When designing utility networks, developing kitchen projects, or simply trying to understand the technical documentation of a household appliance, the user is often faced with the need to identify equipment. Refrigeration equipment in the drawings is not drawn realistically, but is replaced by conventional graphic symbols that are understandable to specialists. The ability to “read” these symbols is critical for correct calculations of loads, laying communications and subsequent maintenance of equipment.
There are several coding systems, depending on the type of circuit: electrical circuit, installation or architectural layout. In each case, refrigerator designation will be different in essence, although visual similarities can be traced. Electricians use alphanumeric codes, and kitchen designers use geometric figures with callout dimensions.
Understanding these differences allows you to avoid costly mistakes when purchasing equipment or laying power cables. If you confuse the symbol of the hob and the refrigeration unit on the electrical diagram, this can lead to an emergency or the inability to operate the equipment. Therefore, it is important to clearly distinguish the context in which this or that symbol is used.
Standards of graphic symbols according to GOST
In professional documentation in the Russian Federation and CIS countries, the main document regulating the rules for drawing up drawings is GOST 21.205-93 (SPDS). This standard defines the symbols of elements of sanitary systems, however, for household appliances, adapted standards from related sections concerning electrical equipment are often used. On architectural plans, the refrigerator is most often depicted as a rectangle with a rounded corner or a double line imitating doors.
It is important to consider that on water supply diagrams, if the refrigerator is equipped with a water supply system (Ice & Water), it can be marked as a water-folding device with an appropriate connection to the main line. Electrical circuits are based on GOST 2.755-87, where attention is paid to switching devices. The refrigerator itself appears here as a load connected to the network through an outlet or circuit breaker.
To specify equipment in the explication tables, a letter code is used. Most often you can find the abbreviation XSh (refrigerator-cabinet) or HC (refrigerator-chamber). In restaurant and cafe projects, where documentation requirements are stricter, each unit receives a unique number corresponding to the specification, for example, X-01, X-02.
- 🔲 Rectangle with two doors - a standard image on floor plans.
- ⚡ A circle with the letter "M" inside - the designation of a compressor on electrical diagrams.
- 💧 A drop or tap - the presence of a water supply system (relevant for Side-by-Side).
- 🌡️ Thermometer - symbol a thermostat or temperature sensor in the control circuit.
⚠️ Attention: On evacuation plans and fire diagrams, household refrigerators are often not displayed at all if they are not part of stationary fire extinguishing or ventilation systems. Do not look for them on escape route diagrams.
Electrical diagrams and letter codes
When it comes to connecting equipment, electrical circuit diagrams come to the fore. Here refrigerator is considered as an electric motor (compressor) with a control system and heating elements (defrost heating elements). Unlike architectural plans, current characteristics and type of protection are important here. The main element - the compressor - in old diagrams could be designated simply as an engine, but modern drawings require detail.
The letter designation in specifications and diagrams is often based on international standards or internal regulations of the manufacturer. However, in general residential electrical projects, a refrigerator is classified as a household appliance. It is characterized by the use of a rosette group. On the single-line diagrams of the panel you will see an socket icon indicating the power, for example, 2.2 kW, which indirectly indicates the possibility of connecting refrigeration equipment.
Particular attention should be paid to the controls. On automation circuits (for example, for industrial cameras or smart refrigerators) there are sensor codes. The thermal relay is designated as SK, the starting relay is designated as K. Understanding these symbols is necessary when diagnosing faults using the service manual. If in the diagram you see an open circuit with a bimetallic plate symbol, we are talking about a protective thermostat.
When reading electrical documentation, it is important to distinguish between the power part and the control circuit. The power section includes the phase, neutral and ground supply to the compressor. The control circuit is the “brains” of the device, including an indication module, sensors and relays. Errors in reading these symbols can lead to incorrect diagnosis of the breakdown.
What do the codes on the tag inside the refrigerator mean?
The internal tag (nameplate) always indicates the rated power and current. This data is critical for selecting the cable cross-section. If the diagram shows a 16A circuit breaker, and the total current of the devices exceeds this limit, the protection will work. Always check the diagram data with the actual tag of the device.
Symbolism on installation and architectural plans
Architectural plans are created to visualize the space, therefore here refrigerator designation it is as close as possible to its real geometry, but simplified. Usually this is a rectangle, inscribed in the contour of the kitchen unit or standing alone. The most important aspect here is the indication of overall dimensions and door opening zones. The designer must provide space for ventilation and maintenance.
On furniture layout plans, the refrigerator is often shaded or painted over to differentiate it from the cabinets. If built-in appliances are used, only the façade of the furniture is indicated, and the unit itself can be hidden behind a conventional line. For built-in models Liebherr or Bosch it is critical to indicate the type of ventilation, as this affects the gaps left in the project.
Utility networks suitable for the installation site are also marked in a special way. If the refrigerator requires connection to a water supply, the water point will be visible on the floor or ceiling plan. Its symbol is different from a regular sink. A callout with a text explanation is often used, for example: “Connecting a refrigerator with an ice maker.”
