of Low Delta T 10 Yearly demand for district heating in a one family house Delta T: 40 C 21,500 l/year Delta T: 30 C 28,667 l/year Delta T: 20 C 43,000 l/year Delta T: 10 C 86,000 l/year 10

11 Reduce Flow Through Heat Emitters 11

12 Temperature Controlled Bypasses 12

13 Pump Speed Control 13

14 Disable Keep Warm Function

15 A Well Designed Heat Network (C) (E) (H) (J) (A) (D) (F) (G) (I) (C) (B) (K) (C) A. Thermal store to minimise use of peak boiler and maximise use of renewable heat source B. Pressure independent control to provide weather compensated secondary flow temperature C. Variable speed pumps with a range of duties to suit demand D. Temperature controlled bypass at extremities of network E. Pressure Independent control valve to ensure variable flow in DH network and to maximise ΔT at all conditions F. Heat meter to encourage careful use of energy G. Plate heat exchangers sized for low return temperatures (often in the form of a packaged heat interface unit) H. Control valve to maintain low return temperature with balancing facility to limit flow rate and return temperature I. Heat emitters sized to give low return temperature J. Room thermostat and time clock K. DH Surveillance system for remote monitoring of network 15

16 How To Rescue Failing Systems? Stephen Hart Managing Director, Frese UK