SOS-2 – FLOAT SWITCH

Condensate overflow safety switch, companion to the SOS-1 overflow switch. It opens the low-voltage control circuit when the drain line or pan backs up, shutting the equipment down before water damage occurs. No current manufacturer datasheet exists under this number, so contact rating, mounting style and reset behaviour are unconfirmed – verify before wiring.

Specifications from our own stock records. The manufacturer does not publish a public page for this item.

Specs

• TypeCondensate overflow safety switch
• FunctionOpens the control circuit on drain line or drain pan overflow
• ContactsNormally closed when dry - verify on the part
• Control voltageNot published - verify before wiring
• ResetNot confirmed
• Data SourceOTP stock record - not manufacturer-verified

What does a condensate float switch do?

It is a normally closed switch in the 24 volt control circuit that opens when water rises. The primary switch goes in the drain line at a tee or in the primary pan. The secondary sits in the emergency pan under an attic air handler. When it opens, the system stops making condensate before the pan overflows into your ceiling.

My AC quit in the middle of a hot week. Could this be it?

Very possibly, and on a Dallas attic unit it is one of the first things to check. Our cooling season runs most of the year, drains grow algae, and a slow trap or a flat run of PVC is all it takes. If the thermostat went blank, the switch is probably breaking R. If the blower runs and the outdoor unit does nothing, it is probably breaking Y.

Should mine break R or Y?

Breaking R shuts the system down and blanks the thermostat, so the problem gets noticed immediately and the coil stops sweating. Breaking Y stops the compressor but leaves the blower running, which in DFW humidity can re-evaporate pan water right back into the house. Most people here are better off breaking R. If you have more than one float switch, wire them in series.

Can I bypass it until I get the drain cleared?

No. Clear the drain. A jumper across a float switch is how a stained ceiling turns into a drywall job.