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Design Procedure
2. Using the pump curve located below, ensure that the System Pump of the X – Pump Block will provide adequate head and flow for
the system in which it is to be installed. If flow rate is unknown, then use Equation No. 1 below to determine required flow.
3. Using the pump curve located below, ensure that the Heat Source Pump of the X – Pump Block will provide adequate head and flow
for the system in which it is to be installed. If flow rate is unknown, then use Equation No. 1 below to determine required flow.
4. Use Equation No. 1 to verify flow rates. Example: 25000 BTU
radiant load with supply temperature of 100
°
and return
temperature of 90
°
.
Application
PUMP CURVES
The Taco X – Pump Block (XPB) is a complete mixing system with an attached heat exchanger for system isolation. Integral to the unit
is a variable speed heat source circulator, constant speed system circulator, heat exchanger, and the electronics to drive it all. With
only four piping connections needed, the XPB greatly reduces the time and space required for installation. The heat exchanger
provides complete isolation between fluid on the heat source side and the fluid on the system side. The XPB can be set up to operate
as an outdoor reset control, a setpoint control or a delta T limiting control, creating flexibility never seen before in a single unit.
Ensure that the contents of this package are complete. If any of the contents are missing or damaged, please contact your local Taco
sales representative for assistance.
Getting Ready
FLOW (gpm)
0
2
4
6
8
10
12
H
E
A
D
(ft)
0
2
4
6
8
10
12
14
16
18
20
SYSTEM SIDE
HEAT SOURCE SIDE
1
2
1
2
Contents should include the following:
•
One X – Pump Block, preassembled
unit consists of the following parts:
- One Variable Speed Mixing Control (VSMC)
- One Green Enclosure
- Two Casings with Circulators Attached
- One Heat Exchanger
- One Power Cord (6 feet)
•
One Taco Outdoor Sensor
•
Two Taco Strap-on Sensors
•
One Instruction Sheet
Flow Rate (GPM) =
BTU's
500 x delta T
EQUATION NO. 1:
= 5 GPM
25,000
500 (100 - 90)
EXAMPLE:
1. Verify BTU capacity of X-Pump Block using charts below.
X-Pump BTU Capacities*
System
Temp.
Heat Source Temperature Range
120/100 130/110 140/120 150/130 160/140 170/150 180/160
70/80
29,900 29,900 29,900 29,900 29,900 29,900 29,900
80/90
29,800 29,800 29,800 29,800 29,800 29,800 29,800
1
90/100 29,800 29,800 29,800 29,800 29,800 29,800 29,800
100/110
4,500 29,700 29,700 29,700 29,700 29,700 29,700
110/120
5,500 29,600 29,600 29,600 29,600 29,600
120/130
6,000 29,600 29,600 29,600 29,600
130/140
6,500 29,500 29,500 29,500
140/150
7,000 29,400 29,400
150/160
7,500 29,300
* Assuming 6 gpm Flow on Radiant Side of XPB
BTU/H Capacity @ 10 degree Delta T Across System
X-Pump BTU Capacities*
System
Temp.
Heat Source Temperature Range
120/100 130/110 140/120 150/130 160/140 170/150 180/160
60/80
59,900 59,900 59,900 59,900 59,900 59,900 59,900
70/90
59,800 59,800 59,800 59,800 59,800 59,800 59,800
1
80/100 27,000 59,800 59,800 59,800 59,800 59,800 59,800
1
90/110
4,500 29,000 59,700 59,700 59,700 59,700 59,700
100/120
5,500 31,500 59,600 59,600 59,600 59,600
110/130
6,000 33,500 59,600 59,600 59,600
120/140
6,500 35,500 59,500 59,500
130/150
7,000 37,600 59,400
140/160
7,500 39,700
BTU/H Capacity @ 20 degree Delta T Across System