- The device and principle of operation of cassette splits
- Features of cassette air conditioners
- Choosing a cassette split system
- At the end
In this article: how cassette splits work and work; do not like the blocks of split systems that are in plain sight – put the cassette holder in the suspended ceiling; pros and cons of a cassette air conditioner; three models of cassette split systems – choose one; the service life of the cassette depends on its preventive maintenance.
False (suspended) ceilings are popular and widespread both in private offices and in administrative institutions. Suspended ceilings, if viewed from the perspective of climatic equipment, have one drawback – they hide the upper part of the walls, which makes it difficult to place hair dryers from conventional split systems. To solve this problem, the manufacturers of split systems have created a specialized class of air conditioners called “cassette”.
The device and principle of operation of cassette splits
Cassette air conditioners consist of two units – external and internal, connected by a freon line made of copper pipes. The external unit is arranged in the same way as the street units of split systems of other classes, the compressor units of the cassette units differ from each other mainly only in terms of power and type of compressor.
The cassette split indoor units have a shape and size suitable for installation in a suspended ceiling section – models are produced in square (width from 570 to 840 mm) and rectangular, supplying treated air from one to four directions, having a cooling capacity of 2.1 to 16 kW. Unlike other split systems, the arrangement of the units in the inner block of the cassette is different – there is a centrifugal fan in the center of the case, and the tubes of the heat exchanger-evaporator are extended along the perimeter of the inner walls.
Air from the room is pumped into the air conditioner by a ventilation unit, when it comes in, it is cleaned from dust, then sent to the heat exchangers. The temperature and humidity of the air when passing through the tubes of the heat exchangers decrease, the cooled air enters the room through the side louvers, and the condensate is collected in the storage tank. Since the removal of condensed liquid from the indoor unit by gravity is not possible due to its design, each block-hair dryer is equipped with a pump pump that pumps condensate through drain pipes to the sewer or to the street.
The louvers of the multi-stream cassette units are independently controlled, i.e. you can completely close the blinds on one side of the hair dryer, leaving them open on the other sides, or give the shutters a different opening position. Single-lane cassette splits are used in rectangular rooms – such a unit is usually built into a suspended ceiling in a section near the wall.
Compared to other classes of split systems, the case of the cassette hair dryer is completely hidden behind the plane of the suspended ceiling, only the air intake grille and the decorative panel with air supply louvers come out. The installation of the cassette unit is carried out using a mounting kit, regardless of the suspension system of the suspended ceiling, its weight will not affect the strength of such ceilings. The exact distance of the ceiling from the floor, at which a cassette split system can be installed, depends on the specific model of the device..
Internal cassette air conditioners are sold in the retail network both complete with an external unit and without it – the second option is designed to integrate a hairdryer into a multisplit system.
Features of cassette air conditioners
The cassette split has two most important advantages inherent only to it – a hidden installation and the presence of several directions of air supply. The cassette body hides 90% of the under-ceiling space formed by the suspended ceiling; only the air intake and side louvers that supply the prepared air are visible from the outside. The decorative panel covering the body of the indoor unit is made in various styles, which allows the use of cassette air conditioners in rooms with any decor.
Unidirectional cold air flow, traditional for split systems of different classes, is completely excluded in the case of a cassette air conditioner (except for models with a single-flow air supply) – the processed air entering the device and returning to the room in several directions, uniformly cooling or heating the atmosphere in it, without causing while drafts.
Cassette air conditioning units are effective when used in rooms ranging from 20 to 150 m2 – in a short time, the criteria of the air atmosphere are changed to the level specified by the user, their work is accompanied by a low noise level. Some models of cassette units are capable of mixing fresh air into the internal air volume of the room (no more than 10% of the total volume of processed air), in the case of inverter control, they economically consume electrical energy. Easy control and setting of parameters using the remote control, work in several modes.
Cons of cassette players:
- their installation requires space in the under-ceiling space under the false ceiling – on average 250-280 mm, otherwise the indoor unit will not fit;
- limitation on the height of ceilings (not suspended) – at least 215–420 mm, depending on the split power;
- in case of a malfunction of the pump that pumps out condensate, the air conditioner will not work;
- the produced models belong to the middle and high price segments, i.e. prices for them start at 30,000 rubles. and higher.
