If your furnace is short-cycling, check the filter first — a clogged filter causes the limit switch to trip. If the filter is clean, then the switch itself may be failing.
SHL509 – HIGH TEMPERATURE LIMIT SWITCH (3″, L240°)
$35.14
Supco SHL509 high limit switch, 3-inch insertion, opens at 240°F, closes at 210°F. Auto reset. Crosses to Carrier HH12ZB240. Universal furnace replacement.
Mon–Fri 10 am – 7 pm | Sat 10 am – 3 pm | In-Store Pickup Only
Description
If your furnace is short-cycling (turning on and off repeatedly), a failed limit switch may be the cause. This 3-inch high limit switch opens at 240°F and auto-resets when temperature drops back to 210°F. Crosses directly to the Carrier HH12ZB240.
Specs: Opens at 240°F, closes at 210°F, auto reset, 3.12-inch insertion, SPST
Replaces: SHL509, HH12ZB240
Fits: Carrier/Bryant/Payne furnaces calling for HH12ZB240. Also fits other brands using a 3-inch L240 high limit switch.
Need help? See our Furnace Short Cycling Guide.
In stock at Open To Public HVAC Parts in Dallas. We test parts at the counter before you buy. Call or text (214) 340-9421.
