For a business known for its heated pools and guest comfort, reliable boiler performance is not optional. At Warmbaths, A Forever Resort, two coal-fired boilers sit at the heart of daily operations. However, the resort was battling with inefficiency, as well as high coal and chemical consumption.
When one of the boilers was opened for inspection, it was obvious that corrosion and scaling were already taking their toll. Significant capital had to be spent to bring the boiler back to an acceptable standard. Forever Resorts engaged Allmech, leading local supplier of boilers and water treatment solutions, to review the water treatment setup and provide a second opinion.
Investigating the root cause
When Allmech assessed the site, a demineralisation plant was supplying feedwater to the mid-pressure coal-fired boiler. Allmech Managing Director Lionel Maasdorp explains that, on the surface, highly purified water may seem like the ideal choice. However, “clean” demineralised water absorbs minerals from whatever it comes into contact with. In a carbon steel boiler system, that can accelerate corrosion in the boiler shell, tubes and condensate lines.
“Considering the water was being used for a mid-pressure coal-fired boiler, we did not agree with the demineralised water,” Maasdorp says. “Water that clean can be corrosive in the boiler and pipes.”
Low pH levels compounded the problem, particularly in the condensate lines, where oxygen-related corrosion was evident. Steam traps were clogging with rust particles. The resort was in the process of replacing some metal pipework with PVC to mitigate the effects, but when the boiler was opened and it was clear that acid wash and repairs to boiler tubes were required. Forever Resorts decided to relook their system requirements and setup and asked Allmech to step in.
A change in strategy
After analysing the incoming raw water, Allmech recommended discontinuing the demineralisation process and instead repairing and optimising the site’s softeners. This reduced unnecessary chemical expenditure and allowed for a more appropriate treatment strategy.
The team then started using Allmech A103, a blended boiler treatment designed for mid-pressure systems.
Maasdorp says that A103 performs several functions simultaneously:
• An oxygen scavenger removes dissolved oxygen.
• A pH booster stabilises and elevates alkalinity.
• A polymer keeps suspended solids in suspension so they can be removed through controlled
blowdown.
• A vapour-phase component carries over in the steam to protect condensate lines from corrosion.
Allmech also implemented weekly check-ins to monitor how the new approach was working. Total dissolved solids (TDS) were monitored, blowdowns adjusted, and chlorine and pH levels in the condensate tracked closely. Over time, test results began to shift in the right direction and pH levels increased. Rust particles in the feed tank decreased, while corrosion stabilised.
Visible results
When the boiler was opened after the first year under Allmech’s treatment programme, visible corrosion had already reduced. Maasdorp says some debris remained, but this likely originated from previously damaged condensate lines.
The original equipment manufacturer recommended another acid wash. Allmech did not believe this was necessary, but the procedure was carried out.
At the most recent inspection, the difference was clear. “The tubes were spotless,” says Maasdorp. “There was only evidence of old scale that had flaked off in a hard-to-reach area. There were no signs of excessive corrosion, and the particles that had previously been present in the feed tank were no longer there.”
A clean boiler eliminates the need for further acid washing – a harsh and destructive process. Avoiding these interventions extends the lifespan of the asset.
Operational impact
For Jean Nel, Boiler Manager at Warmbaths, the improvements have been significant.
“We saw a lot of changes. The boiler was more sufficient, with less coal usage,” he explains. “There was less corrosion in the boiler and less scale detected on the inner tubes from the time Allmech took over the boiler water treatment.”
The resort has also seen improved chemical efficiency compared to its previous setup and Nel believes the risks to longevity have been effectively addressed.
“Without a good water treatment partner, you can damage your boiler and tubes. It can cause a lot of damage in the long run,” he says. “The value of Allmech’s service is up to standard. They are always a phone call away and always there to assist us. We can say with an open heart we are happy to have them on our side.”
A partnership approach
Maasdorp is quick to credit the site team for their role in the turnaround. “I am always proud when a client’s team works well with our staff. A good team working together helps to look after a company’s assets and livelihood by reducing unnecessary costs.”
With the right treatment strategy and disciplined monitoring, boiler water chemistry becomes an asset protection tool rather than a recurring repair risk.
About Allmech
Allmech was founded in 1995 and has grown over two decades to become one of South Africa’s leading boiler manufacturers and suppliers to the water treatment industry. Allmech offers a comprehensive range of electrical, gas and oil-fired boilers with water treatment to suit.
With a customer base stretching from its head office in Benoni, Johannesburg, throughout Southern Africa and beyond, Allmech has become recognised as an experience end-to-end provider for clients requiring boiler plants, steam supply of all types, cooling towers, water treatment equipment and associated chemical programmes. Aside from sales to direct and distributor clients, the company’s services include technical support, repairs and maintenance, and spares sales.
Allmech is also the only authorised South African agent for Runxin valves, produced by the global Wenzhou Runxin Manufacturing Machine Co., headquartered in China.
For more information, visit www.allmech.co.za
