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You are here: Home1 / Water2 / Closed Systems Water Testing

Closed Systems Water Testing to BSRIA BG 50/2013

BSRIA closed systems water testing to BG 50/2013Water Treatment Services offer a range of specialist closed systems water testing and laboratory analysis solutions to support BSRIA BG 50/2013 standards.

Our water quality analysis solutions cover a comprehensive range of important microbiological, chemical and physical parameters associated with the operation and maintenance of closed heating, chilled and cooling systems.

What is a closed water system?

A closed water system operates as a sealed or closed loop through which water can circulate without exposure to the environment, minimising water loss and the potential for contamination. They are typically used in HVAC heating, chilled, cooling, and industrial processes to improve efficiency and reduce costs. The benefits of such closed systems include improved efficiencies, extended equipment lifespan, reduced water loss, and better water quality.

Why test water in a closed system?

It is important that the water used in engineered closed systems should be tested at regular intervals. Checking for bacterial growth and monitoring the internal water chemistry and physical condition of the water can help to ensure that the system is kept under control and operates as it should.

Regular water analysis helps building services engineers, facilities managers and plant operators to identify potentially damaging water conditions that could cause corrosion, the build-up of scale and unwanted bacterial growth before they become problematic.

The full criteria and guidelines for closed system water analysis is established in the BSRIA 50/2013 publication “Water Treatment for Closed Heating and Cooling Systems”. The main recommendations dealing with water testing in the BSRIA guidelines state that new heating or cooling systems should be tested between one and three months after commissioning. It also suggests a more frequent schedule of water testing may be suitable during the first six months.

BSRIA water testing to BG 50/2013

Our specialist laboratory based closed system water testing solutions for closed-loop heating and cooling systems includes:

  • Laboratory Water Testing

    Professional laboratory analysis of water from closed heating and cooling systems to meet BSRIA BG 50/2013.

    Test for an extensive range of microbiological, chemical and physical parameters.

  • Microbiological Analysis

    Micro analysis for key parameters including aerobic colony count/TVC, nitrite reducing bacteria, pseudomonas and sulphite reducing bacteria.

  • Chemical Analysis

    Chemical analysis for a comprehensive range of parameters.

  • Physical Parameters

    Analysis for a range of physical parameters.

  • Water Sampling.

    Expert in-field water sampling.

  • Water Treatment Solutions

    With specially trained engineers, water treatment service specialists and trained technicians we can offer professional, cost effective support on all closed systems.

Full national UK coverage

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained engineers, water treatment service specialists and technicians we can offer professional, cost effective water testing, in-field sampling and laboratory analysis services across the UK and Internationally.

Contact Water Treatment Services today to learn how our professional laboratory analysis solutions can help improve the performance of your closed heating and cooling systems. To speak with one of our experts call us on 0330 223 31 31 or simply use this button.

Contact Us Today

BSRIA closed system water testing

There are three main components to our BSRIA closed systems water analysis solutions and they are microbiological analysis, physical and chemical analysis.

Our comprehensive suite of closed system analysis tests includes for the following:

Microbiological analysis

Microbiological analysis will test for bacteria commonly found in closed systems, and which can cause problems if left to proliferate.

  • TVC/Aerobic colony count @ 30C

  • Nitrite reducing bacteria (NRB)

  • Pseudomonas bacteria

  • Sulphite reducing bacteria (SRB)

Physical and chemical analysis of water in closed systems

Chemical analysis of the water in closed systems involves an examination of the levels of various parameters of the system water including metals and other substances. We will also review a number of key physical parameters as part of our investigations.

Tests include a visual inspection of the water, checking pH levels, and analysing the concentrations of minerals such as copper, iron, calcium, magnesium, zinc, phosphates, silicates, potassium, aluminium and sodium.

  • Alkalinity as CaCO3

  • Aluminium (Dissolved)

  • Ammoniacal nitrogen as N

  • Boron (Dissolved)

  • Calcium (Dissolved)

  • Conductivity

  • Chloride

  • Copper (Dissolved)

  • Iron (Dissolved)

  • Iron (Total)

  • Magnesium (Dissolved)

  • Molybdenum (Dissolved)

  • Nitrate as NO3

  • Nitrite as N

  • pH

  • Phosphate as PO4

  • Potassium (Dissolved)

  • Silicate as SiO2

  • Sodium (Dissolved)

  • Solids (Settleable matter BG29 & BS 8552)

  • Sulphate as SO4

  • Suspended solids

  • Total dissolved solids (TDS)

  • Visual appearance

  • Zinc (Dissolved)

Other tests can be carried out as required.