Choosing a cassette split system
The cost, power, brand and attractiveness of the decorative panel of the cassette are not decisive in their choice – these are only some of the criteria that the buyer must take into account. Using the example of three arbitrarily selected models of cassette splits, we will illustrate how to choose the right one climatic device from a wide range on the market.
|specifications||UT12NRDR0 / UU12ULDR0, UT series, LG|| KSZR35HFAN1 / KSUN35HFAN1,
|MCA2-12HRN1-Q / MOU-12HN1-Q, Midea|
|power supply and power consumption|
|power consumption for cooling, kW||1.29||1.08||1.09|
|power consumption for heating, kW||1.32||1.24||1.24|
|energy efficiency ratio EER / COP (cooling / heating)||2.62 / 2.84||2.95 / 3.24||2.95 / 3.24|
|maximum serviced area, m2||thirty||thirty||thirty|
|outdoor temperature range for cooling, ° С||from +11 to +43||from +18 to +43||from +18 to +43|
|range of outdoor temperatures for heating, ° С||to -7||to -7||to -7|
|cold performance, kW||3.3||3.52||3.5|
|heat capacity, kW||3.75||3.81||3.8|
|maximum air flow for cooling, m3/ h||570||570||680|
|maximum air flow for heating, m3/ h||570||570||680|
|elimination of moisture, l / h||not installed||not installed||not installed|
|indoor unit noise level min / max, dB||32/38||35/41||35/41|
|outdoor unit noise level, dB||47||44||43|
|operating modes, name||cooling, dehumidification, ventilation, heating||cooling, dehumidification, ventilation, heating||cooling, dehumidification, ventilation, heating|
|type of ventilation unit||centrifugal||centrifugal||centrifugal|
|number of fan speeds||3||3||3|
|wired remote control *||+||+||additional option|
|infrared remote control||additional option||additional option||+|
|auto regulation of air supply||+||+||+|
|number of fixed positions of air louvers||2||2||2|
|stirring mode (swing blinds)||+||+||+|
|blinds control **||pairwise||four blinds at the same time||four blinds at the same time|
|automatic system diagnostics||+||+||+|
|type of shell||horizontal monoblock||horizontal monoblock||horizontal monoblock|
|body material||metal, plastic||metal, plastic||metal, plastic|
|type of instalation||ceiling||ceiling||ceiling|
|type of refrigerant||R410A||R410A||R410A|
|maximum length of the freon line, m||15||15||15|
|maximum height difference between blocks, m||ten||8||8|
|ceiling height in the installation room min / max, m||2.8 / 4.2||2.8 / 3.5||2.8 / 3.5|
|minimum height of the ceiling space, cm||26||25||25|
|head of drainage pump head, mm ***||700||350||500|
|types of special filters|| antibacterial
|number of air flows (blinds groups), pcs.||4||4||4|
|air louver adjustment||vertically and horizontally||vertically and horizontally||vertically and horizontally|
|anti-corrosion protection of the housing from the inside||+||+||+|
|the ability to work at any time of the year||not in the RF climate||not in the RF climate||not in the RF climate|
|possibility of mixing external air||–||–||+|
|operation in exhaust ventilation mode||–||–||–|
|mounting kit for outdoor unit||additional option||additional option||additional option|
|the size of the indoor unit HxWxD, cm||57×26.9×57||57x26x57||57x26x57|
|size of the external block HxWxD, cm||54x77x24.5||54.7x78x25||54.7x78x25|
|weight indoor / outdoor unit, kg||19/32||15.6 / 28||21/37|
|decorative cover panel||additional option||additional option||additional option|
|dimensions of the decorative cover panel (HxWxD), cm||67x67x3||64.7×64.7×5||64,7х64,7х3|
|weight decorative cover panel, kg||3||2.5||not installed|
|brand owner||LG Electronics, South Korea||Kentatsu Denki ltd, Japan||Midea Holding Co., China|
|country of origin||China||China||China|
|estimated service life, years||ten||ten||ten|
|average cost, rub.|
(*) – a wired remote control means a wall-mounted (i.e. stationary) remote control connected to the cassette unit with a wire.
