Home » BEMS and controls service and maintenance

BEMS and controls service and maintenance

Building Energy Management Systems (BEMS) and controls systems maintenance comprises of service checks – to confirm correct operation – and energy optimisation of all system parts.

The BEMS and controls systems monitor and control a building’s services, such as, heating, ventilation and air conditioning (HVAC), water, electrical and lighting services.

While BEMS and controls systems perform some of the same basic control functions, they differ in their overall capabilities.

Building energy management system (BEMS)

A BEMS differs from a controls system insofar as, it has superior technical ability and graphical interfaces. It also has the ability to remotely access and connect to systems. Therefore, they are mainly accessed and controlled from a computer. Additionally, some BEMS are fitted with a touch screen display for ease of control for the end-user.

The acronym BMS is also used, sometimes interchangeably with BEMS. Essentially, they perform the same functions, however, a fundamental feature of a BEMS is energy reporting and connectivity.

Controls system

Controls systems are more minimal and discreet. They offer simpler controls on a more basic user interface – often a wall-mounted keypad.

BEMS and controls maintenance preparation

In carrying out service and maintenance activities, the first step is for the service engineer to furnish building facility manager or other relevant parties with work method statements. Then a site risk assessment must be conducted. Together these are known as RAMS – risk assessments and method statements. They document site-specific hazards, working risks and their associated control measures. In the case of BEMS and controls systems, the main hazard is electricity, where the risk of electrocution is present.

Secondly, service engineers must apply asset labels and asset tag all BEMS and controls plant items. This provides traceability, tying all service, maintenance and repair work back to each individual asset item, via a unique number.

Ideally, all activity history should be recorded in a computerised maintenance management system (CMMS) for ease of record retrieval. If not, a logbook should be created, with records retained to comply with industry standards.

A CMMS also provides transparency in ensuring only engineers’ working hours associated with particular jobs are charged, by automatically connecting working time with specific customer accounts.

BEMS and controls service and maintenance checks

Service and maintenance of BEMS and controls systems include: a thermal scan of system panels, checking wiring in the motor control centre (MCC), checking correct calibration of temperature sensors – inside and out – actuator checks, relay pack checks and controller communication proof.

BEMS and controls service and maintenance checks should also take place on the system computer and or keypad interface. This is because the software contained within both are responsible for controlling the entire systems. This will prove or otherwise that operation is in-line with specifications and commands set up on the computer’s software strategy.

A back-up copy of the BEMS and controls software strategy should be kept in a separate secure location, in case of damage or corruption of the strategy. This would avoid the substantial cost associated with re-writing the strategy, which is a time-consuming task. To reduce the risk of corruption, the BEMS should be controlled from a segregated, stand-alone computer.

For optimal efficiency these service and maintenance checks should take place twice per annum.

The BEMS service engineer

The BEMS service engineer must be appropriately trained and attired to in personal protective equipment (PPE) to carryout maintenance.

Ideally, a BEMS service engineer should possess an electrical qualification, so they can also carry out any minor electrical repair or upgrade works – reducing costs and setup times. An electronic engineering qualification, or similar would also be desirable, to verify and oversee that controls and their interdependencies with connected systems are operating in a safe and efficient manner.

Benefits to BEMS and controls maintenance

The benefits to performing service and maintenance are threefold.

1. Monitoring and control – energy saving

Monitoring and control provide a real time view of energy consumed by HVAC, water, electrical and lighting services. That then allows for an appraisal of current energy use. From there, energy saving targets can be setup and an energy management plan implemented. This information can then be presented on a user-friendly computer dashboard display.

Also, BEMS features such as weather compensated controls can also save energy – using set points and parameters around the building – conditioning the inside building temperature, appropriate to outside weather conditions.

2. Critical alarms

As an additional measure, alarms can also be set up, to alert if specified services operate outside of set parameters. This is particularly useful for any operation linked to a business-critical process, i.e. where a product is made or stored in a temperature-controlled environment, like a medical device.

3. Graphics

Adding graphics to a BEMS can also be useful way to quickly diagnose any anomalies, by gaining a holistic view of the entire services on a computer screen. This saves time, particularly if the BEMS can be remotely accessed and monitored.

Implications of no BEMS and controls maintenance

1. Energy waste

With 45 to 65% of energy use in a building (typically) related to heating and hot water, BEMS and controls maintenance would prove a worthwhile investment, providing precise control and cost savings of these services.

Without maintenance inefficient plant and equipment can often go undiscovered. This can be due to incorrect calibration of controls, i.e. plant unnecessarily operating outside of building occupancy hours, wasting huge volumes of money on energy.

