Aladdin - Universal Pressure Switch, SPST Pilot Duty, 1/8in w/ Fittings, 1-5 PSI Adj., 3925

Aladdin Universal Pressure Switch for millivolt Gas heaters used on spas and pools, 3925. SPNO, Normally Open, 25 Amp water pressure switch has two 1/4"" standard tab wire terminals, Common and NO. Water connection is made directly with the 1/8"" NPT threads, or by means of the 3 included brass adapters for flexible hose, copper hose, or 1/4"" hose fittings. Tridelta/Tecmark pressure switch 3925 pressure switch, used on older gas heaters by Zodiac (Jandy/Laars), Raypak and other heaters and also can be used on many new heaters, without the need for the adapters./p>

Pressure switches are used on spa, tub and bath heaters to measure the amount of water pressure inside of the heater, as an approximation of water flow. Pressure switches are safety devices intended to prevent heater damage and overheated water hazards. If your pressure switch is causing the heater to shut down, look for causes of low flow in and out of the heater, and remove the spa filter temporarily to improve flow. Pressure switches do fail eventually (which is why sell replacements), but first assume a flow problem, and not a switch problem.

Adjustable Pressure Switch comes factory set but can be adjusted from 1 to 5 psi. Pressure switches do not normally need adjustment after installation, and to avoid heater damage or overheated water, large adjustments should be avoided. 1-2 psi is the correct setting for most spas, tubs and whirlpools. High Altitude locations or spa systems located several feet Below the spa, may need 3-5 psi settings. Refer to your spa heater manual or heater documentation, for any instructions on heater pressure switch settings.