What makes a good PICV?

by Andrew Pender, National Sales Manager at FloControl Ltd.

Over the last 5 years, PICVs have been widely accepted as the best method of terminal control in variable flow systems due to their energy saving potential.  The surge in popularity has led to an influx of products with varying designs, features and functionality.  This article reviews some of the mechanical PICV design elements and how they can impact on the PICV’s performance in an applicational context.

Where do we start?

To help specifiers and project engineers assess which PICV is best suited for an application, the BSRIA BTS1/2019 standard has been developed to provide a consistent test method for PICV manufacturer’s products to be benchmarked against.

Manufacturers should be able to provide test results in line with this technical standard which covers:

  • measured flow vs nominal flow
  • pressure independency or flow limitation
  • control characteristics, both linear and equal percentage
  • seat leakage test

Repeatability & Accuracy are central to the tests and they are key to good temperature control and realising the full energy saving potential of a PICV installation.

An accurate PICV means the measured results will be equal or very close to the manufacturer’s published nominal flow rate each time it is measured, known as low hysteresis.

Accuracy has a positive impact on a building’s energy consumption.  “Measured over time, a 1% increase in the accuracy of a PICV can result in a reduction of around 0.5% in the building’s overall hydronic energy consumption” (FlowCon International).

Valve accuracy is driven by the design, manufacturing process and material used for the internals of the valve.

  • The design of the PICV should allow for Full Stroke Modulating Control at all flow settings without any stroke limitation.  The flow setting and temperature control components should operate independently.  Some PICV designs use the stroke of the actuator stem to set the flow rate resulting in limited stroke and control.  This can cause issues at low flow rates whereby the PICV effectively becomes on/off irrespective of actuator selection.  
  • The manufacturing process and the component materials also contribute to accuracy. For example, injection-moulded, glass-reinforced composite materials cope better with water conditions that valves can be exposed to.  They also have less material shrinkage than other materials, delivering higher accuracy than valves that use alloy components.

What else should be considered?

The importance of accuracy and repeatability are paramount when selecting a PICV however there are other factors that should be considered:

  • Wide flow rate range – including low flow rates for heating applications, ideally covered by a small number of valves.
  • Setting the flow rate – setting the PICV can influence the accuracy. There are various scales used including set points related to flow rates and percentages. PICVs with very detailed scales with small increments between set points are more difficult to set accurately, leading to higher tolerances than the BSRIA standard recommended + 10%.
  • Wide ΔP Range – low start up pressure. To operate satisfactorily, the PICV requires a minimum pressure differential to overcome the initial spring resistance within the PICV, enabling the spring to move and take control. Care should be taken to ensure the minimum pressure differential is as low as possible to maximise the energy saving potential of the system.  The maximum DP should also be considered to ensure the PICV operates effectively under part load conditions.
  • Dirt tolerance – the Valve Control Opening Area [A] on all PICVs, irrespective of the manufacturer, is identical for each flow rate. The shape of the Control Area can be different depending on the valve design. A Rectangular flow aperture is more tolerant than an Annular flow aperture. Debris will pass through the rectangular aperture more easily.
  • Removable inserts – deliver the greatest flexibility and serviceability.  Products can be easily serviced in line without disruption. This is especially of value when water quality is poor or when flow requirements change due to changes in space usage.  Inserts can also be removed during flushing.  Valve bodies can be installed with blank caps eliminating the risk of damaging or contaminating the PICV element, whilst having a full-bore flushing capacity.
  • Installation – PICVs in general have no installation restrictions however in line with BSRIA BG29/20, it is recommended that PICVs should be installed in the return branch as small bore PICVs will have a high resistance which will hinder the flushing velocity during the forward flushing of terminal units.

