Nicholson

A Nicholson thermostatic steam trap drains condensate from a steam line or the equipment on it, and the capsule inside is its working part. That capsule is a thermostatic element that lets condensate through and closes against steam.

BoilerSupplies.com carries one part for Nicholson traps: the steam trap capsule. It stays open for cooler condensate and shuts on steam. Failed open, it passes steam into the return; failed closed, it backs condensate up into the line or equipment the trap drains. A capsule is ordered by the trap it goes into, not by its own size, so the trap's markings or the old capsule are the starting point.

Key facts

• BoilerSupplies.com lists steam trap capsules for Nicholson thermostatic traps.

• A thermostatic capsule stays open for cooler condensate and shuts on steam.

• A capsule that has failed open passes steam into the return; one that has failed closed backs condensate up.

• A thermostatic capsule is ordered by the trap it goes into.

• In-stock small-pack orders placed before 2:00 PM EST, Monday through Friday, ship the same day.

What do mechanics mean by a Nicholson bellows?

The thermostatic element inside a Nicholson thermostatic trap, the part BoilerSupplies.com lists as Nicholson Steam Trap Capsules. Many of these elements are built as a bellows, which is where the name comes from, and the trade also calls it an element, a capsule or a cartridge. It closes on steam and opens on cooler condensate.

How is the right Nicholson capsule matched to my trap?

From the trap, not from the capsule's own dimensions. Read the marking cast or stamped on the Nicholson trap body, or photograph the old capsule once it is out, and send that through BoilerSupplies.com with the quantity. Capsules that look close can belong to different traps, so the trap is the reference.

What are the signs a Nicholson thermostatic trap needs a new capsule?

Steam blowing through the trap into the return usually points to a capsule that has failed open. A trap that stays cold while the line or equipment upstream fills with condensate points to one that has failed closed, and that can show as water hammer or slow heat-up. Either way, a new capsule is a common repair.

Does a failed Nicholson capsule mean a new trap?

Not always. The capsule is the replaceable working part of a Nicholson thermostatic trap, which is why BoilerSupplies.com lists it on its own. Whether a job needs more than a capsule depends on the trap in the line, so send its markings or a picture of the spent capsule, with the quantity.

A photo of the Nicholson trap markings or of the spent capsule, with the count, is what to send through BoilerSupplies.com. Boiler USA also answers at 1-770-957-9599, toll free 1-800-780-3776.