Hamworthy Warmwell 120, Инструкция по установке, наладке и обслуживанию

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HAMWORTHY HEATING LTD WARMWELL 500001091/F
Figure 3.3 Balancing of Mixed Boiler Systems
Warmwell Boiler Purewell Boiler(s) Balancing Valves
LOAD
System Pump
Reverse return header system
Position of
shunt pump
(if required)
It should be noted however, that even if the boiler
water were of average hardness, not requiring
treatment, subsequent draining of the system for
repair or constant make-up water due to an
undetected leak would cause additional deposits
and gradual build-up of scale. It is essential
therefore, those leaks are attended to promptly and
draining is kept to an absolute minimum.
It is recommended that the system be flushed out at
least twice before any water treatment is added. If
any doubt exists regarding the internal cleanliness
of an old system, consideration should be given to
the fitting of a coarse filter in the return pipework to
the boilers.
3.3 Adequate Water Flow
The Hamworthy Warmwell boiler is designed as a
quick response, low water content unit, to run
continuously with maximum reliability. Care should
be taken in the initial design and layout having due
regard for adequate water flow through the boilers
and the influence of the system controls.
The Warmwell boiler is tested with flow/return
temperatures of 50/30°C to ensure condensing
takes place thus achieving the correct output. The
boiler can also be used in the high efficiency mode
with flow/return temperatures of 80/60°C, i.e. non-
condensing where it will provide the lower heat
output as given in Figure 2.2 (p4).
If the temperature/flow rates of the application
cannot meet those given in Figure 2.2 (p4), it may
be necessary to incorporate mixing valves and
shunt pumps to ensure that the boiler will operate
satisfactorily. See Figure 3.3.
The pressure loss though the Warmwell boiler is
generally higher than the equivalent Purewell unit. It
therefore may be necessary to incorporate
balancing valves where these units are mixed on the
same header. See Figure 3.3.
Figure 2.2 (p4) shows recommended and minimum
water flows required. The control system and
valves, where fitted, should be regulated to avoid
lower flows occurring. The flow corresponding to
22°C temperature rise across the boiler is the
minimum recommended at any time. For boiler
pressure drop see Figure 2.2 (p4).
3.4 Time Clock Control
In order to avoid local overheating and progressive
calcium deposition at zero flow conditions where
boilers are operated from time clocks, provision
should be made for a 5 minute circulating pump
over-run after the last boiler has ceased firing.
NOTE!
Time clocks should not interrupt live, neutral
or earth connections, see Section 9.0:
ELECTRICAL SUPPLY (p13) for details. See
Figure 9.1 (p15) for wiring details.
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