Hamworthy UF100-1, Инструкция по установке, вводу в эксплуатацию и эксплуатации

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HAMWORTHY HEATING LTD
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UPTON FLOOR STANDING SERIES 500001340/C
E1.8 Minimum Water Flow Rates
Minimum water flow rates are shown in table at beginning of Appendix E. These flow rates should be maintained
through the boiler at all times whilst the boiler is firing. To prevent the boiler firing in the event of poor or no flow,
the boiler is fitted with an integral flow switch. Particular attention should be paid to the restriction of external flow
circuits during periods of low heat demand.
E1.9 Waterside Pressure Drop
The waterside hydraulic resistance (Pressure drop) is given in table at beginning of Appendix E.
E1.10 Water Flow Controls
Any external mixing valve / shunt pump or similar controls MUST always ensure that the minimum water flow rate
as given in table at beginning of Appendix E is maintained. As a precaution, the Upton boiler is fitted with a flow
switch. The flow switch is designed to operate such that the boiler will shut down if insufficient flow occurs.
E1.11 Frost Protection
Consideration should be given to fitting an optional outside air sensor, to provide the necessary frost protection.
E1.12 Unvented Systems
For system design refer to BS 7074 Part 2. In order to correctly size a pressurisation unit for any heating system
the following parameters are required.
1) Static height of highest component in system (metres)
2) System volume. If this is not known, a general rule of thumb of 10litres/kW of installed boiler power
can be used.
3) Maximum flow temperature (°C)
4) Maximum system hot working pressure, generally given in bar gauge.
From the parameters given, Hamworthy Heating can size the pressurisation unit and also the expansion vessel.
Care must be taken in sizing expansion vessels to ensure maximum acceptance factors are not exceeded.
Normally manufacturers of vessels impose a limit of 0.5. This value must not be exceeded at any time during the
operation of the boiler, this includes the over pressure condition should a safety valve lift.
Consideration should also be given to sizing of the safety valve(s) in the system.
E 1.13 Minimum System Water Pressure
To comply with guidance note INDG436 (Health and Safety Executive) , the minimum pressure requirements at the
boiler are given below : -
Individual boiler @ 82°C ......................................................................................................... 0.5 bar
Multiple boilers
With flow isolation (pump or valve) @ 82°C ............................................................................ 0.5 bar
Without flow isolation @ 20°C rise across the system @ 82°C ............................................ 1.0 bar
Please note that the maximum flow temperature available from the controls is 85°C
E1.14 Pressure Limiter
Each boiler is fitted with a pressure limiter to shutdown the boiler if the pressure exceeds the maximum or
minimum operating limits.