Gain maximum efficiency from commercial heating products

To gain maximum efficiency from your commercial heating and hot water products, it is vital to ensure they are installed and set up correctly. Commissioning is an important part of this process, with some specifications stating it must be carried by the manufacturer of the products.

But what does the job comprise, what regulations must engineers adhere to and what are the most common issues encountered? We joined our former service engineer Dave, who is now part of our sales team, on a commissioning job to find out more.

Why is commissioning of a boiler important?

During commissioning, the boilers and water heaters are professionally looked at by the manufacturer’s engineers who have in-depth knowledge and experience of the product. But it’s not just the product itself, we’ll look at the whole system. We check if everything is correctly installed and products are working as they should to ensure optimum performance. Any problems will be investigated and fixed.

At Hamworthy Heating, the warranty on parts and labour of our commercial boilers and water heaters is extended by another two years if commissioning is booked with the order. So, that means even if something needs repairing, one of our service engineers will fit the replacement part for free. This gives the customer additional peace of mind.

How long does a commissioning job take?

The average is one hour per boiler module, but it depends on the site and installation. For example, if it’s a building site, you might have to do an induction which can take a couple of hours.

How do you begin a commissioning job?

We carry out pre-commissioning checks first before firing the boiler to see if there is water running through it, check the water pressure and if the chimney is connected. I’ve heard stories of engineers firing boilers and the casing tinkling which was caused by a lack of water in them. They fired a supposedly wet boiler that was actually dry. You really do have to be careful.

We follow a commissioning sheet - basically a commissioning checklist - on which we document everything assessed and measured in the plant room and on boilers and water heaters.

For the commercial boiler system itself, it’s about checking:

  • Pipe connections, to ensure they are installed as per the instruction manual
  • Safety mechanisms, to confirm they are fitted (such as the safety relief valve)
  • System pressure, to make sure it is in a normal range.

In terms of checking the flue system, I assess:

  • What kind of flue it is
  • If it’s the correct size
  • Whether there’s any flue spillage
  • What the damper settings are (if applicable)

And of crucial importance is checking the gas:

  • Does the gas supply look sufficient?
  • What is the gas inlet pressure on the boiler?

To make sure safety features on this boiler are working and a fault code is produced accordingly, I intentionally put a fault on the boiler. In this case [Stratton mk2 commissioning] I stopped the gas supply which is why the fault code E133 will show. I also tested the E164 to see if the boiler is protected if the pump failed. 

From then on, I’m firing the boiler, using the combustion analyser to make sure it is doing so correctly which I can tell by looking at CO2, CO and flue gas temperature readings. These should be in line with what the manual says. In case they are not that would mean incomplete combustion is producing dangerous carbon monoxide.

I can then carry out further testing such as:

  • The gas inlet pressure
  • Air and gas pressure switch settings on the boiler
  • Looking at the flame signal readings in the boiler controller

What regulations and standards must you adhere to while commissioning?

The most important is The Gas Safety (Installation and Use) Regulations 1998 which manifests what the legal requirements are to be able to carry out gas work and what you have to and must not do.

Gas engineers have to be on the Gas Safe Register (official gas registration body in the UK) and retrain every 5 years, get re-tested and kept up to date with changes that have happened in gas safety.

In terms of commercial boiler commissioning itself, there are crucial things we must adhere to, like the ventilation and flueing. If you get these wrong, they are harmful to life, so it’s rather serious.

Once I was on a job at a very well-known site in London. I was shocked when I discovered they had no safety valves on their boilers, which could easily lead to an explosion causing harm to occupants of the building.

To name another example in relation to the gas safety regulations: Gas pipes in non-residential buildings have to be identified as such. Looking at this plant room, I’m able to tell the pipe in the colour of ochre (in accordance with BS1710) carries the gas.

When I enter a plant room, I take a good look, measure and record everything to make sure ventilation is correctly sized and working. As an example, in terms of open flues, you pick things up over the years to get an initial feel for what’s correct just by sight. Sometimes there are plant rooms where you look at a whole wall of ventilation and think “that’s massive”. But then you also have sites where there are just a couple of grills and you think “that doesn’t look enough for the products installed”. Sometimes you know straight away.

In terms of gas safety, what do you pay special attention to?

The system has to be tested before I arrive, a gas purge and safety certificate need to be presented to me.

Then I’m making sure there is enough gas. Despite calculations when the boilers are fitted, the gas supply might not be big enough, especially where an older system has been inherited but not updated to accommodate new boilers or water heaters.

What problems do you most often encounter on a commissioning job?

Sometimes I go into the job where many things aren’t as they should be, meaning there is no way the boiler could actually be fired. Installation requirements vary from manufacturer to manufacturer and there is no uniform approach to a boiler installation - every site is different. In these cases, I will write up a sheet of advisory notes with issues that need to be put right before I can start working on it.

On one occasion, I was on a servicing job at a premium supermarket chain. The boiler had 25 faults on it. I had to explain to the store manager that by pushing the reset button, he had effectively put faults on the boiler. It really is a matter of education with these kinds of things.

Interested in details about commissioning benefits?
Read and book here.