Integral and Sustainable Air-conditioning in The Hospital Sector

For a correct integral and sustainable air conditioning of hospitals, we must pay special attention to the physiological and hygienic requirements of these, that is, we must be clear about how the environment has to be inside hospitals in general, and specifically in the different rooms that we find inside these buildings…


Active-Passive Heat Recovery Ventilation

When ventilating spaces with human presence, it is essential to take into account the ventilation standards or needs that each room requires, depending on its characteristics…


Refrigerant Gases

What are refrigerant gases? This is the question that many people who work with them in their daily life may ask themselves. 


Indoor Air Quality in Hotels (IAQ)

When we talk about air conditioning in hotels, we always think about rooms and these environments comfort. But Hotels functionality is not only that, Restaurants, Bars and Entrance Halls are places that can be complex when it comes to air conditioning…


Ventilation and Volatile Organic Compounds VOCs

Hospital environments, not only operating theatres, infectious wards, burns or ICUs, are complex and require special measures to achieve healthy indoor air quality (IAQ), making them safe workplaces and optimal environments for patients and their companions. To achieve these air qualities, the use of Air Handling Units (AHUs), selected and customised to the needs of the different rooms, is required.


Heat Pump Principle

As a starting point to understand how a heat pump works, it is necessary to know the fundamental physical principle of Heat Transmission…


Photovoltaic Heat Pump Hybridisation

When we talk about renewable energies, there is no doubt that the first concepts to come to mind are solar thermal and photovoltaic energy, others such as wind, geothermal or tidal energy, although we also know them, are secondary. But traditionally these two have been renewability queens…


Metabolism and Ventilation in Heated Pools

The treatment that has been made to date of the Regulations and Regulations has not been very rigorous. Solutions have been taken which, although accepted by the majority, sometimes do not comply with the required requirements. This is one of those cases, and this time, in addition, related to the ventilation of the air-conditioned premises…


Hospital Air Conditioning

The Regulations of Air Conditioning and Ventilation of Hospitals are wide, the diversity of Zones to be air-conditioned and ventilated so indicate. From corridors to operating rooms, from delivery rooms to examination rooms, … the typologies and needs are very varied and different. Until today, where one characteristic is common to all, the defense against SARS-CoV-2 …


Photovoltaic Heat Pump

The global targets for decarbonisation and the reduction of greenhouse gas emissions raise the increasing use of renewable energies. Within these, photovoltaic solar energy is an energy source that produces electricity of renewable origin, obtained directly from solar radiation by a semiconductor device called a photovoltaic cell…


Industrial Air Conditioning

The air conditioning concept includes thermal, hygrometric control and ventilation levels to reduce the concentration of pollutants, VOCs, … As is easily understood, in the industry the concepts of thermal and hygrometric comfort can be complex to achieve. Industrial buildings are not offices where these parameters are …


Monitoring and Control Systems in Hospitals

From KEYTER, in collaboration with HEATCOOL, we face this problem for different Hospitals. For this joint project, KEYTER has developed a control system specially designed with the aim of protecting health personnel and other users of hospital centers, in the case of highly infectious diseases, and patients with immune system problems who are hospitalized.


Centralised 2-pipe systems for heating and DHW

generation using Aerothermal energy

Keyter organised in collaboration with Uponor, leader in underfloor heating, geothermal, multilayer piping, Invisible air conditioning, plumbing and PEX an exclusive Webinar.

The reversible heat pump

How to keep the refrigerant content small and guarantee a constant (high) water temperature at low outdoor temperatures.

UV-C systems against COVID19 (SARS-CoV-2)

Ultraviolet C (UV-C) light has been identified as one of the most important barriers to preventing SARS-CoV-2 (COVID19) airborne infections.

Screw chillers with refrigerant 1234ZE

In 2004 fluorinated gases emitted by the refrigeration/air conditioning industry were responsible for 1.3% of global warming, up to 7.9% by the year 2050.

Different ways for dehumidification

The motivation and need to tackle the project is due to the fact that most of the facilities in the non-residential building sector have a high latent load.

Airconditioning for large spaces

In the recent years, there has been an increase in the regulatory requirements regarding indoor air quality and energy savings in large commercial area projects.

Climate efficiency in hotels

Due to the European policy, hotels must improve their energy efficiency and reduce their gas emissions.


Technical Guide 01: Maintenance of thermal installations

The technical instruction IT3 of the RITE establishes the obligation to design specific maintenance programs for the thermal installations of buildings, which must contain the programming of the necessary tasks, as well as the documentation and filing procedures of all the preventive and repair actions that take place in each specific installation. The maintenance programs, as well as the records foreseen in them, will allow third parties to verify that the expected performance of each installation is being maintained.

Technical Guide 02: Procedures for the determination of the energy efficiency of water chiller plants and autonomous air handling equipment.

