Garland CG-24, CG-36, CG-48, CG-72, CG-60 Servicing, Thermostat, How To Replace a Thermocouple

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SERVICING continued

Thermostat

Make sure the thermostat knob is correctly aligned with the dial indicator.. To align the knob with the graduated dial correctly, follow this procedure..

1.Turn the knob and shaft fully counter-clockwise.. Loosen the set screw in the knob and align the pointer with the first line of the scale at the lower left position..

NOTE : When the knob is fully rotated clockwise, the pointer should align with the last line of the scale..

2.Set the dial to 350˚F.. Wait at least three cycles before monitoring the temperature..

3.Use a surface temperature probe disc positioned on the center line with the thermostat knob and centered front to back on the griddle plate..

The thermostat will overshoot and undershoot as caused by the lag time in the thermal response of the heat source- to-plate and plate-to-sensor.. The calibration temperature will be the mid-point between the minimum and maximum readings.. Other than the alignment of the knob pointer, there is no means to calibrate the thermostat.. It has been precisely calibrated by the manufacturer..

Thermocouple

If the temperature is incorrect check the thermocouple.. The thermocouple in this unit is a Type J, which requires the use of a J-type temperature meter for checking.. For a complete understanding of the thermocouple used in the chain griddle see the GCR Service Bulletin #95-5 entitled “Thermocouples”..

A thermocouple is an accurate temperature measuring device that consists of two dissimilar conductors joined together at their ends.. It works on a simple principle, which is that the thermoelectric voltage between the two junctions is proportional to the temperature difference between them.. This principle is applied to measure the temperature at one of the junctions when the other is held at a fixed known temperature.. The technology is not new, but its use in GCR griddles is recent..

The thermocouple probe is embedded in the griddle plate and accurately registers the surface temperature.. It is a reliable device, but can cause problems when it fails for any reason.. In addition to deterioration from aging, it can fail in two ways: one from an open-circuit (that is, a break in one of its wired); the other when it short-circuits..

If a thermocouple open circuits, the thermostat will shut off and prevent the gas valve from opening, which means the burner will not function..

If a unit short circuits somewhere behind the junction, it creates a new junction and because the circuit cannot detect the existence of a short circuit fault, there is a dramatic increase in temperature.. The thermocouple detects changes in temperature, but because of the short circuit it may fail to register the set temperature at the thermostat.. This means the burner may not shut off.. At the other extreme, the short circuit may occur in a place not shielded from the flue gases, which means the burner may shut off prematurely.. These are the two conditions to look for in a shorted thermocouple..

Deterioration from aging and from welding dissimilar metals together to for a junction introduces a contaminant that causes mechanical stress.. Over time, five to ten years, metal fatigue from aging is certain.. As a result, the temperature curve will vary..

How To Replace A Thermocouple

A heat shield protects the thermocouple from the burner flames and flue gases.. Without the shield, the thermocouple would register flame heat to the thermostat instead of sensing the temperature of the griddle plate..

To replace a thermocouple (refer to Figure 3), following this procedure:

1.Open the front panel to get access to the terminal board..

2.To withdraw the thermocouple, first remove the heat shield.. It is held in place by two combination Philip and Robinson-heat size number 10 sheet metal screws.. Remove the heat shield by sliding it down the wire..

3.A bayonet connector secures the thermocouple in place.. Reach inside the hole and push and twist the bayonet connector a quarter turn..

4.Remove the connection to the terminal board and feed these wires through the heat shield.. The thermocouple is now removed..

5.Connect the wires of the replacement thermocouple, but make sure the polarity is correct.. Connect the negative red wires to terminal 7 on the thermostat and the positive white wire to terminal 8.. (See schematic diagram)..

6.Thread the thermocouple through the heat shield and into the plate cavity..

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Part #GCGTRAINING06 (03/03/08))

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Contents Garland GAS Important Information Keep appliance area free and clear of combustiblesTable of Contents Dimensions and Specifications Back NaturalWhat is a Chain Griddle How Does it work?Mechanical What is a Chain GriddleInstallation Gas SupplyVentilation InstallationElectrical Power, Lighting & Control Start-UpOperation & Maintenance CleaningServicing Thermostat How To Replace a ThermocoupleServicing ThermocoupleIncandescent Lamps Pilot Ignition Control Control ModuleGas Valve Regulator Power SwitchesControl Circuit Control Panel Schematic Diagram Control schematic for a Model CG-48 Chain GriddleService Bulletin #95-5 SubjectService Bulletin #95-5 Type J Thermocouples 0 to 440F EMF In Millivolts Reference Junction 0FType J Thermocouples 0 to 240C EMF In Millivolts Reference Junction 0CGCGTRAINING06 03/03/08 GCGTRAINING06 03/03/08

CG-60, CG-72, CG-48, CG-36, CG-24 specifications

The Garland CG series is renowned for its dependable and innovative design, catering to diverse needs in commercial kitchens. The series includes models CG-24, CG-72, CG-48, CG-60, and CG-36, each with unique features that make them suitable for various culinary tasks.

Starting with the CG-24, this compact unit is designed for restaurants with limited space but a high demand for efficiency. The CG-24 offers a single deck oven with a capability to yield remarkable results without compromising on quality. Its adjustable temperature settings allow for precision cooking, while the stainless steel exterior ensures durability and easy maintenance. The commercial-grade heating elements provide consistent heat distribution, making it ideal for baking and roasting.

Next is the CG-72, a larger model designed for high-volume operations. The CG-72 boasts a double-deck construction, allowing chefs to prepare multiple dishes simultaneously. Its advanced convection technology circulates hot air evenly throughout the oven, enhancing cooking efficiency. This model also features programmable digital controls, giving chefs the ability to save and replicate cooking profiles with ease, ensuring consistency across multiple dishes.

The CG-48 is tailored for versatility, featuring multiple cooking options that include baking, broiling, and warming. Its spacious interior can accommodate various tray sizes, making it a favorite amongst bakers and caterers. With user-friendly controls and high-performance heating systems, the CG-48 ensures that food is cooked to perfection every time. Additionally, its efficient energy usage makes it a cost-effective choice for businesses seeking to reduce operating expenses.

Moving on to the CG-60, this model integrates cutting-edge technologies to enhance sanitation and ease of use. The CG-60’s self-cleaning feature significantly reduces labor and time spent on maintenance, while its robust construction ensures longevity under heavy use. The digital interface allows for precise control over cooking times and temperatures, making it a reliable partner in busy kitchen environments.

Finally, the CG-36 offers a balance of size and power, making it ideal for medium-sized operations. Its range of cooking options alongside efficient heat distribution makes it a versatile choice for chefs. The compact design does not sacrifice performance, ensuring that even small footprints can accommodate high culinary output.

In summary, the Garland CG series combines advanced technology with practical design, ensuring that each model—CG-24, CG-72, CG-48, CG-60, and CG-36—meets the diverse needs of commercial kitchens, delivering exceptional performance, durability, and user-friendly operation.