Master Bilt GT-40, GT-30 manual Automatic Expansion Value Gt Series Cabinets, Cleaning

Models: GT-40 GT-30

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AUTOMATIC EXPANSION VALUE GT SERIES CABINETS

AUTOMATIC EXPANSION VALUE GT SERIES CABINETS

After the cabinet has been in operation for a short time the high pressure or discharge pressure of the refrigeration system should be 250 pisg to 270 pisg in a 75 oF ambient room. The suction pressure at the compressor should be approximately 7 to 9 pisg *** . The cabinet does not have to be at operation temperatures for the pressures to stabilize. The automatic expansion valves are basically preset and should not need any adjustment for proper operation. If the system pressures are not correct and the valve does need adjusting be aware that IN THE WORST CASE ONLY A VERY SMALL ADJUSTMENT MAY BE REQUIRED. To increase the valve outlet pressure and thereby increase the suction pressure the adjusting screw is turned in a clockwise direction as the valve is viewed with the adjusting screw pointed up. Be sure to replace the red plastic cap covering the valve adjustment screw. After the pressure is set it SHOULD NOT TEND TO CHANGE after additional run time or as the cabinet temperature changes. The sight glass, if install, may not appear to be completely full. This is a normal condition. DO NOT INCREASE the refrigerant charge quantity above the listed charge because the sight glass does not show full.

***Units used for boxed candy display should have the expansion valve adjusted to deliver 12 to 14psig at compressor suction port, this pressure is not suitable for ice-cream.

REFRIGERATION SYSTEM AND OPERATION

The cabinet utilizes a Copeland Copelametric compressor and operates with refrigerant 404A. Cabinet operates on 115/60/1 power. The cabinet has a bare tube type condenser, which virtually eliminates the possibility of condenser blockage by dust and dirt.

The cabinet operates with a specific charge of refrigerant 404A. The amount of the charge of refrigerant is listed on the cabinet nameplate in ounces. These systems use an automatic expansion valve to meter refrigerant to the evaporator. They include automatic electric defrost systems which are time initiated (by the time clock) and terminated by a defrost termination thermostat which is mounted on a coil supporting bracket in the gravity coil section directly beneath the top of the cabinet. This defrost termination overrides the time clock and turns the compressor back on line when the gravity coil is defrosted. This is the point at which the coil has reached sufficient temperature to insure complete defrost. If the defrost termination control should fail to operate, the time clock will automatically turn off defrost and again turn on the compressor after the 34 minute (or the time interval you selected) interval set on the time clock. If the time clock fails to turn the heaters off, a final back-up safety thermostat will shut off the heaters when gravity coil temperature reaches +80 oF.

Cabinet has a refrigeration system known as automatic defrost gravity coil with cold wall construction. This means the inner liner of the cabinet below the load level line is refrigerated by gravity flow of air from a fin and tube coil, as well as copper refrigerant lines attached to the back of the inner liner tank on all sides and the bottom.

CLEANING

WARNING: DO NOT REMOVE FROST WITH A KNIFE, PICK, OR SHARP OBJECTS. DO NOT USE ABRASIVE CLEANERS OR CAUSTIC CLEANERS OR SCOURING PADS

Every 30 to 60 days (depending on frost accumulation), the cabinet should be emptied, warmed up, and wiped down using a solution of 1 teaspoon of baking soda with 1 quart of water. This solution will help eliminate odors. Do not use strong soaps or detergents as they leave odors that can contaminate your product. The GT line cabinets are equipped with a floor drain that exits out the lower rear of the cabinet. This exit has a convenient garden hose fitting.

If it is not convenient to turn the power off the cabinet, lay a piece of plastic sheeting on the floor of the cabinet and scrape the frost off walls using a plastic scraper. Do not use metal scrapers. This will damage the interior paint of the cabinet.

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Master Bilt GT-40, GT-30 manual Automatic Expansion Value Gt Series Cabinets, Refrigeration System And Operation, Cleaning