Troubleshooting: Cemline Steam Fired Water Heater – Cemtrol Controller

In this Service Tip of the Month, R.L. Deppmann we will show you the components of an installed Cemline Steam Fired Water Heater unit with Cemtrol Controller. We’ll also show you some helpful troubleshooting tips.

This image is the display showing your desired set point, your actual temperature, and the voltage going to the control valve/actuator.

Steam traps are located off of the steam bundle and also on the drip leg that supplies steam to the control valve. The vacuum breaker is located on the pig tail coming off of the steam bundle. It is important to not put a plug in this and should remain open. The purpose of the vacuum breaker is when the steam valve closes, the steam is condensing in the bundle, creating a vacuum and then a vacuum breaker opens allowing the bundle to reach atmospheric pressure. Thus, allowing the condensate to fully drain.

This is the secondary high limit, when secondary high limit is reached the solenoid valve opens and dumps to drain, allowing cold water to enter the unit and cool it down.

The below image shows the primary and secondary temperature sensors. These are wired back to the controller.

This image displays the primary high limit set point, when reached it disables and closes the control valve/actuator. This set point is typically set 10-15 degrees higher than your actual set point.

This image shows the secondary high limit set point, when reached it opens the solenoid dump valve. This set point is typically 15-20 degrees Fahrenheit higher than your actual set point.

This is the pump that is circulating through the unit to maintain a constant temperature across the bundle.

This image shows a good example of a gravity fed condensate return line off of both steam traps from the water heater. The unit must be piped this way to avoid damage to the bundle by backing up condensate.

Troubleshooting Tips

Most common symptoms of a Cemline Steam Fired Water Heater:

1. SYMPTOM: If you’re hearing loud banging in the water heater, primary piping, or condensate/water return piping (not to be confused with a normal clicking noise made during operation).

WHY…

• The condensate or water return piping may not be installed properly. This piping should drain freely by gravity.
• The primary steam line may not be properly trapped.
• The condensate/water check valve is leaking or has failed

2. SYMPTOM: Outlet temperature is too high.

WHY…

• Circulating pump is not moving water through the recirculation line and through the unit.
• The condensate or water return piping may not be installed properly. This piping should drain freely by gravity.
• The control valve may not be closing properly.

3. SYMPTOM: Pressure relief valve “pops.”

WHY…

• The control valve may not be closing properly.
• The over-temperature limit system is out of adjustment, or some component of the system has failed.
• The secondary/outlet energy source pressure control system is not operating properly.

For more information on Cemline products, contact an R. L. Deppmann representative to learn how we can help!