HH18HA496 – LIMIT SWITCH (MALB, 200)

Temperature limit switch for Carrier, Bryant and Payne furnaces, recorded in our system as style MALB with a 200 degree F setting. It opens the low-voltage control circuit when the sensed temperature reaches the set point, shutting down heating on restricted airflow or blower failure. Limit switches must match on both mounting style and temperature rating. Carrier publishes no public part detail, so the specifications below come from our own stock records; confirm against the part nameplate before installing.

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

Before you order

Same furnace families as HH18HA504 but a different size and temperature — that is exactly why the two are not interchangeable. The 310, 311 and 312 series are the Bryant, Payne and Day & Night versions of the same chassis. Published application data. Always match the full model and serial number on your unit before ordering.

Specs

• Part NumberHH18HA496
• Brand (as recorded)Carrier
• Product TypeFurnace limit switch
• Style (as recorded)MALB (large base)
• Limit Setting200 degrees F
• FunctionOpens control circuit on over-temperature
• Data SourceOTP stock record - not manufacturer-verified

Fits these models

• 58STA110 series (10016, 10116, 11116, 14116, 16116, E10116)
• 58STX110 series (10116, 11116, 12116, 13116, 14116, 16116, E10116)
• 58DLA110 series (10016, 10116, 11116, 12116, 13116, 14116)
• 58DLX110 series (10016, 10116, 11116, 12116, 13116, 14116)
• 58CTA110 series (10016, 10116, 11116, 12116, 13116, 14116)
• 58CTX110 series (10116, 11116, 12116, 13116, 14116)
• 310AAV048110 and 310JAV048110 (AA, AB, AC, AD, AE, AG, EA – JA)
• 311AAV048110 and 311JAV048110 (AA, AB, AC, AD, AE – JA)
• 312AAV048110 and 312JAV048110 (AA, AB, AC, AD, AE – JA)

What does L200-40 mean on a furnace limit switch?

L is limit, 200 is the temperature in F where the contacts open on a rise, and 40 is the differential, so it closes back around 160F. That is an auto-reset disc. Manual-reset limits have a button and stay open until somebody pushes it. Bring the old one in so we can match the temperature, the mounting hole pattern, and the probe length together.

My limit keeps tripping. Is the switch bad?

Usually not. A limit is a safety reading real heat, and most repeat trips we hear about trace back to airflow - a loaded filter, closed or blocked registers, an undersized return, a dirty blower wheel, or a plugged evaporator coil sitting above the heat exchanger. Check temperature rise against the nameplate range, often 40-70F or 45-75F. Rise above the top number means airflow, not a bad switch.

Can I use a hotter limit if that is what is in stock?

No. L200, L230, L250 and L290 differ only by trip temperature and by base or probe size, and they are not interchangeable. Dropping a hotter limit into a furnace that specced a cooler one lets the heat exchanger run past the temperature it was tested to. That is defeating the safety, not fixing it.

Does insertion length matter?

Yes. A 3 inch probe where 5 inch was called for sits in the wrong part of the airstream, reads low, and trips late or never. Measure the old probe from the back of the mounting plate to the tip.