Troubleshooting: Recirculating Pump Is Working But Water Is Not Circulating

A hydronic heating system’s recirculating pump is crucial to ensuring that hot water is circulated uniformly throughout the house. It can be frustrating and inconvenient, though, when the recirculating pump is on but the water is not moving. We will examine the typical reasons for this issue in this post and give you a step-by-step solution manual.

Fundamentals of Hot Water Recirculating Pump

Installing a hot water recirculating pump in a hydronic heating system ensures that hot water is always available at the faucets. The system ensures that hot water is always available on demand by re-circulating water from the water heater to the farthest fixture and back to the heater.

Typically, a return line is run from the farthest fixture in the house or building back to the water heater, where the pump is placed. Hot water is recirculated through the return line after being activated by a timer or temperature sensor.

When turned on, the hot water recirculating pump sends hot water from the water heater all the way to the farthest fixture in the system via the supply line. The pump keeps the hot water circulating through the return line back to the water heater when it is used at different faucets around the house or building. With this system, heated water is constantly being recycled, so it may be used whenever it’s needed.

Both on-demand and conventional pumps can be used for recirculating hot water. When a motion detector or button is pressed, an on-demand pump starts recirculating hot water. The constant recirculation of hot water by conventional pumps, which is triggered by a timer or temperature sensor, might be inefficient.

Common Causes of Recirculating Pumps Not Circulating Water

Many hydronic heating systems depend on recirculating pumps to deliver hot water to radiators or baseboard heaters. However, there are a number of typical reasons why these pumps might fail to circulate water properly, which could result in ineffective heating and possible system damage. These reasons include:

Insufficient Water Level

The lack of an adequate water supply is a common reason why a recirculating pump won’t work. Low water levels can cause the pump to function but not circulate water since there isn’t enough in the system to push it around. Make sure the system has enough water by checking the level and adding more if needed.

Clogged Impeller or Pump

Another cause of a recirculating pump not circulating water is a clogged impeller or pump. Over time, debris and sediment can build up in the pump, causing it to become clogged and preventing water from circulating. To troubleshoot this problem, turn off the pump and inspect the impeller and pump for any blockages. If there is a blockage, clean the impeller and pump thoroughly.

Malfunctioning Motor

When a recirculation pump stops working, one common cause is a broken motor. It is impossible for the pump to move water if the engine is broken. If you suspect the motor is broken, you should verify the pump’s power source and do a continuity test on the motor. Repairing or replacing the motor could be necessary if it is not working properly.

Airlock or Cavitation

It’s possible for the pump to function but not circulate water due to an airlock or cavitation. When water flow is blocked because of trapped air, we say that there is an airlock. But cavitation happens when the pump can’t push water through the system because the pressure is too low. Bleeding the air from the system or increasing the pump pressure is required to resolve this issue.

Blocked or Closed Valves

Blocked or closed valves can also cause a recirculating pump not to circulate water. If the valves are blocked or closed, the water will not be able to flow through the system. To troubleshoot this problem, inspect the valves and ensure they are open and unobstructed.

Troubleshooting a Recirculating Pump That’s Not Circulating Water

Step 1: Turn off the Power Supply –The first thing to do when troubleshooting a recirculating pump that is not pumping water is to disconnect the power to the pump.

Step 2: Inspect the Water Level –The second step is to check the water level to make sure the pump has enough water to circulate. If the water level is low, you should replenish it.

Step 3: Check for Blockages –Examine the Impeller and Pump for Debris If water is not circulating through the system, it may be because of debris or blockages. It’s important to keep the pump and impeller clean.

Step 4: Test the Motor –Check the Motor Make sure the pump has electricity and that the motor has continuity. Repairing or replacing the motor could be necessary if it is not working properly.

Step 5: Bleed the Air from the System –  The fifth step is to bleed the air from the system or boost the pump pressure if there is an airlock or cavitation in the pump.

Step 6: Inspect the Valves –  Check to see that all of the system’s valves are open and unblocked. Turn the water back on by releasing any valves that may be stuck or closed.

Advice on How to Prevent the Issue from Occurring Again

The issue of the pump running but the water not circulating can be avoided with routine maintenance of the recirculating pump and the entire hydronic heating system. Observe the following advice:

• Maintain the recirculating pump on a regular basis by cleaning the impeller, inspecting the motor, and checking the valves.
• Check the water level in the system frequently, and add water as needed.
• To avoid silt buildup in the system, use a water treatment solution.
• To stop the system from being harmed by hard water, use a water softener.

When to Contact a Specialist

While some homeowners may be able to fix a recirculating pump that isn’t moving water, there are some circumstances where professional help is required. Here are some situations where you ought to contact a pro:

• After troubleshooting, the pump is still not circulating water.
• The motor has to be fixed or replaced because it isn’t working properly.
• The system needs to be fixed because there is a leak.
• The current system must be changed because it is antiquated.

Importance of Regular Maintenance

The issue of the pump running but the water not circulating can be avoided with routine maintenance of the recirculating pump and the entire hydronic heating system. Additionally, it can guarantee the system’s effectiveness and increase its lifespan. You may prevent future expensive repairs and replacements by performing routine maintenance and taking care of any problems as soon as they arise.

Conclusion

A hydronic heating system’s recirculating pump is a crucial part, and it can be annoying and difficult when it stops moving water. You can quickly fix your recirculating pump by knowing the typical causes of the issue and using our step-by-step troubleshooting guide. To ensure that the issue doesn’t arise again and that your system runs well, remember to perform routine maintenance on it.