2. Uncomfortable conditions – increased complaints

Insufficient control could lead to increased complaints from staff, customers and visitors alike. This in turn can evolve into industrial relations issues and reputational damage amongst stakeholders or both. Unmaintained HVAC, water, electrical and lighting services may not operate within desired design parameters to the comfort satisfaction of building occupants.

This may also lead to downtime if the BEMS and controls systems are linked to operations that are part of a business-critical process.

3. Health and safety

If you are reliant on BEMS and controls systems to manage the functions of building services plant, the absence of maintenance could lead to health and safety issues. Lack of attention to safety could cause injury or death, particularly in dealing with water systems, where pipework is vulnerable to Legionnaire’s disease. This is crucial, particularly in a more technically advanced BEMS, i.e. where hot water creation is reliant on several controls.


Additionally, due to increased scrutiny of use and the rising cost of energy, European and Irish legislation require control systems in most buildings before 31 December 2025. Prudent planning to install or upgrade building controls should budget to comply with the following requirements.

A new building shall, where technically and economically feasible, be equipped with self-regulating devices for the separate regulation of the temperature in each room or, where justified, in a designated heated zone of the building unit…

energy performance of buildings

If heating or combined space heating and ventilation output exceeds 290 kW, or if air conditioning or a combined air conditioning/ventilation system output also exceed 290 kW:

An existing building (other than a dwelling) shall… where technically and economically feasible, be equipped with a building automation and control system.

energy performance of buildings

Remote access and monitoring

Installing remote access and monitoring can give service engineers a view of a site-based BEMS from any position with an internet connection. This will allow for PPM savings through fewer physical callouts.

Service engineers can access the BEMS through a remote access router over a secure internet connection. As a result, remote access and monitoring will realise monetary and environmental savings.

Cylon BEMS

One such BEMS provider is Cylon. Cylon is a recognised international leader in the development of smart energy management systems. Thermodial are Cylon Active Energy Technical Partners allowing our service engineers access to Cylon systems, hardware, software and support. Cylon Active Energy provides a cloud-based, real time energy management service – view video on how savings can be achieved.

Thermodial’s approach

Thermodial maintenance of BEMS and controls systems are carried out by multi-skilled service engineers with extensive knowledge of how building services function. These service engineers have the greatest understanding of how the systems practically operate and integrate from their experience at performing planned preventative maintenance (PPM) of HVAC, water, electrical and lighting services.

Thermodial BEMS and controls service visits also take place alongside HVAC, water, electrical and lighting services PPM, to ensure the harmonious operation of all systems. This ensures energy saving plans are implemented and are practically achievable.

ISO 50001 – energy management system

Thermodial are certified to ISO 50001 – 2018 standard. From our experience at achieving this high standard, we can walk you through and assist you in the energy management process.

Talk to Thermodial about BEMS and controls maintenance, a Cylon Active Energy system or your energy management system – to support your businesses’ specific requirements.

Key guidance source materials

European Union (Energy Efficiency) Regulations 2021 | S.I. No. 393 of 2021

Customer testimonials

After Thermodial helped investigate and repair our heating and control issues, comfort conditions increased and we realised two-fold savings on energy costs. The boiler no longer needed to operate 24/7 and local electric radiators could be removed.

Niall O'Riordan

Before Thermodial installed the energy controls and condensing boilers, I dreaded entering the building in the mornings, in case the boilers had tripped overnight and there was no heating. The energy controls installed by Thermodial helped us on three levels:

  1. lowered our energy consumption;
  2. we could precisely control and alter temperatures in different areas;
  3. the calendar function allowed us to set adequate controls for holiday periods.
Elizabeth Carpenter (Principal) Taney Parish Primary School
Elizabeth Carpenter (Principal)

Latest News

Energy management – Thermodial certified to ISO 50001

Energy management and consumption are among the topical items on the world's current climate change agenda. Thermodial were recently awarded ISO 50001 certification for energy management and we believe we have achieved a sector first in attaining this updated energy...

read more

From the news archives…

excellence over time – our 30th anniversary

It is our 30th year in business and we were celebrating by adding some new livery to our vehicle fleet this week. Keep an eye out for our 30th anniversary logo. Our message is a simple one – excellence over time. Excellence over time speaks of the experience and...

Talk To Thermodial

When Thermodial were founded in 1986, the founders had a vision of an engineering focused service, but also one that was responsive and reliable.

This belief should hold true to dealing with questions or information requests, such as one you may have.

Please contact us by filling in the form below, for a prompt response; email info@thermodial.ie or ring us in Dublin.

As the experts in HVAC maintenanceupgrades and energy management, we would be happy to respond to your requests.