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Aquarea air / water heat pump – design handbook 07 / 2014
Project Design
Panasonic Aquarea Designer | Establishing the heating load and
outside design temperature
View of the Start user interface of the Panasonic Aquarea Designer for calculation
and optimisation of heat pump heating systems
5.3 Establishing the heating load and outside design temperature
The heating load of a building is determined according to EN 12831
“Method for calculation of the design heat load”. For new buildings design
heat loads are derived from the planning documents. The heating load is
calculated assuming an outside design temperature
θ
e. This value can
be derived from CIBSE Guide A: ‘Environmental Design’, table 2.4. In
the UK, this typically varies beween -1 ˚C and - 5 ˚C at sea level. This
temperature is equal to or is exceeded for 99 % of the hours in a year.
A selection is reproduced in the table below. Please note: If using the
closest location to your site in the table, you must decrease the tempera-
ture by 0.6 ˚C for every additional 100 metres above sea level.
Location
Altitude (metres)
Temperature (˚C)
Belfast
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-1 .2
Birmingham
96
-3 .4
Cardiff
67
-1 .6
Edinburgh
35
-3 .4
Glasgow
5
-3 .9
London
25
-1 .8
Manchester
75
-2 .2
Plymouth
27
-1 .2
Determination of standard outside temperature θe according to CIBSE Guide A:
Environmental Design