Specifications

Catalog 1114-1 SmartSource 2-Stage Water Source Heat Pumps Page 35 of 76
Applications
of the two-pump options using either a UP 26-99F or UP
26-116F piped in series. Pumps piped in series provide ap-
proximately double the head capability compared to single
pump systems. Also see "Loop Pump Performance" pump
curves on page 52.
Figure21:DualGrundfosUP26Pumps-HeatPumps
(sideview)
Water out
Water in
Ball
Valve
Ball
Valve
Pump
2
Pump
1
Ball
Valve
Ball
Valve
Water out to
geothermal loop
Water in from
geothermal loop
Pump Module
Check
Valve
Figure22:SingleGrundfosUP26-HeatPump(side
view)
Water out
Water in
Pump
1
Water out to
geothermal loop
Water in from
geothermal loop
Pump Module
Ball
Valve
Ball
Valve
Ball
Valve
When selecting an appropriate SmartSource loop pump, the
working uid (water plus antifreeze), total head loss and
ow must be known. The following represents the typical
total head loss calculation for a decentralized geothermal
loop pump application:
■ Using nominal 2-ton vertical unit W.GTV.1.026
■ Fluid – 15% Methanol Solution in Water
■ Design EWT Heating - 35°F
(Maximum pressure drop occurs with high density uid. As
a result, the design heating EWT will be used to calculate
the Total Head Loss)
■ Design Water Flow – 3 gpm/ton or 6 gpm for a 2-ton unit
■ Length of 1" HDPE piping between the unit and the
loop eld manifold – 40 feet of length
■ Geothermal Loop – (1) 1" HDPE U-tube - 300 feet bore
depth
Component Head Loss (Ft. of W.C.)
1" HDPE Piping and Elbows 2.3
Geothermal Loop Piping 8.6
Unit – W.GTV.1.026 5.5
Total 16.4
For the design conditions of 6 gpm and a total head loss
of 16.4 Ft., select the UP 26-99F, single pump option. The
system curve and pump curve for this selection is shown
in Figure 23. As a result, the actual calculated ow will be
7.56 gpm with a head on the pump of 28 Ft. Applications
with higher head loss may require the UP 26-116F or one
Figure23:System&pumpcurveforUP26-99Fsinglepumpoption