Installation Guidelines for Holdover Plates

When choosing the proper plate sizes, primary consideration should be given to calculated BTU loads as well as box design and usage. Any special requirements must be determined prior to selection and installation.

Holdover plates are available with 26°F(-3°C) eutetic solution for refrigerator box applications, and 0°F(-18°C),-9°F(-23°C) and -18°F(-28°C) solutions for freezer box applcations. The freezer plates are identified with 1,2 or 3 (for the 0, -9 and -18°F plates respectively) V-notches located on the mounting flange at the the same end as the refrigerant line connections. The 26°F plates have no notch in the flange on the opposite end.

The Grunert line of holdover plates is designed to be installed in any to be installed in any position on a box's interior surface, or as a shelf accross the interior space. Each plate has mounting flanges, across both short ends (smaller dimension) with 1/4" diameter mounting holes. Secure the plate(s) with the proper fasteners (lag screws, thru-wall connectors, etc.) to support the weight and torsion load from the vessel's movement.

Plates must be mounted with stand-ffs to expose the back surface area of the plate to provide porper performance. A minimum of 5/8" (1.6cm) clearance between the box and black of the plate is recommended.

Expansion valves must be located and fastened properly. Do not install expansion valves with the diaphram on the bottom. Recommended location of the valve is in the box(es) with the plate. The expansion valve sensing bulbs are to be properly located and secured on the outlet (suction line) of the last plate in series. Recommended location is on a horizontal portion of tubing on the top(between twn and twelve o'clock). If either the expansion valve ot its sensing bulb must be locates outside of the box, each part must be properly insulated to protect against condensation, as well as to allow temperature sensing of the bulb.

Thermostat sensing bulbs are to be inserted into the sensing wells located on the holdover plate. Two sets of wells are located on two sides of each plate. Once a plate has been positioned in a box, the well(s) that are located on the side(vertical surface) should be used for the most accurate sensing of plate temperature.

• 3‡ Example : A 0° freezer box with inside dimensions of 24" height, 12" depth and 18" width has an internal volume of 5184 cubic inches (24 x 12 x 18). Divide the 5184 cubic inches by 1728 (one cubic foot) to get three cubic feet. With 4" of insulation, a 2700 BTU leak is found from the chart. Referring to the 0° Freezer Capacity (BTUs) row on the front of this sheet, two 16 x 10 plates (3072 BTUs) or one 24 x 13 plate (3118 BTUs) may be used.
• * TO CONVERT CUBIC FEET, MULTIPLY BY 35.31.
• ** CHART IS DESIGNED USING POLY FOAM WITH A TWO POUND DENSITY RATING.