{"product_id":"pentair-77707-0253-air-combustion-blower-kit-mastertemp-400na-max-e-therm-sr400na-natural-gas-genuine-oem","title":"Pentair 77707-0253 Air Combustion Blower Kit — MasterTemp 400NA \u0026 Max-E-Thermostat SR400NA, Natural Gas — Genuine OEM","description":"\u003cp\u003eThe \u003cstrong\u003ePentair 77707-0253 Air Combustion Blower Kit\u003c\/strong\u003e is the genuine OEM blower assembly for \u003cstrong\u003enatural gas\u003c\/strong\u003e MasterTemp 400 and Sta-Rite Max-E-Therm 400 pool and spa heaters. The blower drives the forced-draft combustion system — without it the heater will not fire.\u003c\/p\u003e\n\n\u003ch2\u003e⚠️ Natural Gas Only\u003c\/h2\u003e\n\u003cp\u003eThis kit is for \u003cstrong\u003enatural gas\u003c\/strong\u003e 400NA models. Propane units take a different blower kit. Check your heater's fuel type before ordering.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eGenuine Pentair OEM:\u003c\/strong\u003e Correct blower speed and housing for the 400K natural gas combustion system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRestores combustion performance:\u003c\/strong\u003e Addresses no-ignition, lockout and airflow-related fault codes traced to a failed blower.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComplete kit:\u003c\/strong\u003e Supplied as an assembly rather than a bare motor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eForced-draft design:\u003c\/strong\u003e The blower is what makes the MasterTemp's sealed combustion and high efficiency possible.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 77707-0253\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Air combustion blower kit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuel:\u003c\/strong\u003e Natural gas only\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCapacity:\u003c\/strong\u003e 400,000 BTU models\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits:\u003c\/strong\u003e Pentair MasterTemp 400NA; Sta-Rite Max-E-Therm SR400NA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeater Model:\u003c\/strong\u003e 460736\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePropane Equivalent:\u003c\/strong\u003e Different part — confirm fuel type before ordering\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Pentair \/ Sta-Rite (Genuine OEM)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eWill this fit my propane heater?\u003c\/h3\u003e\n\u003cp\u003eNo. The 77707-0253 is the natural gas kit. Propane models use a different blower assembly — 77707-0254 covers the 175LP and 200LP, and larger propane models have their own part numbers.\u003c\/p\u003e\n\n\u003ch3\u003eWhat symptoms point to a failed blower?\u003c\/h3\u003e\n\u003cp\u003eThe heater not firing at all, repeated ignition lockouts, unusual noise from the blower housing, or airflow and pressure-switch fault codes once the switch itself has been ruled out.\u003c\/p\u003e\n\n\u003ch3\u003eDoes it fit smaller MasterTemp heaters?\u003c\/h3\u003e\n\u003cp\u003eNo. This is the 400K assembly. The 175K, 200K, 250K, 300K and 333K models each use different blower kits.\u003c\/p\u003e\n\n\u003ch3\u003eIs the motor sold separately?\u003c\/h3\u003e\n\u003cp\u003eThis is supplied as a complete kit. Pentair does not generally sell the blower motor as a standalone component for this model.\u003c\/p\u003e\n\n\u003ch3\u003eWho should install it?\u003c\/h3\u003e\n\u003cp\u003eA qualified pool heater technician. The blower sits within the sealed combustion system and correct reassembly matters for safe operation.\u003c\/p\u003e\n\u003cdiv class=\"ps4u-faq\"\u003e\n\u003ch2\u003eFrequently asked questions\u003c\/h2\u003e\n\u003ch3\u003eHow do I size a pool heater?\u003c\/h3\u003e\n\u003cp\u003eHeater sizing follows pool surface area, the temperature rise you want and how exposed the pool is to wind. A larger BTU rating heats faster and cycles less; an undersized heater runs continuously and still struggles on cold nights. Gas heaters also need a gas line and meter capacity that can supply their rated input.\u003c\/p\u003e\n\u003ch3\u003eWhat is the part number for this heater component?\u003c\/h3\u003e\n\u003cp\u003ePentair lists this heater component under part number 77707-0253. Quote 77707-0253 when you cross-reference against your equipment manual, an existing part, or a parts diagram, so you are comparing the same revision.\u003c\/p\u003e\n\u003ch3\u003eWhat routine maintenance does a pool heater need?\u003c\/h3\u003e\n\u003cp\u003eKeep water chemistry balanced, because low pH and high calcium hardness are the two most common causes of premature heat exchanger failure. Beyond that: keep the cabinet clear of debris, check for rodent nests before each season, and have the burner and gas train inspected periodically.\u003c\/p\u003e\n\u003ch3\u003eHow do I confirm this fits my equipment?\u003c\/h3\u003e\n\u003cp\u003eMatch the part number stamped on the component you are replacing, or look it up in the parts list for your Pentair equipment. If your model or serial number is not named on this page, send it to us before you order and we will confirm the fit.\u003c\/p\u003e\n\u003ch3\u003eIs this the complete heater or a replacement part?\u003c\/h3\u003e\n\u003cp\u003eCheck the title and the specification section above. Heater listings and heater component listings share the same part-number format, so confirm whether you are buying a full appliance or a single serviceable component before ordering.\u003c\/p\u003e\n\u003ch3\u003eIs there a warranty on this heater component?\u003c\/h3\u003e\n\u003cp\u003eIt carries the standard Pentair manufacturer warranty. The terms are set by Pentair, and on some equipment the coverage only applies when a licensed professional performs the installation. Keep the receipt and packaging until you have confirmed correct operation.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":52911967437117,"sku":"77707-0253","price":629.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0968\/6741\/8429\/files\/OIP_8.webp?v=1787342121","url":"https:\/\/poolsupply4u.com\/products\/pentair-77707-0253-air-combustion-blower-kit-mastertemp-400na-max-e-therm-sr400na-natural-gas-genuine-oem","provider":"PoolSupply 4U","version":"1.0","type":"link"}