Steam systems often go unnoticed as the biggest energy wasters. Steam trap failures can easily occur and go unnoticed. Like any mechanical system which moves, parts will wear and/or break. However, the steam system will still provide heat, so red flags don’t go up—but energy dollars go out the door!
To put it simply, a steam heating system consists of:
Typically, the radiators or coils are equipped with a metering device on the inlet to control the amount of steam flow and therefore the heat is given off by the radiator. On the outlet of the register or coil is the steam trap, which typically allows build up condensate to leave using a float to regulate condensate level. Return piping then carries the condensate back to a tank and pump where it is collected and returned to the boiler to start the process over again.
Proper (efficient) heat transfer within the radiator or heating coil requires that the steam condenses within the coil. Changing state from steam to water provides a far greater heat output than simply steam flowing through the register. To ensure the steam is condensing inside the register or coil, the steam trap traps the steam inside and doesn’t allow it to leave until it is in condensate form. When the trap fails to close, which is rare, the register goes cold as if it were clogged and is easily noticed.
When the trap fails to seal and constantly allows flow, it is much harder to identify. In this case, the register will still give off heat. And if the system or building is large (100-200 radiators) and only one fails, it will be difficult to notice the change in fuel usage (but it is there!). As more and more traps fail and allow steam to flow through, the heating cost will continue to increase. The cost can go up as much as 30% when half of the traps begin leaking, which will likely go unnoticed as it happens slowly over the years.
So, what can you do? And is it worth it?
Here are a few easy, cost-effective ways to maintain your steam systems, preventing increased energy costs.
Keep Them Clean: Dirty or hard water can leave deposits that can destroy or inhibit seals in traps. Conduct a proper blow down and be sure the make up water source is filtered or treated as necessary. System additives may also help, as recommended by your mechanical service group.
Schedule Inspections: Mechanical traps should be inspected annually with a suitable non-contact thermometer or thermal imaging camera, if available.
Rebuild Regularly: Traps found to be leaking and typically any trap over 3–5 years should be rebuilt. The rebuild of a mechanical trap typically requires simply opening, flushing out any accumulated deposits or debris, and replacing the seal.
For those who think they don’t have the time to maintain their steam systems properly, consider the following example. A fairly large, three-story building has a $20,000 annual heating fuel bill. If half the steam traps fail, we estimate that the bill would increase by approximately $5000. Locating and fixing these traps would likely take about five days or 40 hours. Assuming an hourly rate of $50/hour, the effort costs you $2,000. You just spent $2,000 to get back $5000 per year. Yes, you can make time for that!
In addition to the simple savings, you would save wear and tear on the boiler (a much more significant expense to replace). If you can’t bear to think of losing one of your team for 40 hours, consider that preventive maintenance tends to be half the effort of repair maintenance. So now, we are down to 20 hours. That’s a little more than half an hour a week.
Remember, just because your boiler is running, doesn’t mean it’s running efficiently! Whether you’ve noticed your energy bills creeping up or it’s just been a while since you looked at our steam systems, we can help. Our Engineers can help you assess your current situation and provide expert recommendations. Contact us today!