Making the right choice

There are many aspects for specifiers and project engineers to consider when selecting the right PICV for an application.  The BTS1/2019 standard provides an excellent benchmark, but the individual designs also need to be carefully considered.  A correctly selected PICV will ultimately lead to a more comfortable indoor climate with better control of the space heating and cooling as well as potentially reducing the pump energy consumption in a building by up to 35%.

This post was authored by Andrew Pender, National Sales Manager at FloControl Ltd. All views expressed are those of the author. If you belong to a BSRIA Member company and wish to contribute to the BSRIA Blog, please contact marketing@bsria.co.uk

Shift in Construction Technology for a ‘post-Covid, pre-vaccine’ era

by Amy Butler, JB Associates

In 2017, McKinsey Global Institute slated construction for evolving at a ‘glacial pace’ due to its ranking as the least-digitised industry in Europe. While plenty of technological advances were pitted as ‘on the horizon’, many companies were reluctant to take the necessary steps to push forward with digitisation. Critics warned that a lack of innovation would lead to companies folding, although it took a global pandemic before this prophecy materialised and those without suitable digital infrastructure in place were shaken.

The pandemic is now considered a catalyst for industry improvement, propelling construction out of its ‘glacial’ evolution and deep into the digitised era. A recent study undertaken by Procore found that two thirds of the surveyed construction companies had rolled out new technology during the lockdown, with 94% of these seeing an improvement to productivity and teamwork. However, what exactly are these technologies and where do we go from here?

Smart Buildings

While we are all now experts in the world of Zoom and Microsoft Teams, the challenge lies in returning safely to offices and various other workspaces. With many UK companies pushing for their teams to be back in work physically, how do we ensure that commercial buildings remain safe? Smart Building technology is reshaping the workplace and ensuring safety as well as energy optimisation. Buildings with integrated BMS systems and IoT sensors were already an option before the pandemic. Now, they are a wise choice for business owners.

Essential for a post-Pandemic and pre-Vaccine era, IoT systems can control air quality and ventilation. High-performance air filters and moisture controls will now be key due to Covid-19’s airborne nature. OKTO Technologies (Smart Buildings specialists) have even launched an Artificial Intelligence-led air filtration solution that is reportedly so advanced it can eliminate 99.98% of SARS-CoV-2 (the virus that causes Covid-19) from the air in 10 minutes.

Similarly, density control counters and heat detection cameras can be incorporated into BMS systems to ensure that viruses are less likely to spread or enter into a facility. Airports have been trialling infrared cameras to measure body temperatures for a fever and several companies offer leases or installations for these cameras. While they are not a definitive medical diagnosis, they add a level of reassurance. This may be the aim of much of this technology; a form of due diligence in protecting staff.

BIM & VR

Technological advances are also prominent on site. Construction News reported that contractors employed for the Nightingale Hospital projects found huge value in Autodesk programs. A vital tool for tracking constant streams of updates in rapid working conditions, construction management software proved its worth in recognisably challenging projects across the UK.

As social distancing measures remain in place, it is imperative that technology is prioritised; virtual communication is still far safer than face-to-face. Software like BIM is also providing insights and tools to manage projects during a more challenging time. Even more impressively, companies are merging BIM models with the cloud, GPS and Virtual Reality software. This development means a ‘digital twin’ of a facility can be created and it opens a world of opportunities for Project Management and Design efficiency.

Remote working could even be a trend that stays long past pandemic precautions. Drones have been used previously to reduce safety hazards for technicians and now may be utilised in future remote inspections. Similarly, researchers at the University of Strathclyde have been given £35,000 in funding to create a remote inspection system. The 3D immersive building environment program aims to reduce risks by eradicating the need for Quantity Surveyors or Health and Safety Inspectors to be physically present on site.

Whether enabling remote working, improving the health and safety of commercial buildings or aiding on-site processes, technology has become a necessary tool for construction in the last 6 months. The companies that had embraced digitisation long before 2020 were undoubtedly the ones able to continue thriving in the tough lockdown period. The next step is for many companies is to streamline their management processes or workplace systems to ensure technology works for them as efficiently as possible. Breaking out of its inertia, construction’s ‘glacial evolution’ is firmly in the past and technological advances are here to stay.

