Rothenberger 1099931 Ratchet Wrench 1/4 - 3/16 - 3/8 - 5/16 inch – AC and Refrigeration Service Valve Wrench

The Rothenberger 1099931 is a double-ended ratchet wrench used to turn square-stem valves in refrigeration and air conditioning systems. One end has 3/16 and 1/4 inch square openings and the other 5/16 and 3/8 inch, so the four sizes encountered in the field are covered by a single tool. The body is chrome-plated steel.

The ratchet mechanism is reversible: the valve is opened or closed without having to pull the handle back and re-engage it. This is what really makes the difference when working in tight spaces — inside a condensing unit, on valves tucked between bundles of tubing, there is often no room to turn a regular wrench.

Which Valves Is It Used On?

• Compressor suction and discharge service valves. The back-seated, front-seated and mid-seated positions of the valve are set with this wrench.
• Liquid receiver main valve. Used when isolating the system on the discharge side.
• Refrigerant cylinder and acetylene cylinder valves. The square stems of cylinder valves are mostly 1/4 and 5/16 inch.
• Thermostatic expansion valve (TXV) adjusting stem. Lets you turn the stem without rounding off its corners when adjusting superheat.
• Fan and pulley set screws. Used on 5/16 inch square-head set screws.

Square or Hex? Check Before Ordering

This wrench is for square-stem valves. The outdoor unit valves of residential split air conditioners, which are common in Turkey, are opened with a hex (Allen) key — for those you need a hex key set, not this wrench. Check the cross-section of the stem of the valve you are going to work on: if it is square, this tool is right; if it is hexagonal, a hex key set is. Technicians who carry both can service either type of unit.

Turning a square-stem valve with an adjustable wrench or pliers rounds off the corners of the stem; once rounded, the stem will never be gripped by any wrench again and the whole valve body has to be replaced. That is exactly why the square-opening wrench exists.

Technical Specifications

• Brand: Rothenberger
• Product Code: 1099931
• Type: Double-ended square-opening ratchet wrench (square ratchet)
• Sizes: 3/16 and 1/4 inch (one end) · 5/16 and 3/8 inch (other end)
• Mechanism: Reversible ratchet
• Body: Chrome-plated steel
• Packaging: Original Rothenberger hanging blister pack

Usage Notes

• Seat the wrench fully on the stem; forcing it with a partial grip damages both the stem and the opening.
• Select the ratchet direction to suit the job; a mechanism forced in the wrong direction will skip teeth.
• If the valve stems are seized, apply penetrating oil first; do not extend the handle to increase torque.
• When working on cylinder valves, remember that you are working under gas pressure; open the valve slowly.