Closed System Testing

Closed System Testing | Heating System Analysis | Protect your Heating System

Closed System Testing Analysis


Regularly testing your closed heating or cooling system for microbiological and chemistry levels ensures your system is under control and is a preventative task that helps reduce risk of system failure, corrosion, scale, poor flow and bacterial growth. All of which can help reduce large bills to repair inevitable system failures if no testing is carried out. Such testing can help identify sufficient chemical inhibitor levels such as Molybdate and Nitrite. 

uRisk is a nationwide water hygiene company with City and Guilds trained engineers who have experience in industrial, commercial and domestic heating and cooling systems.

How often should I Test my Closed System?


Closed System Testing frequency is carried out every 3 months (quarterly) or when a system has changed where there is new or additional pipework.

How long does Closed System Testing take?


Closed System Testing can take up to 1 hour depending on the design and heating system you have installed.


What happens after the Closed System Testing Results


Once you receive you Closed System Testing Results you will be advised on the next steps to take. In most instances you will be advised to have your system dosed with either inhibitor and/or biocide. You may also be advised that further Closed System Testing is required to interpret how the inhibitor and/or biocide has impacted your system.

How much does Closed System Testing cost?


Closed System Testing prices may vary depending on the size, quantity of your systems and site requirements, but industry prices generally range between £100 to £400 per system test.

Microbiological Testing/Analysis

Aerobic Colony Count

Nitrite Reducing Bacteria (NRB)


Sulphite Reducing Bacteria (SRB)

Chemisty Testing/Analysis

Visual appearance

Suspended Solids

Phosphate as PO4

Alkalinity as CaCO3 (Automated)

Iron, Ferric (Filtered)

Calcium, Dissolved

Aluminium, Dissolved


Solids, Settleable

Nitrate as NO3

Ammoniacal Nitrogen as N

Boron, Dissolved

Copper, Dissolved

Iron, Dissolved


Silicate as SiO2


Iron, Total

Boron, Dissolved

Magnesium, Dissolved

Potassium, Dissolved

Total Dissolved Solids

Nitrite as N

Sulphate as SO4

Iron, Ferrous (Filtered)

Molybdenum, Dissolved

Zinc, Dissolved

Sodium, Dissolved

How to make my Heating System or Cooling System more Efficient?


New systems are often higher more efficient systems heating systems and cooling systems due to technology upgrades. But how do we keep our heating systems and cooling systems efficient; and how do we make old and existing heating systems and cooling systems last longer?

Preventative monitoring and servicing can play an important role in avoiding large bills for faults and replacement costs for heating and cooling systems. Below are just a few ways you can avoid those unwanted expensive bills:

  • Designed correctly and fit for purpose
  • Installed correctly
  • Cleaned & commissioned correctly
  • Maintained correctly

Failure to ensure any one of these 4 items will results in poor system performance, a reduce system lifetime and more expenses.

What happens if I do not treat my Closed System?


Systems that are not treated at least annually (commercial systems bi-annually) will begin to suffer from scale, corrosion, and gassing can occur as well as the potential for microbiological proliferation. System efficiency can see up to 30-40% reduction in system efficiency on sludgy and fouled systems.

Are uRisk qualified?


Yes, all of our Legionella Risk Assessors at uRisk are Legionella Risk Assessment qualified and accredited by City & Guilds and can help assist you in meeting compliance today for HSE (ACoP L8). uRisk is Safe Contractor and Construction Online approved so you can rest assured that you are working with a trusted water hygiene service provider who put health and safety first.

All uRisk engineers are DBS Checked to ensure suitable people are entering your premises and to safeguard vulnerable people.

Our booking process

Get a Quote

To get a quote you can phone, email or complete our ‘Get a Quote!’ form to receive a quotation within 24 hours.

Book an Appointment

Once you’re happy with your quote we’ll confirm a suitable date and estimated time of arrival for your appointment.

Your Appointment

An engineer will be with you on your scheduled date, and will call you prior to arrival (when safe and possible).

Report & Support

Our team will quality assess your report for PDF distribution, typically within 2-10 days of the site visit.

All payments are due prior to booking completion unless agreed in writing for 30 days from the date of invoice. We will hold your booking time for 24 hours whilst we wait for payment.

Download the HSE Legionella Guidelines here for FREE


Why choose uRisk?

25 Years Experience

Over 25 years of water hygiene and legionella control experience.

Customer Service Excellence

Friendly and simple advice by phone, email & online at your convenience.

City & Guilds Qualified

All staff are trained water hygiene consultants and engineers.

Nationwide Coverage

With engineers located all across the UK, we’re never too far away.

UKAS Accredited Testing

Our labs are UKAS approved providing you with quality assurance.

Full Compliance Services

Your one stop shop for legionella control, no need to go elsewhere.

Contact Us

01462 419444

Head Office:

Baldock Herts SG7 6NG


Monday to Friday:

0900 - 1700

Offices Closed for Lunch:

1300 - 1400

Water Hygiene Services

Extremely happy with our legionella risk assessment carried out by uRisk, easy to understand and great customer service. Thanks again
Nickayla Robertson
Nickayla Robertson
21:22 15 Jan 19
Brilliant service! Thanks a lot for the hard graft
Leon Macauley
Leon Macauley
21:12 15 Jan 19
Brilliant Service, efficient, professional, punctual and friendly.
Alex Windsor
Alex Windsor
18:21 15 Jan 19
uRisk have been helping us with our Legionella Control for a number of years now. We've recently had a CQC audit and they were very impressed with our legionella compliance! Thank you for all your help.
Mike Port
Mike Port
20:41 07 Aug 18
Fantastic training courses and we've found the legionella risk assessment very easy to read and far more detailed than any we have previously had. 5 star service!
Gemma Pond
Gemma Pond
20:37 07 Aug 18
Incredibly detailed and professional team. Have been beyond helpful with with our CQC legionella compliance for our Safety. They’ve found solutions to fit around how we work and our budgets. We are always advised with reference to HSE which has been brilliant.
Amy Thorne
Amy Thorne
20:29 07 Aug 18
We're a small GP practice and started using uRisk for legionella risk assessments. We opted to use their remedial and monitoring services and they've been absolutely great. We cannot recommend them enough! Thank you so much!
Amanda Pates
Amanda Pates
18:30 07 Aug 18