(**) – the blinds are controlled by small electric motors, the number of which determines the possibility of independent control of the air supply from each side. For example, you can completely close one blinds, leaving the three remaining ones open, if each of them is controlled by a separate electric motor, if there is only one such electric motor, then all the blinds will be controlled by it simultaneously and set to the same position.
(***) – the height to which the drainage pump is able to lift liquid from the storage tank. The higher the backwater level, the higher the height of the drainage hose.
UT12NRDR0 / UU12ULDR0, UT series, LG
Data on three cassette splits are summarized in a table – let’s examine them:
- energy consumption for cooling and heating a room in the LG model is higher than that of the other two cassettes, which significantly reduces its energy efficiency. Interestingly, the EER and COP coefficients of the considered Kentatsu and Midea cassette air conditioners coincide;
- all three splits are capable of heating a room at an outdoor temperature of at least -7 ° C – when it reaches and further drops in temperature, the devices will automatically turn off;
- the smallest range of noise during operation – at the LG cassette;
- A Midea air conditioner drives a larger volume of air through its indoor unit per unit of time than other splits. Most likely, this is due not to the higher capacity of the ventilation unit, but to the absence of a fine air filter, which is not included in the package of this model even as an additional option;
- LG and Kentatsu cassettes are equipped with a wired remote control as standard, a portable remote control is an additional option. The Midea split has the opposite situation – an infrared remote control is included in the standard package, and the stationary one is optional;
- LG indoor unit, according to the technical data, can be installed at a higher height than the other two models. However, its cooling and heating capacity is lower compared to Kentatsu and Midea devices, so this statement looks rather controversial;
- the advantage of the LG cassette is in the pairwise control of the air supplying louvers, which is unacceptable for Midea and Kentatsu splits;
- only the Midea cassette split allows the addition of fresh air from the street to the serviced room, but to implement it, a special tube must be pulled to the indoor unit, with the other end extending beyond the outer wall of the building;
- decorative trim panels on the three air conditioners reviewed are not standard equipment. The main reason is the different needs of buyers in the field of colors and designs of these panels. By the way, the cost of overhead panels will be about 3,500 rubles;
- for the rest of the technical characteristics, the considered cassette split systems are the same or close;
- the terms of warranty and approximate service for the considered splits are the same, at the average cost the cheapest model is the Midea brand, the most expensive is the LG model.
KSZR35HFAN1 / KSUN35HFAN1, Kentatsu
Conclusion: having studied the characteristics and capabilities of three cassette split systems, I recognize the most profitable purchase of the MCA2-12HRN1-Q / MOU-12HN1-Q two-unit air conditioner, manufactured by the Chinese company Midea Holding Co.
MCA2-12HRN1-Q / MOU-12HN1-Q, Midea
The reasons for this decision: two other manufacturers also assemble their HVAC equipment at Chinese factories, so there is no particular difference in assembly quality; I am more satisfied with the infrared remote control than the stationary one, and it comes standard with the Midea cassette player; the cost of the device is lower than that of the LG and Kentatsu models; the air conditioner is designed to mix fresh air; laying a flexible air duct to implement this feature will not be difficult and will not result in high costs. Midea’s lack of a fine filter, even in an additional option, is unpleasant, but, given the standard dimensions of the indoor unit, it will most likely be possible to install a filter from other manufacturers in its indoor hairdryer.
At the end
When planning the purchase and installation of a cassette split system, it is necessary to take into account the need for annual preventive maintenance on it, otherwise the device will fail much earlier than the manufacturers promise. By the way, prevention means not only flushing the air filter (in fact, it needs to be cleaned at least once every two to three weeks), cleaning the louvers from dust and pumping a certain brand of freon, but also the obligatory flushing of the blocks with water under pressure. However, it is undesirable to remove the block-hair dryer for flushing, therefore it is important to provide the service employees with free space under the block, and they will be responsible for the non-proliferation of dirt outside this area..
Column split systems rise in offices and sales areas like the antique columns of Greece, while they do not support the vaults of the premises, but maintain the atmosphere in them – the next article, you guessed it, will be devoted to this particular class of air conditioners.