This post was authored by Amy Butler of JB Associates – building consultancy specialists. The views expressed are those of the author.

BSRIA Members wishing to make a guest contribution to the BSRIA Blog should please contact marketing@bsria.co.uk

How hard can opening a new office be?

As some of you may or may not be aware, the new BSRIA North site is now open for business.

For organisations opening a new office or site, it should be a time of great anticipation and excitement as the company sets out a new path, but for many they approach this process with fear and trepidation and for those tasked with the job of making it happen, it can potentially be an extremely stressful period of time.  As Project Manager for the setting up of BSRIA North, I thought I would share with you my experiences – the very good, the sometimes bad and the occasional ugly!

This blog was written by June Davis, Business manager of BSRIA North

I will be sharing my experiences and tips on:

  • Identifying and interpreting the business requirements
  • How to determine the must have’s versus the nice to haves
  • The importance of establishing an internal project team – you can’t do this alone!

BUSINESS NEEDS

When establishing the business needs, spend time with colleagues from across the organisation to listen and understand what they would like to see from a new base – what is it about the current environment that works, what doesn’t work so well and what would improve their working environment if only it were possible!

Everyone one I spoke to was really keen to give me their wish lists and as I started to jot their ideas down, some similarities started to emerge, but for some their thoughts varied significantly.    Prioritise the must haves and rationalise the nice to haves and a vision of your new building will start to emerge.

TIP don’t lose those more obscure requests. Whilst on this occasion I couldn’t deliver a building that had an on-site wind turbine, I was able to deliver on the overhead gantry crane!

TIP:  to fulfil everyone’s requirements you would most likely need to commission a bespoke building, so make sure to manage expectations!

Internal Project Team

You can’t succeed on your own so it is imperative that you establish an internal project team.  Working with business managers from across the organisation proved a valuable source of knowledge and support.  Individual managers were allocated areas of responsibility spanning right across the project and each were tasked with identifying what needed to be done , this formed the basis of a project plan.

Example project areas:

·         Property

·         Fit out

·         Process/Systems

·         Health & Safety

·         Quality

·         Marketing

·         People

 

Ensuring the team communicated regularly weekly meetings were held and if on occasion some colleagues were unable to attend it ensured that we kept abreast of developments – or on occasion the lack of!

Select a property

It seems obvious, but finding the right property in the right location and that meets the detailed specification your colleagues have challenged you with can at times feel like finding a needle in a haystack. This is where the word compromise well and truly comes in to play!  Give yourself a sizeable geography in which to search for property – like you, everyone wants it all, so make sure you keep an open mind and research those properties that at first glance you would dismiss as not meeting your criteria.   What you think you need and what you finally agree is ‘the one’ may well prove to be completely different – it did for us!

TIP The more sites I visited the more ideas I collected as to what could work and might be achieved!

 TIP:  Draw up a short list of buildings and compare them to your must have list – is there a property that is starting to lead the way?

TIP:  Engage one of your project team to come with you to revisit your top properties – they will bring a new perspective to things.

TIPIf possible, establish a good relationship with the previous tenant, in our experience they were really helpful in providing information about the building, how it operated and its history!

The legal process can take quite some time, it was certainly longer than we had anticipated; but don’t underestimate this vital element of the journey. It is critically important that your future building has the correct legal foundations in place, so ensure you seek good advice.

With the legal aspects complete we gained possession of the building and we all got a much-needed motivation boost! The project team visited the site to design the layout and agree what renovations needed to be made.  The vision was taking shape!

Renovations and installations!

Be ready – This is an extremely busy period.  Obtaining quotes, liaising with contractors, arranging building services are just a handful of the tasks at hand. I found that having someone local to the site with good local knowledge is hugely helpful.  Access can be required at various times of the day and sometimes night but with the building not yet fully functional requires a lot of coming and goings to site.   Ensure the alarm systems are serviced and activated and site security implemented.