Water quality when commissioning closed systems

When a new heating or cooling system is first charged, the water used for filling the tanks will usually be taken directly from the mains water supply. Therefore, the closed system will contain the same levels of bacteria and minerals as are found in mains water.

These levels, particularly the mineral components are not the same across the country and will depend on both geography and where the water is drawn from. Additionally, the expected levels of bacteria in mains water can typically be anywhere between 10 and 100 cfu per ml of water.

Testing water for bacteria

There are many different types of bacteria found in mains water. Enterobacter, Klebsiella and Citrobacter might be found but are very unlikely to live and grow within a closed system. However, as they die off, they can provide a food source for other types of bacteria.

Other species of bacteria which might cause problems in closed heating and cooling systems include Pseudomonas, Flavobacterium, Acineobacter and Aeromonas. These types of bacteria rarely grow into sufficient numbers to cause problems in a drinking water supply. However, in a closed system they can quickly form slime and cause biofilm to form on internal system surfaces including pipework, pumps and heat exchangers. Iron, sulphite oxidising bacteria and sulphite reducing bacteria are also sometimes present in mains water. Iron bacteria feeds off anything ferrous, and can be a cause of corrosion. Red, orange or yellow coloured water is often a clear sign that iron bacteria is present.

A black slime in the system is a signal that sulphite oxidising bacteria are present. If a foul smell is present in addition to the slime, the problem may be sulphite reducing bacteria. This type of bacteria is highly corrosive and can cause serious damage.

How biofilm impacts closed water systems

When a new closed system is first commissioned and brought in to service, slime or biofilm forming bacteria is often the first type to take root. It can coat surfaces with layers of biofilm, which then provide a “hide-out” for other bacteria to start to grow too.

Soon, as the bacteria begins to build-up it will start to have an impact on the thermal efficiency and general operation of the closed heating or cooling system. The layers of bacteria act as an insulation restricting heat transfer efficiencies and also affect the hydrology.

If the biofilm is allowed to grow unchecked, the oxygen levels within the system will become depleted. This in turn allows the growth of potentially damaging bacteria which don’t need oxygen to thrive, such as the sulphite reducing bacteria (SRB).

If water levels in a closed system need to be occasionally topped up with water from an open header tank, then the number of bacteria can be even higher. This is due to the way in which the water is being stored.

If bacteria is not dealt with correctly using specialist closed system water treatment chemicals called biocides, then eventually the entire system may fail… at best its reliability and thermal effectiveness will be compromised.

  • How to select biocides for closed systems

It is equally important to treat the system correctly. Some of the chemicals commonly used to treat water can actually become a bacteria foodstuff if it is not added at the right concentration.

How to sample closed systems

There are no hard and fast rules about how often the water sampling of closed systems should be carried out. The frequency will often depend on the design of the system, whether water quality problems are suspected and its life-cycle stage.

Whatever the type of system (heating, chilled or cooling) or its age, operators should have a detailed plan for the sampling and analysis of the water inside the closed system. The plan should be reviewed frequently as requirements change.

When preparing a sampling plan for closed system water testing, operators should refer to the guidelines produced by both the British Standards Institute (BSI) and the Building Services Research and Information Association (BSRIA). Appropriate safety precautions should also be followed during the sampling procedures.

  • BS 8552:2012 – Sampling and monitoring of water from building services closed systems. Code of practice

Although you will need someone within the organisation to take the samples of water from the closed system, it is unlikely you will have access to the type of specialist laboratory facilities required to carry-out the range of micro and chemical tests specified by BSRIA 50/2015. Closed system water analysis of this nature is best carried out by the specialists such as Water Treatment Services.

Taking water samples from a closed system

Once a suitable sampling point has been identified it should be thoroughly flushed before taking any water samples. The water samples, once collected should be suitably referenced, timed and dated so they can be identified, they should then be sent to the laboratory for analysis. Once the full suite of water tests has been completed you will receive a report detailing the results.

As part of the sampling process there should also be a system for recording and tracking results to allow for comparison over time. In addition to closed system testing for bacteria which can corrode heating and cooling systems, our laboratories can also check for Legionella, metals and other contaminants where these are of concern.

Expert BSRIA water testing for heating, chilled and cooling facilities

Contact Water Treatment Services today to find out more about ourBSRIA  closed systems water testing and laboratory analysis services for the pro-active management of closed heating, chilled and cooling installations.

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specialists we can offer professional, cost effective water treatment solutions across the whole of the UK and Internationally.

Contact us today to learn how our expert water quality analysis services can help you keep your closed water systems in optimum condition.

Contact Us Today

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