Celestron 9.25″ Dew Heater Ring

Description

Celestron 9.25-inch Dew Heater Ring (Part #94052)

Permanent, efficient dew controlright at the glassfor your 9.25″ SCT or EdgeHD

The 9.25″ Schmidt-Cassegrain is something of a cult classicbig enough to dive deep, compact enough to travel, and optically sharper than many scopes twice its price. But its generous corrector plate is still vulnerable to one timeless enemy: dew.

The Celestron Dew Heater Ring offers a smarter, more efficient solution by warming the corrector glass directly, not the metal cell around it. It replaces your stock retaining ring and becomes a permanent, precision-machined part of your telescopeso you’ll never forget to pack it, and you’ll never deal with slipping heater straps again.

How it works

Where traditional dew straps waste energy warming the front housing, the Dew Heater Ring puts the heat exactly where its neededon the corrector itself. An internal resistive heating element runs evenly around the lens perimeter, and a built-in thermistor sensor communicates with Celestron’s Smart DewHeater Controllers (sold separately) to maintain just the right temperature in any conditions.

• Efficient, direct-contact heating preserves battery life and improves results

• Rigid aluminum construction supports both the corrector and internal circuitry

• Velvet-lined interior protects coatings while distributing clamping pressure

• Storage clips keep power and thermistor jacks secured when not in use

• Cable management clip mounts to the front cell for strain relief and cleaner routing

This is a permanent installationyou install it once, and your dew control becomes part of the telescope itself.

Easy, one-time installation

For Celestron 9.25″ OTAs made in 2006 or later, installation is a direct swap. Use the included paper installation shield to protect your corrector during the process. Remove the stock retaining ring, place the Dew Heater Ring in its place, and re-secure with the existing screws. The ring is designed to accommodate your telescopes standard dust cover and will not affect collimation.

Technical Specs

Feature	Description
Compatibility	9.25″ Celestron SCT and EdgeHD (2006 and newer)
Power Input	12V DC (5.5mm 2.1mm barrel connector, tip positive)
Power Draw	Approximately 2025 watts (controller-regulated)
Thermistor Jack	2.5mm audio plug, compatible with Celestron Smart DewHeater Controllers
Construction	Precision aluminum with velvet-lined interior
Included Accessories	Power jack extension cable, cable management clip, paper installation shield
Installation	Replaces existing corrector retaining ring (non-invasive, reversible)

Note: While compatible with third-party 12V controllers for heater function, the rings built-in thermistor sensor only works with Celestrons Smart Controllers.

Observing Tip

For even greater efficiency, pair this ring with a dew shield. Passive shielding reduces radiant cooling, which means your ring uses less powerand your battery lasts longer. A Smart Controller will throttle the output dynamically, conserving energy while still keeping your optics dew-free.

Final Thoughts

If youve made the smart choice with a 9.25″ SCT or EdgeHD, this is the dew solution to match. The Celestron Dew Heater Ring is efficient, permanent, and purpose-builtnot a workaround. It becomes part of your OTA, ready for action every night, no matter the forecast.

Newer generation Celestron SCTs built in the year 2006 or later are compatible with the Dew Heater Ring. These newer OTAs have a trilobed shape on the rear cell. In addition, newer generation 14″ SCTs have a rounded rear cell. See photo examples below. All EdgeHD, RASA, 6 Schmidt-Cassegrain and 9.25 Schmidt-Cassegrain telescopes are compatible with the Dew Heater Ring.

Enhance your setup

To achieve the highest level of dew prevention while maximizing power efficiency, we strongly recommend pairing the Dew Heater Ring with a Smart DewHeater Controller (sold separately). The controller uses the ring’s built-in thermistor and its internal environmental sensor to provide just the right amount of heat to the corrector to prevent dew based upon the ambient temperature, ambient humidity, and temperature of the Schmidt corrector, which can dramatically reduce the rings power draw, greatly increasing battery life. The ring also includes an extension cable for connecting the ring directly to one of the controllers heater output ports, or to a third-party controllers heater output port. (Note: the rings integrated thermistor is only compatible with the Celestron Smart DewHeater Controllers).

We also recommend adding a dew shield to your setup. While not mandatory, a shield will cut down on the amount of power the Dew Heater Ring needs to keep the optics clear.

Tech Details:

Max Power:	24 watts
Power Jack:	12V DC barrel connector, 5.5mm/2.1mm, tip positive
Ring construction:	Aluminum
Power Jack extension cable:	6″ long, 12V DC, 5.5mm/2.1mm barrel connector on one end, male RCA connector on other end, tip positive
Thermistor Jack:	2.5mm audio jack, compatible with Celestron SmartHeat Dew Controllers
Compatibility:	9.25″ Schmidt-Cassegrain, EdgeHD
Dew Heater Ring Inner Diameter:	235mm (9.25″)
Dew Heater Ring Outer Diameter:	261.1mm (10.28″)
Weight:	4.14 oz (117.5 g)
California Residents	View Proposition 65 Warning