Master Plan for the optimization of air quality and technical efficiency in the BC building of Mútua Terrassa

The University Hospital of Mútua de Terrassa has entrusted WATTEGA with the development of a comprehensive Master Plan aimed at optimizing its HVAC and ventilation systems. This technical consulting project addresses the challenge of adapting the installations of a complex hospital environment to current health and efficiency standards, ensuring maximum air quality in critical spaces while reducing the energy impact of the hydraulic distribution system.

Context and challenge: The hospital, originally built in 1999, features an HVAC system based on induction units and fan coils that required an in-depth strategic review. The main challenge was to carry out a detailed technical diagnosis to align the BC building with current air quality regulations (RITE 2021 and UNE 100713), as well as to resolve the high electricity consumption of the pumping system, which accounted for 30% of the total installation.

Project scope The assignment was structured into three phases of technical analysis covering the entire building:

• Phase 1: Analysis of the ventilation system and optimization of the riser architecture on floors 6 to 16.
• Phase 2: Diagnosis of the current state of ventilation and assessment of equipment replacement on floors -3 to 5.
• Phase 3: Study for optimizing the hydraulic distribution of HVAC water.

The study analyzed highly complex areas such as operating blocks, ICU units, delivery rooms, hemodynamics units, and hospitalization areas.

Services delivered: As part of the technical consulting, a comprehensive audit of the existing Air Handling Units (AHUs) was carried out, evaluating critical parameters such as outdoor air renewal rates, required filtration levels (F7/F9 or HEPA filters in operating rooms), and relative humidity control. Additionally, an improvement proposal for the hydraulic distribution system was defined to optimize energy consumption.

Technical development of the project: The engineering process focused on transitioning from systems operating solely under overpressure to models incorporating air return and energy recovery. The diagnosis identified the need to improve outdoor air intake by relocating it away from contamination sources and to implement humidification systems in areas required by regulations.

In the hydraulic domain, the analysis proposed replacing three-way valves with proportional two-way valves and implementing variable flow control based on a constant temperature differential. This change allows pumping to be adjusted to real system demand, significantly reducing the energy consumption of heating and cooling pumps.