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Chillers or also known as refrigeration machines are widely used in many industries. Their main function is to remove heat in order to maintain comfortable temperature within the rooms. Nowadays, there are many types of chillers used for various purposes. Costs for installation of such system and its further operation are pretty high. It is also obvious that the customer is interested in its stable and uninterruptible work. What are the common issues owners of buildings with chillers installed face and how can they be avoided? Issue: Unstable operation of chiller Cause: Partial load Power calculation for determining cooling capacity is normally carried out taking into account the highest air temperature in the summer. Such high temperatures are irrelevant during the day as the air temperature drops at nights and on cooler days. Therefore, generation of the cold for a building in relation to temperature fluctuations at different times of the day and under various weather conditions is generally higher than it is necessary. In this case we can see partial loading of the chiller. It further results in its decreased efficiency in general. It should also be noted that type of compressor used and the type of capacity regulation are important for efficiency. There might be another problem when loading on cooling system at a certain time is below the minimum values of cooling capacity of chiller itself. In this case, we may see cyclic switching off and on and it also affects efficiency of the system. This often becomes the main reason of failure of automatic control system because it wears it out. As a result, you will face increased operating and maintenance costs of the chiller. It is extremely expensive for the owner of facilities. Resolution of the issue In this case, it is advisable to install two chillers with different or identical capacities. At the same time, it is necessary to select equipment according to its capacity and considering the needs of the building in cooling throughout the year. At this point, the first chiller will have high efficiency refrigeration with most typical loads over a long period of time. The second chiller will generate additional cold during peak loads. Efficient operation of the cooling system under this approach will require correct calculation of building’s need in cold throughout the year. When calculating, it is necessary to take into account the following factors: heat generation variables within the building, changes in the air temperature outside, temperature of cooling water that circulates in the system, load of building, etc. Issue: Defrosting and damage to heat exchanger of the chiller Cause: Not appropriate maintenance of equipment Heat exchanger is one of the key components of the chiller. Working fluids of the system constantly run through its channels. Leakage between circuits of heat exchanger is one of the most common failures. Untimely or incompetent maintenance of the chiller may cause defrosting and damage to heat exchanger and chiller. When micro leakage occurs, water enters refrigeration circuit that results in irreparable damage for the compressor. After a while, refrigeration compressor will be completely flooded and the chiller fails to operate. Resolution of the issue It is important to take preventive measures for safety of the equipment and mechanisms of the chiller. Professional preservation of the system for winter period will be needed in this case. To do this, it is necessary to stop the chiller. If it is water based coolant, drain it completely from the heat exchanger and pipelines. After draining water from heat exchanger (especially true for plate type), pour antifreeze into it for the winter storage period as remains of even a small amount of water would expanding during crystallization may damage evaporator and refrigeration machine. As we can see, “pennyworth” but timely measure will allow you maintain your equipment in good condition and avoid unnecessary high costs. Most of malfunctions that result in the failure of the heat exchanger and compressor, shutdown of the chiller and costly repairs, may be identified and solved at the very initial stages. ARTS specialists perform both installation/repair of chiller equipment and carry out complex diagnostics of systems. Scheduled diagnostics is recommended at intervals of at least once a year for efficient operation of the chiller. TOP mistakes when choosing your chiller Specialists of companies that perform servicing HVAC equipment very often have to correct errors that customers made themselves when choosing and installing their chillers. We have collected the most common ones. Following the simple rules will help you to avoid unpleasant situations related to equipment failure, unnecessary energy costs and additional expenses for repairs and maintenance. Purchase of ready chiller without professional calculations Nowadays you may find a wide range of ready-made chillers at the market. At first glance, such offers seem to be more attractive than searching for equipment that fits your individual needs. Conveyor chiller is unlikely to provide uninterrupted maintenance of comfortable room temperature. When selecting a chiller for efficient cooling, some nuances should be taken into account as follows: features of production and technical processes within the facilities, boiling temperature, temperature on evaporator, coolant consumption, condensation temperature and some other parameters. It is very unlikely that a random chiller fits such features. Professional companies that work  with refrigeration equipment may be a perfect choice when selecting features of a chiller for your specific needs. ARTS specialists have 20 years of experience in this field and therefore perform precise calculations and selection of equipment based on specific parameters of buildings and your specific needs. Purchase of used equipment Some owners of buildings decide to buy a used chiller in order to save money instead of purchasing the brand new. Common problems they may face during operation of cooling equipment are leaking oil, noise in compressor, failure of fans or heat exchangers. Repair of such equipment is expensive. BY comparison, new high-quality equipment that is selected by specialists operates smoothly and does not caus such problems. The higher the pumping pressure, the better “The higher pressure

