Watson McDaniel Company is a manufacturer of steam and fluid specialty products, including steam traps, regulators, pumps and control valves, based in Pottstown, Pennsylvania. Its traps pass condensate and air out of steam lines and equipment while holding back live steam, and its regulators hold a set pressure or temperature downstream of a steam supply.
BoilerSupplies.com carries the Watson McDaniel steam trap series, thermodynamic steam traps, radiator steam traps and float and thermostatic kits on the trap side. On the control side it carries pressure reducing and regulating valves and temperature regulating valves. A trap is chosen by type first: float and thermostatic for steady drainage under modulating loads, thermodynamic for high pressure mains and tracing, radiator traps for radiators and convectors. Then it is sized by pressure, condensate load and connection. A regulator is chosen by inlet pressure, the set point, the flow and the body size.
Key facts
Watson McDaniel Company, based in Pottstown, Pennsylvania, makes steam traps, regulators, pumps and control valves.
BoilerSupplies.com lists Watson McDaniel thermodynamic steam traps, radiator steam traps and the Watson McDaniel steam trap series.
Watson McDaniel float and thermostatic kits carry the replacement internals for a float and thermostatic trap.
Watson McDaniel pressure reducing and regulating valves and temperature regulating valves are on the page beside the traps.
In-stock small-pack orders placed before 2:00 PM EST, Monday through Friday, ship the same day.
A trap that has failed open blows live steam into the return: the return line runs hot, the receiver vents steam and the boiler takes more makeup water. A trap that has failed closed backs up condensate, so the coil runs cold and water hammer starts. Either way the trap gets replaced or rebuilt; radiator traps and float and thermostatic kits are on BoilerSupplies.com.
Those are two Watson McDaniel traps. Thermodynamic trap, disc trap and TD trap all name the same trap: a single disc that snaps shut on flash steam, used on high pressure mains and tracing. F&T trap, float and thermostatic trap and float trap name the trap with a float for condensate and a thermostatic air vent, used on coils and unit heaters. Watson McDaniel makes both; BoilerSupplies.com lists both.
The pressure reducing valve holds a set downstream steam pressure; the temperature regulating valve holds a set temperature. The reducing valve keeps that outlet pressure as the inlet pressure and the flow change. The temperature regulating valve modulates steam or water flow to hold a tank, heat exchanger or process at temperature, using a sensing bulb in the fluid. Both are listed under Watson McDaniel on BoilerSupplies.com.
Trap first: the type (float and thermostatic, thermodynamic or radiator), the model and size off the body, the inlet pressure, the connection (threaded size or flange) and what it drains. Regulator: inlet pressure, required outlet pressure or temperature, flow or load, body size and the fluid. A photo of the old unit's nameplate covers most of it.
Yes, where the body is sound. The float and thermostatic kits on BoilerSupplies.com carry the replacement internals for a Watson McDaniel float and thermostatic trap. Order the kit by the trap model and size on the body. A cracked body, a stripped cover thread or a trap that has been welded on takes a new trap.
To quote a Watson McDaniel trap or valve, BoilerSupplies.com needs the model, size, connection and operating pressure, through the site or by phone at 1-770-957-9599, toll free 1-800-780-3776.
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