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TH-750-IMI-REV-
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Section 2 – Startup Procedure and Operation
1. Verify that all manual valves are closed on the water and heat (steam) sources.
2. Locate the black circulation pump On-Off switch (on side of EC800 panel) and make sure
that it is in the OFF position.
Failure to turn the recirculation pump off will run the pump
dry causing failure.
3. Power up the panel. This will close the high temp drain solenoid valve and activate the
temperature controller.
This valve is a normally closed valve.
4. Slowly open the water supply valve to the shell of the TH-750 and allow the shell to fill with
water (checking for leaks). Repair any leaks before proceeding with startup.
5. Open valves on the recirculation loop and when shell is full of water turn the recirculation
pump ON.
6. With a small user turned on and calling for hot water (sink hot water faucet or shower), slowly
open the hot water outlet valve. This will allow the shell to completely fill with water and
remove any air from the shell.
Never use the Pressure & Temperature relief valve to
remove air.
7. The digital controller will sequence for a few minutes following initial power up and then
return to its operation mode. The controller has been preset at the factory before shipment
and should not require adjustment.
8. Two numbers will appear on the front of the controller. The lower number is the outlet water
temperature set point. The upper number is the actual water temperature in the shell.
9. For TH-750 units with
pneumatic control
, ensure that the instrument air supply is
connected and open to the panel.
10. The EC800 panel for pneumatic control includes a pressure gauge. This gauge indicates the
air pressure to modulate the control valve.
11. When the system is first turned on, the water in the shell will be cold and controller will be
sending out its maximum air signal to the control valve which will register 15 to 30 psig on the
gauge.
12. As the system nears set point, the pressure will begin to drop until the gauge finally reads
zero when set point temperature has been achieved.
13. As the system functions normally, the pressure reading on the gauge will rise and fall,
modulating the steam valve.