Experts of World Health Organization (WHO) have been conducting research for many years and finally have made depressing conclusions.  They state that faulty ventilation system within buildings increases the risk of transmission of viral diseases by 75%. Because majority of people spend up to 90% of their time indoors, the air in offices and homes may directly affect their wellbeing. Considering COVID-19 pandemic and its high spread, it is extremely dangerous to stay in rooms with faulty ventilation. Climate control company, ARTS, will help you to restore microclimate and make the air in your buildings safe. Causes of “sick” buildings    Scientists first accepted that the air inside buildings directly affects human health and wellbeing in the late 1970s. It was preceded by the fact that in 1973 there was oil embargo and measures were taken to reduce amount of air for ventilation of premises. After that, more people immediately started to complain about their poor health while being in certain premises. In the report of 1984 and related studies, experts of WHO noted that about 30% of new and restored buildings around the world may have a direct connection with poor health due to low quality of indoor air. Two years later, official term “Sick Building Syndrome” was introduced. Experts identify several types of pollutants that cause deterioration of indoor microclimate and cause emergence of “Sick Building Syndrome” over a period time. These include the following chemical pollutants: dust coming from the street, car exhaust fumes, production emissions. Sources of contamination may also be located in the premises themselves. They may be produced by building materials used for decoration of premises, carpeting, upholstery of furniture, combustion products of gas stoves, emissions of electrical devices, household chemicals. Air quality also worsens due to biological pollutants: pollen of plants, particles of wool and skin of pets, bacterial cells, aerosol particles of viruses, fungal spores, mold, dust mites. Ventilation can be a significant pollutant of indoor air. Ventilation process is actually designed for replacing of used indoor air with the fresh one that is supplied from outside. Good care is often not taken of ventilation system. This way air exchange is disturbed by breakdowns or blockages of ventilation ducts. Up to 40% of pollutants and bacteria can enter premises through faulty ventilation. Dirty ventilation increases the risk of transmission of viral diseases by 75% and under conditions of the pandemic, COVID-19 may spread among office workers and industrial premises. Properly working ventilation system may help to solve a number of problems. In most cases it may completely “heal» the building and create favorable microclimate in the premises. How “sickness” of buildings is dangerous for people  A lot of dust and high concentration of pollutants accumulate in the rooms with bad microclimate and low quality ventilation.  It also results in the spread of harmful microorganisms, bacteria, mold and fungus. Long term stay in rooms with “Sick Building Syndrome” may worsen the state of health that manifests in various symptoms. People that stay in rooms with unhealthy microclimate may experience/have psychoemotional discomfort, rapid fatigue, decreased concentration, headaches, dizziness, throat and nose irritation, runny nose, sneezing, difficulty breathing. The condition may even get worse if a person suffers from any allergies, respiratory diseases or asthma. It is easy to identify whether you have “Sick Building Syndrome” or not.  It is enough to track when and where symptoms express. As a rule, symptoms express and worsen while being in unhealthy room for a long time. On the contrary, they would weaken and disappear when you have access to fresh air or change your location. Types of contamination Contamination within the ventilation system may form for a number of reasons. Method of cleaning highly depends on the nature of its origin. Common types of contamination are the following: — Dust and dirt coming from the street and premises that sets down on air duct or filter; — Mold and fungus reproduce when rapid temperature changes occur due to circulation of humid air in the duct or moisture condensation; — Rust may form on the walls of the duct due to high humidity of the circulating air. Later it may result in formation of cracks in the air duct and/or failure of equipment; — Fat accumulation is the common case for homes and restaurants. It results in blockage of air ducts, check valves and decreases efficiency of ventilation; — Accumulation of chemicals and reagents in ventilation system of laboratories, research rooms, chemistry classrooms at schools; — Increased number of dangerous bacteria and viruses caused by rare cleaning and disinfection of the system in medical institutions; — Contamination after flooding or fire is a rare one that occurs suddenly and irregularly but requires urgent cleaning. When ventilation system needs cleaning  Norms of air exchange required for maintaining healthy indoor climate are outlined in construction and sanitary rules. Diagnostics and cleaning of operation of ventilation system shall be at least once a year in accordance with the norms. The same frequency of cleaning and disinfection of ventilation is specified in the Order No. 758 of the Minister of National Economy of the Republic of Kazakhstan as of December 9, 2015. Established norms and rules, at the same time, also cover conditions for servicing of ventilation equipment with consideration of operating instructions for each individual device. Frequency of cleaning of ventilation system depends on location and intensity of its operation. For instance, supply and exhaust ventilation systems of industrial and technological workshops, educational institutions and medical organizations shall be in strict compliance with maintenance regulations that define their cleaning every six months, every four months. If any intensive works and high operating loads, they need to be cleaned once a month. Why it is important to entrust cleaning of ventilation to professionals only Only professional companies can properly identify operational quality of ventilation system and degree of its contamination. They have special diagnostic devices and professional equipment for cleaning and disinfection. Owners of buildings often try to clean ventilation system on