This document summarizes, with eminently practical and application criteria, a guide to the procedure to be followed for the determination in situ of the instantaneous operating performances of the refrigeration equipment most frequently found in the air-conditioning installations of our buildings, specifically water chiller plants and air cooling equipment by mechanical compression cycle, both reversible and non-reversible, explicitly taking into account the difficulties involved in measuring the operating parameters of refrigeration equipment, far from the working conditions provided by a test bench, and once integrated in the context of a real and concrete installation, which directly affects them.

Technical Guide 03: Design and Calculation of Thermal Insulation of Piping, Appliances and Equipment

This document provides the calculation methods and standard sizing criteria for the estimation of the insulation thickness to be used in equipment and elements of the building and industrial installations. These calculations are carried out in steady state and one-dimensional flow.

Technical Guide 04: Cooling Towers

This technical guide is based on the current Spanish situation of cooling towers in thermal installations in buildings, in the sense that they are considered as a risk factor for the spread of legionella. For this reason, there is a significant decrease in the installation of this equipment in the building sector, which leads to a decrease in energy efficiency and, as a consequence, higher energy consumption.

Technical Guide 05: Consumption Accounting

The purpose of this document is to establish the requirements to be met by the consumption measurement instruments (water, energy supplied to the thermal power plant and useful thermal energy supplied to the building), which must house the thermal installations in buildings, as well as the accounting of such consumption, in order to achieve continuous monitoring of the energy efficiency of the installations and their hot water consumption.

Technical Guide 06: Central Sanitary Hot Water

The purpose of this guide is to analyze the installations of centralized production of domestic hot water (DHW), from the points of view of energy efficiency and regulatory compliance.

Technical Guide 07: Outdoor Climatic Conditions of the Project

The aim of this technical guide is to provide updated information on the outdoor climatic conditions commonly used in the design of heating, cooling and domestic hot water installations in buildings to meet the demand for human comfort and hygiene.

Technical Guide 08: Energy Saving and Recovery in Air Conditioning Installations

Throughout the guide, emphasis is placed on the need to carry out energy simulations of the different combinations, both to estimate the real needs of the buildings (demand) and the real performance of the equipment (partial load, performance depending on outdoor conditions, etc.)

Technical Guide 09: Closed Loop Geothermal Exchange System Design

Geothermal energy is among the least exploited renewable energy sources in our country, a situation that has generally been justified by the low development potential that this form of energy use supposedly presents. This assessment is actually a mistake, as it confuses the part with the whole; in this case, high temperature geothermal energy (associated with large geothermal gradients and electricity production) with geothermal energy as a whole.

Technical Guide 10: Air Conditioning Installations with Autonomous Equipment

This document describes the application of :
– Welfare and hygiene requirements (IT 1.1)
– energy efficiency requirements (IT 1.2)
– safety requirements (IT 1.3)
– Examples of system application

Technical Guide 11: Water Air Conditioning Installations

This document describes the application of :
– Welfare and hygiene requirements (IT 1.1)
– energy efficiency requirements (IT 1.2)
– safety requirements (IT 1.3)
– Examples of system application

Technical Guide 12: Selection of Fluid Conveying Equipment. Pumps and Fans

Pumps are mechanical devices used to transport liquids through piping networks. This paper focuses on pumps used in closed circuits of heating, air conditioning, solar energy and domestic hot water installations.
Fans are mechanical devices used to transport air in ventilation and air conditioning ducts. In this paper we will focus on fans used for supply and exhaust air in ventilation systems and for supply and return air in air conditioning systems.

Technical Guide 13: Comments Rite-2007. Regulation of Thermal Installations in Buildings

The Regulation on Thermal Installations in Buildings, RITE, establishes the energy efficiency and safety requirements that must be met by thermal installations in buildings to meet the demand for the well-being and hygiene of people during the design, sizing and assembly phases, as well as during their use and maintenance.

Technical Guide 14: Average Seasonal Performance of Heat Pumps for Heat Production in Buildings

The Regulation on Thermal Installations in Buildings, RITE, establishes the energy efficiency and safety requirements that must be met by thermal installations in buildings to meet the demand for the well-being and hygiene of people during the design, sizing and assembly phases, as well as during their use and maintenance.

Technical Guide 15: CO2 Emission Factors and Coefficients of Pass-Through to Primary Energy of Different Final Energy Sources Consumed in the Building Sector in Spain. Recognized Document Effective as of January 14, 2016

The purpose of this document is to review and update the pass-through coefficients from final energy to primary energy, and to CO2 emissions, of the different energies used in the building sector. The current pass-through coefficients and emission factors have been extracted from the recognized document “Acceptance conditions for alternative procedures to LIDER and CALENER”, and are shown in Annex I. The new proposed factors are included in Chapter 8: Updated pass factors. The calculation methodology for electrical energy is shown in Annex IV and Annex V, together with a comparison between the current and future values proposed in this document.




01 – Heat Pump Principle

02 – Refrigerant Gases

RITE in 30 minutes

Two-pipe centralized heating and DHW systems using Aerothermics

Hospital Supervision and Control Systems

Renewable and residual energies for Heat Pumps in the Hotel Sector

Active-Passive Heat Recovery Ventilation


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