andrews R18 Series, Техническая документация инструкция

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18IP22B
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5.4 Water temperature For hot water for personal purposes one can generally take a
When this water is used for other purposes and where there
5.5 Demand for hot water In general the demand for hot water in sanitary hot water instal-
for sanitary use lations is not constant. For example, in a hotel for baths and
Where there is a risk of the water pressure falling below the
minimum pressure a minimum pressure switch should be
included which turns off the water heater.
Under certain conditions and following a high demand it is
possible for the water heater to condensate. It is necessary to
maintain the water heater above the minimum
condensation
point of 36 ° C. To achieve this, a slow operating motorised
valve controlled by a thermostat in the secondary return is
required.
temperature of 43 °C.
are temperature losses in the pipework a temperature of 60 °C
is considered suitable.
Installations supplying large kitchens demand much higher
temperatures. For degreasing a temperature of 65 °C is re-
quired, for sterilising 85 °C. In this case the hot water supply
unit will be operating at a temperature of 85 °C and for sanitary
purposes tempered down to the required levels using thermo-
static mixing valves. (See fig. 22)
showers the highest demand will be in the morning and early
evening.
To determine the output of the water heater, it is therefore
necessary to know the volume and temperature of the water
during these peaks.
The following tables serve as a guide. They are derived from
various sources and from extensive experience.