WaterFurnace Envision Hydronic (NSW) - Manual (Page 26)

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NSW INSTALLATION MANUAL
Converting to a Dedicated Cooling Unit
Procedure to Convert a Heating Only Unit to a
Cooling Only Unit
All non-reversible NSW units are built at the factory as
dedicated heating units. Follow the procedures below to
make the unit a dedicated cooling unit.
1. Shut off all power to the unit.
2. Remove the top and access panel.
3. Remove the brass in-well thermistor from the load
water-in line.
4. Remove the brass plug from the source water-in line.
5. Place new Teflon ® tape on the threads of the brass in-
well thermistor.
6. Thread the brass in-well thermistor into the source
water-in line.
7. Make sure the thermistor wires do not touch the
discharge line.
8. Place new Teflon ® tape on the threads of the brass plug.
9. Thread the brass plug into the load water-in line.
10. Refer to the labels on the unit for the location of ports
and lines.
11. Connect the “Source Water-In” line to the port marked
“Load Water-In.” Then, connect the “Source Water-Out”
line to the port marked “Load Water-Out.”
12. Connect the “Load Water-In” line to the port marked
“Source Water-In.” Then, connect the “Load Water-Out”
line to the port marked “Source Water-Out.”
Control Board with Jumper
P4
P5 Key Pad
(Interface)
P9
Not Used
P2
P1
13. Open the control box.
14. Find the connection marked “P4” as shown in the
Control Board with Jumper illustration.
15. Move the “P4” jumper from across 1 and 2 to across 2
and 3.
16. Close the control box and secure the screws.
17. Replace the top and access panel.
18. Make sure all screws have been re-installed.
19. Turn on the power.
20. Using the touch-pad, press the UP arrow.
21. The displays should blink “44” to show set point. Now,
the unit should operate as a cooling only unit.
Jumper Pin Location
The location of the jumper pin determines the controller’s
mode of operation. Move the jumper pins to the correct
location for dedicated heating, dedicated cooling or
reversible settings as indicated below.
Dedicated heating - 1 & 2 *
Dedicated cooling - 2 & 3
Reversible - 3 & 4 *
* Indicates factory setting.
NOTE: A reversible unit can not be configured to heating only.