Technical data

www.dimplex.de 01.2012 | Project planning manual for heat pumps for heating and domestic hot water preparation | 41
Brine-to-water heat pump 3.2.6
3.2.6 Standard dimensioning of ground heat collectors.
The data in the dimensioning table Table 3.5 on page 42 are
based on the following assumptions:
 PE pipe (brine circuit): Pipe DIN 8074
32 x 2.9 mm – PE 100 (PN 12.5)
 PE feeder pipe between the heat pump and the brine circuit
according to DIN 8074:
 Nominal pressure PN 12.5 (12.5 bar)
 Specific abstraction capacity of the ground approx. 25 W/m
2
for 0.8 m clearance
 Brine concentration: minimum 25% to maximum 30% anti-
freeze (glycol-based)
 Pressure expansion vessel: 0.5 bar primary pressure
NOTE
With the Dimplex operating cost calculator, a ground heat collector for
brine-to-water heat pumps can now be configured for every region in Ger-
many.
The latest version of the operating cost calculator and further information
on this topic can be found at
www.dimplex.de/online-planer/wp-rechner.
NOTE
The design of the brine circulating pumps is only valid for section lengths
up to a maximum of 100 m and the given number of brine circuits!
An increase in the number of brine circuits and a reduction in the
section lengths does not have a critical effect on the pressure
drops if all other parameters remain unchanged. For varying
framework conditions (e.g. the specific abstraction capacity,
brine concentration), the total permissible pipe length for the flow
and return between the heat pump and the brine circuit manifold
must be dimensioned again.
The quantity of antifreeze listed in Table 3.2 on page 36 is
based on the given wall thicknesses. The amount of antifreeze
should be increased for smaller wall thicknesses in order to
maintain the minimum brine concentration of 25%.
Heat pump
Circulating pump
same type of model or similar
Circulating pump
Alternative
Minimum brine flow rate
Refrigeration capacity
Pipe length ground collector
1
1. according to Chapt. 3.2.6 on page 41
Number of brine circuits
Pressure expansion vessel
Permissible total pipe lengths for flow and
return between the heat pump and brine
circuit manifold
Motor protection
32 x 2.9 40 x 3.7 50 x 4.6 63 x 5.7 75 x 6.8 90 x 8.2
110 x 10
125 x 11.4 140 x 12.7
m
3
/h kW m l m m m m m m m m m A
SI 5ME Wilo TOP-S 25/7.5 UPS 25-60 1.2 3.7 200 2 8 50
2
2. With integrated full motor protection or blocking current-resistant motor
SI 7ME /
SIH 6ME
Wilo TOP-S 25/7.5 UPS 25-60 1.7 4.7 300 3 8 15 40 110
2
SI 9ME /
SIH 9ME
Wilo TOP-S 25/7.5 UPS 25-80 2.3 6.9 400 4 12 20 65
2
SIK 11ME Wilo TOP-S 25/7.5 UPS 25-80 3 9.1 500 5 12 10 70
2
SI 11ME /
SIH 11ME
Wilo TOP-S 25/7.5 UPS 25-80 3 8.3 500 5 12 10 70
2
SI 14ME Wilo TOP-S 25/7.5 UPS 25-80 3.5 10.9 600 6 18 20 70
2
SIK 16ME Wilo TOP-S 25/7.5 UPS 25-80 3.5 11.3 700 7 18 20 70
2