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4. Use the tekmar control to enable the Primary and Sec-
ondary pumps P2 and P3 relays, and allow remaining
air to circulate through to vents. See previous page for
menu use details.
5. Allow pumps to run until air has been vented. Do not
turn off water supply.
6. Turn off pumps and ensure system is filled to 15 psi.
7. Close valve D2 and turn off water supply. Disconnect
supply hose.
8. Manually enable pumps P2 and P3 again, and adjust
valves V10 and V9 to achieve desired flow.
9. Ensure caps are placed tightly on drain valves and
return the valves to open positions.
10. Return M1 valve actuator to position 0 and the mode
selection switch to AUTO.
11. Close valve D1 and turn off water supply. Disconnect
supply hose.
12. Ensure caps are placed tightly on drain valves and
return the valves to open positions.
Fill Primary (boiler) Side
1. Close V9
2. Open V10, V5, V6, V7, V8
3. Attach fill hose to D2 and begin filling
a. Water will push air slugs into main air vent A2
b. Fill until air stops venting from A2 and pressurize to
15 psi
Adjusting System Pressure
Snow melting systems are typically subjected to
temperatures well below freezing. As the anti-freeze
solution decreases in temperature, its volume will also
decrease. This will result in lower system pressure
during the winter months when the system is not
operating.
The minimum required operating pressure for the
ProMelt panel is 5 PSI.
If the pressure falls below
5 PSI, additional anti-freeze solution will need to be
pumped into the system to maintain the minimum
pressure in the coldest conditions. When adding anti-
freeze solution in cold conditions, do not exceed
10 PSI!
System Commissioning and Maintenance
A2
V5
V6
V8
V7
V9
D2
V10
D1
V1
V2
A1
M1
V3
P1
V4
Due to the large temperature swing in the system fluid
(110 degrees F. or more from cold start to full output),
typical operating pressure will range between 5 PSI
(required minimum) to 25 PSI (recommended maximum).
In excessive pressure conditions, the pressure relief
safety valve will begin to open at 30 PSI. If this condition
occurs, contact Watts Radiant technical support for
assistance.