The Pressure Tuner in Lunt Solar Systems’ solar telescopes incorporates a rubber O-ring to seal the air pressure tuning system. Over time, the rubber in this O-ring can age and become porous, meaning that the air pressure can no longer be maintained. The old O-ring can then be replaced with this spare part. Replacement is straightforward and can be carried out by the user.
After replacing the O-ring, the piston and cylinder of the pressure tuner can be re-greased with ‘ Lunt Solar Systems Spare Teflon-Lubricant for O-Ring PT-Piston ’.
Contents: one O-ring with an internal diameter of 34 mm and an external diameter of 42 mm for the Pressure-Tuner on Lunt Solar Systems’ MT and THa-H-Alpha solar telescopes
Please note: Depending on the production series, the diameters of the Pressure Tuner pistons may vary slightly. There are pistons for O-rings with an inner diameter of 32 mm and an outer diameter of 40 mm, and pistons for O-rings with an inner diameter of 34 mm and an outer diameter of 42 mm. Please check the diameter of your old O-rings.
