{"product_id":"mcdonnell-miller-110800-proportion-switch-model-93-94-lwco","title":"McDonnell \u0026 Miller 110800 Proportion Switch – Model 93 \u0026 94 LWCO","description":"\u003cp\u003eThe proportion switch regulates the water‑to‑oil ratio in low‑water cutoff (LWCO) boilers to ensure optimal heat transfer and protect equipment. This **110800** unit is engineered specifically for Model 93 \u0026amp; 94 LWCO systems, delivering precise control and quick response.\u003c\/p\u003e\u003cp\u003eOperating via a pilot‑valve mechanism, the switch senses water level changes and adjusts the fuel flow accordingly. When low‑water is detected, it trips the boiler’s safety circuit, preventing dry‑fire conditions and extending system life.\u003c\/p\u003e\u003ch4\u003eKey System Performance Baselines:\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccurate Ratio Control:\u003c\/strong\u003e Maintains water‑to‑oil ratio within ±2%.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRapid Response:\u003c\/strong\u003e Trips low‑water condition in under 2 seconds.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurable Construction:\u003c\/strong\u003e Handles temperatures up to 500 °F.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow Maintenance:\u003c\/strong\u003e Self‑adjusting pilot reduces service intervals.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e⚠️ \u003cstrong\u003eApplication Profile:\u003c\/strong\u003e Ideal for commercial hot‑water heating, industrial boiler rooms, retrofit projects, and new LWCO boiler installations requiring reliable low‑water protection.\u003c\/p\u003e","brand":"McDonnell \u0026 Miller","offers":[{"title":"Default Title","offer_id":43123921289310,"sku":"110800","price":1805.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0663\/7151\/8558\/files\/110800_image_7f94cf65-2d2e-43b6-b1eb-435da6f8d4db.png?v=1786022917","url":"https:\/\/nationalboilersupply.com\/products\/mcdonnell-miller-110800-proportion-switch-model-93-94-lwco","provider":"National Boiler Supply","version":"1.0","type":"link"}