TIPTake your readings!  Ensure you capture the utility readings on day one and contact the associated providers to inform them you are the new tenants submitting the readings.  This should be a straightforward exercise I can assure you it isn’t, so be warned!

 

For those who may be undertaking a similar process either now or in the future, I wish you every success.  My recommendation is to ensure you appoint the right person to lead the project, a person who loves to do detail, enjoys multi-taking, doesn’t mind getting their hands (very) dirty, and has the patience of a saint and most importantly a good sense of humour!

BSRIA North is proud of what has been achieved and we forward to welcoming you through our doors – please visit us any time!

TRANSFORMATION OF THE OFFICE

 

 

 

 

 

 

 

Being a Young Engineer

This blog was written by Laura Nolan, Sustainability Engineer at Cudd Bentley Consulting

This blog was written by Laura Nolan, Sustainability Engineer at Cudd Bentley Consulting

What is it like to be a young Engineer?

I think it’s fair to say the term Engineer in itself is very broad so for the purpose of this blog my focus is my discipline, Building Services Engineering.

So how did I become an Engineer? Through my love of maths and problem solving, I chose to study a common entry Engineering Degree in Dublin Institute of Technology. Following the first year of Maths, Applied Maths, Physics and Chemistry, I then chose the Building Services route as it seemed the most interesting to me and it was. It offered modules in a wide range of subjects from lighting design, fire engineering to smoke control and acoustics. As well as the heating, cooling and ventilation design as you would expect.

I graduated in 2010 from Dublin Institute of Technology to a bleak construction industry in Ireland so I looked elsewhere and succeeded in getting a job here at Cudd Bentley in Ascot. Since graduating and entering the workplace as a Consultant Engineer, no two days have been the same, each week offers new challenges and the range of projects I have been involved in has been exciting. Projects I have been involved in range from retail to residential, shopping centres to extensive refurbishment projects. I work as part of a team and although I am mainly office based, I regularly visit site to carry out inspections or for Design Team meetings, offering an enjoyable diversity to my job.

Quite quickly into my career I realised my interest in the area of Sustainable Engineering Design and with the support of my company, Cudd Bentley Consulting, I have completed a range of courses including CIBSE Low Carbon Energy Assessor, Elmhurst On Construction Domestic Assessor and Bentley Hevacomp modelling course to allow me to be proficient in thermal modelling and a Low Carbon Consultant. I really enjoy building modelling and have had the opportunity to work with some interesting models here at Cudd Bentley. I use my models to generate a variety of outputs including heat loss and heat gain calculations, energy and carbon saving potential, overheating analysis, Energy Performance Certification and Part L Compliance.

Sustainability is an area that I am particularly interested in and this year I have begun an MSc in Renewable Energy in Reading University. I enjoy learning and I don’t think I will ever be finished learning. Topics which I am particularly interested in currently are Nuclear Energy and the Feed in Tariffs Scheme for solar energy. I think it will be a real shame if the Government chose to drastically reduce the Feed in Tariff Scheme. I am also eager to see what will come from the Climate Change Conference, COP21, in Paris this month.

I have been attending events for the BSRIA Young Engineers Network for the past five years and I was delighted to be asked to be the Chairwoman of the Network this year. I would encourage all young Engineers to attend as it gives a unique opportunity to meet experts in their field, discuss current topics with your peers and to network with fellow young Engineers.

I was fortunate to be surrounded by highly experienced Engineers from the beginning of my career and one piece of advice I would offer every young Engineer is to immerse yourself in the knowledge of those people around you with such experience as well as making sure to put your own young and fresh approach to it where appropriate. The industry is constantly changing and it’s important to be constantly evolving.

Being a young Engineer is challenging, exciting and for me a fantastic career.

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