- 📐 Exact dimensions - width and depth are indicated in millimeters directly on the drawing.
- 🚪 Opening direction - an arc arrow shows the trajectory of the door.
- 🔌 Power supply point - a circle with two or three risks, located at a height of 90-100 cm from the floor.
- 💨 Ventilation gap - a dotted line showing the required distance to the wall.
⚠️ Attention: On installation plans they often forget to indicate “dead zones” for door hinges. Make sure that in the diagram the refrigerator is positioned so that its door is not blocked by adjacent furniture or the corner of the wall when opening 90 degrees.
Deciphering elements on electrical circuit diagrams
For a deep understanding of the operation of the device, you must be able to read a circuit diagram (PES). Here refrigerator appears as a set of electrical components. The central place is occupied by the compressor, which is indicated by a circle with the letter M (Motor) or a specific symbol of the piston mechanism. Its power in watts or kilowatts is always indicated next to it.
The defrost system is the second most important unit. In the diagrams it is represented by a heating element (heating element), which graphically looks like a zigzag line inside a rectangle or oval. The defrost relay and timer (or electronic control module) are connected to the heating element by lines indicating electrical connections. Understanding this chain helps diagnose ice problems.
Lights and fans are identified by standard electrical symbols. The lamp is a circle with a cross inside, the fan is a circle with a letter M and an impeller. All these elements are combined into a single network, protected by fuses or thermostats. An open in the thermostat circuit is indicated by a temperature-dependent breaker symbol.
The following is a table of the main symbols found in service documentation:
| Element | Graphic symbol | Alphabetic code | Function |
|---|---|---|---|
| Compressor | Circle with M | KM / M | Refrigerant compression |
| Thermostat | Breaker with thermometer | SK / TS | Temperature adjustment |
| Defrosting heating element | Zigzag in the oval | R / EH | Heating for defrosting |
| Start relay | Coil with contact | K | Engine start |
| Light lamp | Circle with a cross | EL | Backlight cameras |
Specific designations for built-in equipment
Built-in refrigerators have their own specific designations on the diagrams, since they are part furniture constructive. In kitchen drawings, such a unit often does not have its own contour, but fits into the dimensions of the column cabinet. It is important to pay attention to the symbols indicating the type of facade: full facade (covers the entire door) or partial (overlay panel).
In the technical documentation for built-in models Siemens or Whirlpool you can find special markings of attachment points. On assembly diagrams they are indicated by crosses or dots with extension dimensions. This is necessary for the correct positioning of the brackets holding the heavy unit inside the niche.
A special requirement for built-in appliances is ventilation. Diagrams of kitchen units must include designations of ventilation grilles in the base or cornice. Without them refrigerator it will work with overheating. The grid symbol (mesh) in the drawing indicates the mandatory presence of a hole for air circulation.
☑️ Checking the installation diagram
Reading diagrams for industrial refrigeration chambers
Industrial refrigerators and freezers are complex engineering structures, and their diagrams differ significantly from household ones. Here refrigerator designation is replaced by a refrigeration unit circuit, including a compressor-condensing unit (CCU) and an air cooler. On the plans of workshops or warehouses, these are large objects, often placed outside the premises (on the roof or street).
On process diagrams (P&ID), each pipeline element, valve and sensor has its own unique tag. The refrigerator compartment is designated as a room with a certain temperature regime, for example +2...+6 °C. The walls of such a chamber are lined in a special way, indicating thermal insulation. The doors are equipped with symbols of hermetic seals.
Industrial refrigerator automation systems include dozens of sensors. On control diagrams they are located around the perimeter of the camera and inside it. It is important to distinguish between air temperature sensors and product temperature sensors. Errors in reading these symbols can lead to damage to goods in the warehouse.
⚠️ Attention: Industrial diagrams often contain symbols of refrigerant (freon, ammonia) indicating the direction of flow with arrows. Never confuse suction and discharge lines - they have different pressures and temperatures, which is critical for personnel safety.
Frequently asked questions (FAQ)
What standard symbol is used for a refrigerator on an apartment plan?
Most often, a rectangle with a rounded corner is used, imitating a door. Overall dimensions may be indicated inside or nearby. In electrical projects - a socket icon with the caption “Refrigerator” or “Household Appliances.”
What does the letter “M” mean in a circle on the diagram of a refrigerator?
This symbol denotes an electric motor, in this context a motor-compressor, which is the heart of the refrigeration machine and ensures the circulation of the refrigerant.
Is it necessary to indicate the refrigerator on the wiring diagram?
Yes, this is necessary to calculate the total load on the network. A refrigerator belongs to devices with continuous operation, and it is often recommended to allocate a separate line for it or take it into account in a kitchen group with a power reserve.
What is the difference between the designation of a built-in refrigerator and a freestanding one?
On architectural plans, a built-in refrigerator fits into the contour of a furniture cabinet and may not have its own external contour, unlike a freestanding one, which is drawn as an independent object with gaps for ventilation.