PELCO® EM Pro Vacuum Chamber

The PELCO® EM Pro Vacuum Chamber is designed for use inside all PELCO BioWave® series microwave processors. The chamber is made of chemically resistant, microwave transparent polypropylene and designed for vacuums down to 20” of Hg and temperatures up to 70°C.

Figure 1. Chamber components

Top Plate (A) and Base Unit (B) form the chamber with the L-gasket (C). The Base Unit is fitted with a ¼" Barb Fitting (D) to attach the vacuum hose. The L-gasket is secured by a Cable Strap (E). The ¼" vacuum hose with PTFE O-rings secure the hose to the vacuum chamber and to the internal vacuum port in the microwave cavity.

Optional Top Plate with Temperature Probe Port for Vacuum Chamber also available. Supplied with two caps—one solid and one with opening for temperature probe.

Installation and Use of Vacuum Chamber: The appropriate installation of the vacuum chamber is shown below. See Figure 2. The recommended vacuum level is 20” of Hg (508 Torr). The PELCO BioWave® series of microwaves have a preset vacuum to this level along with a venting feature within the protocols. Vacuum grease is not required for the operation of this chamber. Always make certain the top is seated correctly when the vacuum is initiated. The PELCO® EM Pro Vacuum Chamber is recommended for assisting in chemical fixation and resin infiltration. Any other applications should be carefully researched and tested prior to incorporation into a protocol.

Figure 2. Installation

WARNING: The use of vacuum with solvents is not recommended. For processing steps where water is present, temperature restrictions below 70° must be used. For processing steps where formalin is present, temperature restrictions below 40° must be used. Liquids with these characteristics will boil and be drawn into the vacuum system and severely damage the components of the microwave.

Instructions for replacing cable strap for L-gasket: Place L-gasket on vacuum chamber by stretching the gasket past the edge and gently “walking” the gasket around the edge of the chamber. Once the gasket is in place, place the cable strap over the gasket and thread through the lock. See Figure 3. Use a pair of needle nose pliers and grip the end of the strap. Turn the pliers as if you are rolling the excess strap. Continue this motion until the cable strap is tight around the gasket and chamber. See Figure 4. Cut off the excess strap. See Figure 5. Use a file to smooth off the cut end at the lock. See Figure 6.