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June 24th, 2021Antler Pumps – Steam Condensate Pump Troubleshooting for Your Boiler System
Steam Condensate Pump Troubleshooting for Your Boiler System
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While the general physics behind a boiler system isn’t too complicated, there are multiple components that can act up and cause trouble. One element that our clients at Antler Pumps frequently need service for is the steam condensate pump. Read on to learn about the vital role of this pump and steam condensate pump troubleshooting. Some of the problems experienced with this pump you can remedy yourself, and others may require help from pump professionals.
What Is the Role of the Steam Condensate Pump?
An essential part of your boiler system
In a closed boiler system, condensate is returned from radiators after steam cools, so the water can be reheated and used again. The typical New York City apartment boiler repeats this cycle over and over again as part of the heating process.
The system must maintain a positive pressure differential from the source (radiators in various units) to the destination (a return header or collection area). Occasionally, this requires the assistance of a steam condensate pump, as the pressure in the system isn’t enough on its own. This pump also helps overcome friction and any residue in the line that slows the return of condensate to the boiler room.
Therefore, your steam condensate pump is an important component of your heating cycle. Without it, you would have noisy pipes, a higher water bill, and much less efficient radiator heating.
What Are Some Typical Steam Condensate Pump Problems?
Sediment in the water
Bits of rust and other undesirable material in your pipes can work their way into your steam condensate pump over time. This can affect the pump’s operation, such as damaging the shaft or weakening the seals. A good cleaning of the system with trisodium phosphate can prevent that from recurring.
Dirty strainer
The inlet to your pump should be protected with a strainer to catch any of the aforementioned sediment or other unwanted substances. However, this means that the strainer has to be cleaned periodically, at least at the end of every heating season. A clogged strainer can keep condensate from returning to the boiler. Signs that a dirty strainer might be the culprit include the boiler feeder operating more frequently than it should to replace the missing condensate and water hammer in your pipes.
Poor mechanical seal
Cracked and worn seals can cause your steam condensate pump to fail. Sometimes, this happens because of wear and tear on old pumps. Another common cause is erosion from carbonic acid created by an incorrect water pH. The pH of your boiler water should be between seven and nine (alkaline), which you can check with litmus testing and adjust accordingly. Be sure to fix any seals that were previously damaged due to the presence of acidic water.
Cavitation
Cavitation is one of the worst types of pump failure we see. It occurs when water flashes into vapor because the condensate is too hot. It can ruin a pump’s impellers very quickly and cause further damage to your boiler tank. Usually, this means we need to repair or add steam traps to the system to keep ultra-hot condensate from trying to rush into the return.
Excessively high boiler pressure
Remember, your steam condensate pump was installed because you need to create a pressure differential between the source of the steam returning to the system and the collection area. However, this pressure gradient won’t exist if the pressure in the boiler is set too high. When this happens, little to no condensate comes back to the boiler. We can help you adjust the boiler pressure so your pump works optimally and returns as much condensate as possible.
Issues with the check valve
A check valve keeps your boiler water from flowing in the wrong direction to the condensate receiver. If sludge builds up along the check valve, it won’t close properly, and water will seep into the receiver, triggering the float switch and starting the pump. This can also improperly cue your boiler feeder to start. If these two pumps are running more than usual, examine the check valve function:
- Close the service valve at the condensate pump inlet.
- Wait until water stops flowing into the pump’s receiver.
- Listen for the pump to keep trying to cycle, which means water is coming from the boiler itself, not the radiator return system.
Malfunctioning float rod
Like in other boiler elements, the condensate pump has a float switch that turns the motor on and off. When the water level rises in the receiver, it turns the pump on, and when the level drops, the pump shuts off. A loose or old ball on the end of the float rod can cause this mechanism to fail. This is one steam condensate pump troubleshooting area that most property owners or managers can usually fix themselves.
Other possibilities
While the list above contains the most common steam condensate pump problems, there are a couple of other reasons it might not be working properly:
- Boiler vacuum – formed when steam condenses and pressure in the receiver becomes higher than the pressure in the boiler, requiring a vacuum breaker
- Master trap not working properly – causes steam to be released at too high of a temperature and must be replaced or repositioned
- Electrical problems with the pump – faulty/worn wiring or wrong voltage, which must be repaired or upgraded
- Overheated boiler room – causes electric motor failure until the ambient temperature is lowered
- Pump discharge into a Hartford loop – may need to be reconfigured, since a Hartford loop is really intended for a gravity-return system
- Clogged impeller – requires cleaning of the pump’s interior
- Plugged vent line – air can’t escape from the system and the vent will need cleaning
What Should You Do If You Suspect Your Steam Condensate Pump Isn’t Working Properly?
Call Antler Pumps for fast, expert service
Without a fully operational steam condensate pump, your heating system could suffer premature wear and tear, energy waste, high water bills, or even failure. If you have a problem with your pump and can’t fix it yourself, Antler Pumps is happy to come by to evaluate it for repair, cleaning, or replacement.
Call us today at 212-534-2500, or book an appointment online. Summer is the perfect time to take care of your heating system before you need it to run again.