Room for improvement
How one hotel upgraded its heating to meet consistently high demand while reducing its energy use.
Operating on a 24-hour basis and consisting of 14 floors, Novotel Reading is a modern hotel, located in the centre of this large town. Owned by Accor, a multinational hospitality company, the hotel was put forward for a replacement heating system in 2018 to increase the reliability of the system and breathe new life into the building. Installation experts Tech Asset Management was quick to recommend Potterton Commercial and its Sirius three range of commercial boilers for an efficient and accessible solution.
Situated next to the Novotel is another Accor hotel (an Ibis), with both buildings sharing a combined plant room on the top floor. As such, the single plant room is tasked with serving around 361 rooms, a restaurant, and a leisure centre featuring a sauna, steam room and a heated indoor swimming pool.
With this in mind, it was important to opt for a commercial heating solution that was able to meet a consistently high demand and keep guests comfortable at all times, while also maximising efficiency and adhering to Accor’s environmental responsibilities.
Used for heating and hot water, the existing plant room had contained four 500kW steel-welded tube boilers which were 13 years old. At the time the project got underway, only one out of the four boilers was functioning effectively, and even this boiler was having the occasional breakdown and demonstrating issues with hot water temperatures.
Ben Reeson, contracts manager at Tech Asset Management, was keen to try the new Sirius three range when he was challenged with this particular project as it would provide an efficient solution. The boilers would be used to deliver heat for the site’s air handling units (AHUs), fan coils and domestic hot water (DHW).
He says: “We downsized the existing boilers slightly, reducing the whole plant by 1000kW. As such, we decided to install four 250kW Sirius three floor standing boilers in a cascade arrangement. The hotel is able to operate on one boiler a day, meaning that each boiler can share the wear and tear.”
Ultimately, this investment provided the hotel with a long-term solution as the boilers are a lot more likely to have an increased life span if their workload is significantly reduced, creating savings across the board.
Given that the combined plant room is located on the 14th floor of the hotels, one of the key challenges of the project was removing the existing boilers and getting the new boilers in place effectively and without disruption. It was therefore essential that both sets of boilers could fit in the lift and be manoeuvred easily, improving installation.
Reeson says: “The old boilers weighed around 350 kilos each, and there was no equipment readily available to help remove them from the building, which posed a problem as it instantly made it more difficult to transport the products. Luckily, we were able to use the ramps which had been delivered with the Potterton Commercial boilers to get them safely out of the plant room and into the lifts.
“We’d initially set aside a day to position the new boilers on site by lifting them up to the plant room. However, I was pleasantly surprised to find that the Sirius three boilers came with castor wheels and a ramp. With this addition, we were able to finish the positioning in record time by 11:30am – saving time, money and effort.”
With downtime not an option for a hotel facility, which has a continuous demand for heating and hot water and needs to remain in constant operation, the team at Tech Asset Management ensured that one of the new boilers was installed and piped up in one day by using a temporary flue arrangement. For a period of around four days, the single boiler was able to run the whole hotel while the team piped up the remaining three boilers.
The existing skid had a main boiler with a flow/return header, so the main pipework was taken back to the header, leaving the main header in position due to the condition of the pipework. The skid was then extended to accommodate the new boilers.
Given that there is a 24/7 heating and hot water demand, the boilers’ wide 9:1 modulation ratio reduces constant on/off cycling to improve efficiency and boiler longevity. A gross seasonal efficiency of up to 97.5% reduces energy consumption while a stainless-steel heat exchanger helps to ensure systems cleanliness for ultimate reliability.
Reeson adds: "We chose these floor standing boilers as they occupy a very small footprint considering their power output, which is a major benefit, and they were very easy to install and commission. The boilers have lifting hooks and wheels on the bottom so we just rolled them off the pallet and into position using the supplied ramp. This enabled easy access over a step in the plant room and saved us a lot of time and effort. The boilers were narrow enough to fit through a standard door, which made getting the boilers into position for installation a cinch.
“The new HMI (human machine interface) was easy to programme with a clear menu system, and it also has a built-in cascade controller which was pretty neat and easy to use. Commissioning was quick and simple.
“On all of our projects, we perform a major and minor service on an annual basis to gauge how the systems are performing. The Novotel system had a major service in September 2018 and based on combustion figures everything was running well.
“While the boilers are monitored externally, I have visited the site on a regular basis since the installation to check that everything is running as it should be. It’s positive to note that all the boilers have had the same number of burning hours and are working as efficiently as possible, meaning the cascade arrangement is working correctly. We’re really proud of the Novotel Reading project and are using it almost as a blueprint for other hotel projects we have in the pipeline.”