{"product_id":"honeywell-l404f1243","title":"Honeywell L404F1243 Pressuretrol Controller","description":"\u003cp\u003eThe \u003cstrong\u003eHoneywell L404F1243 Pressuretrol Controller\u003c\/strong\u003e is an \u003cstrong\u003eautomatic-recycle pressure control\u003c\/strong\u003e from the \u003cstrong\u003eL404F series\u003c\/strong\u003e, built to start and stop a burner or switch a control circuit as \u003cstrong\u003eboiler pressure\u003c\/strong\u003e rises and falls. This model covers an adjustable range of \u003cstrong\u003e5 to 50 PSI\u003c\/strong\u003e with an adjustable \u003cstrong\u003e6 to 14 PSI differential\u003c\/strong\u003e, and it connects to the pressure source through a \u003cstrong\u003e1\/4\" NPT\u003c\/strong\u003e internal-thread fitting on the diaphragm. The switch is a \u003cstrong\u003esnap-acting SPDT\u003c\/strong\u003e (single-pole, double-throw) design: when pressure rises to the setpoint the \u003cstrong\u003eR-W\u003c\/strong\u003e contacts make and the \u003cstrong\u003eR-B\u003c\/strong\u003e contacts break, and both flip back as pressure falls by the differential. It is a \u003cstrong\u003eline-voltage\u003c\/strong\u003e control rated for \u003cstrong\u003e120\/240 Vac\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003cp\u003eUnderstanding how the \u003cstrong\u003eL404F1243\u003c\/strong\u003e works makes setup and troubleshooting much easier. System pressure acts on the \u003cstrong\u003ediaphragm\u003c\/strong\u003e behind the hex fitting, and that force is balanced against a calibrated spring you set with the \u003cstrong\u003emain scale adjusting screw\u003c\/strong\u003e on top of the case. The \u003cstrong\u003edifferential adjusting screw\u003c\/strong\u003e sets how far pressure must fall below the setpoint before the switch recycles. Because the \u003cstrong\u003eL404F\u003c\/strong\u003e uses a \u003cstrong\u003esubtractive differential\u003c\/strong\u003e, the differential is subtracted from the main scale setting, so a 15 PSI setpoint with a 6 PSI differential recycles at roughly 9 PSI. The contacts are rated \u003cstrong\u003e8.0 amps full-load at 120 Vac\u003c\/strong\u003e and \u003cstrong\u003e5.1 amps full-load at 240 Vac\u003c\/strong\u003e, so use a relay or contactor for larger loads. Honeywell also builds the \u003cstrong\u003eL404F\u003c\/strong\u003e in \u003cstrong\u003e2-15 PSI\u003c\/strong\u003e, \u003cstrong\u003e10-150 PSI\u003c\/strong\u003e and \u003cstrong\u003e20-300 PSI\u003c\/strong\u003e ranges, which are different controls from this \u003cstrong\u003e5-50 PSI\u003c\/strong\u003e model.\u003c\/p\u003e\n\n\u003cp\u003eOn steam service, always pipe the \u003cstrong\u003eL404F1243\u003c\/strong\u003e through a \u003cstrong\u003esiphon loop (pigtail)\u003c\/strong\u003e so a cushion of condensate, not live steam, sits against the diaphragm. After setting the \u003cstrong\u003emain scale\u003c\/strong\u003e, confirm the actual cut-out with a \u003cstrong\u003etest gauge\u003c\/strong\u003e on the same boiler, because the printed scale is a guide and not a substitute for a gauge. Typical failure signs are \u003cstrong\u003eshort-cycling\u003c\/strong\u003e from a differential set too tight or a plugged siphon, a \u003cstrong\u003eburner that will not fire\u003c\/strong\u003e from burned or open \u003cstrong\u003eR-W\u003c\/strong\u003e contacts, and \u003cstrong\u003epressure climbing past the setpoint\u003c\/strong\u003e from welded contacts. With power off, meter continuity across \u003cstrong\u003eR-W\u003c\/strong\u003e and \u003cstrong\u003eR-B\u003c\/strong\u003e while you raise and lower pressure; they should swap at the setpoint. Replace it with a control of the same \u003cstrong\u003e5-50 PSI\u003c\/strong\u003e range and \u003cstrong\u003eauto-recycle\u003c\/strong\u003e action, never a manual-reset limit, and keep the boiler's separate \u003cstrong\u003ehigh-limit\u003c\/strong\u003e and \u003cstrong\u003esafety relief valve\u003c\/strong\u003e in place as code requires.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eKey Benefits\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAuto-Recycle Operation:\u003c\/strong\u003e The \u003cstrong\u003eL404F1243\u003c\/strong\u003e resets itself when pressure falls by the differential, so the boiler cycles automatically without a manual reset.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e5-50 PSI Adjustable Range:\u003c\/strong\u003e One control covers the common low-pressure and medium-pressure \u003cstrong\u003esteam boiler\u003c\/strong\u003e setpoints with a \u003cstrong\u003emain scale\u003c\/strong\u003e you can set on site.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e6-14 PSI Adjustable Differential:\u003c\/strong\u003e The \u003cstrong\u003edifferential adjusting screw\u003c\/strong\u003e lets you widen the cycle to reduce \u003cstrong\u003eshort-cycling\u003c\/strong\u003e or tighten it for steadier pressure.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSPDT Snap-Acting Switch:\u003c\/strong\u003e The \u003cstrong\u003eR-W\u003c\/strong\u003e make and \u003cstrong\u003eR-B\u003c\/strong\u003e break contacts give crisp switching and let a single control change over between two circuits.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003eCommon Questions\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eWhat does auto recycle mean?\u003c\/strong\u003e The contacts reset on their own once pressure drops by the \u003cstrong\u003edifferential\u003c\/strong\u003e. A manual-reset control stays tripped until someone presses a button, so the two are not interchangeable.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eWhat pressure range and differential does the L404F1243 cover?\u003c\/strong\u003e The \u003cstrong\u003eL404F1243\u003c\/strong\u003e is a \u003cstrong\u003e5 to 50 PSI\u003c\/strong\u003e control with an adjustable \u003cstrong\u003e6 to 14 PSI\u003c\/strong\u003e differential, set with the \u003cstrong\u003emain scale\u003c\/strong\u003e and \u003cstrong\u003edifferential\u003c\/strong\u003e screws.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eHow is it connected?\u003c\/strong\u003e Pipe it to the boiler through a \u003cstrong\u003esiphon loop\u003c\/strong\u003e using the \u003cstrong\u003e1\/4\" NPT\u003c\/strong\u003e fitting, then wire it to the burner circuit at \u003cstrong\u003e120\/240 Vac\u003c\/strong\u003e using the \u003cstrong\u003eR\u003c\/strong\u003e, \u003cstrong\u003eW\u003c\/strong\u003e and \u003cstrong\u003eB\u003c\/strong\u003e terminals.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eDisclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.\u003c\/p\u003e","brand":"Honeywell","offers":[{"title":"Default Title","offer_id":67643389903026,"sku":"L404F1243","price":492.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1838\/2375\/files\/L404F1243.jpg?v=1791314270","url":"https:\/\/www.gsistore.com\/en-ca\/products\/honeywell-l404f1243","provider":"GSIstore","version":"1.0","type":"link"}