Thermal fluid systems are a better choice for FMs operating industrial laundry equipment but they need regular maintenance to keep temperatures high, says Clive Jones.
01 July 2019 | Clive Jones
In early 2019, two outbreaks of scabies in correctional facilities hit the international news, one in the US at the Women's Huron Valley Correctional Facility, Michigan, the other at Polmont Young Offenders Institution near Falkirk, UK.
Highly contagious diseases such as scabies can more easily spread in facilities where hundreds of people, often in vulnerable health conditions, share the same spaces, such as in hospitals and prisons.
One way to help to prevent the spread of infection is to wash laundry frequently and at high temperatures. Maintaining efficient heat transfer systems is essential when operating industrial laundry equipment in the public sector.
Thermal versus steam
In industrial laundry equipment, fluid-based heat transfer systems are usually used to transport heat, for example, when operating flatwork irons. In this context, thermal fluid systems are preferable to traditional steam-based systems because they easily heat up to 230°C compared with the 180°C of steam-based systems.
Moreover, thermal fluid systems reduce common issues in the laundry industry that would be amplified with a steam-based system, such as corrosion, condensate return and steam trap maintenance.
As a result, industrial laundry equipment used in the public sector requires the use of heat transfer fluids that can work at the correct temperature for prolonged periods of time.
These fluids must have excellent thermal and oxidation stability to prevent the formation of sludge, and must be odourless and non-toxic in case of contamination. However, for excellent performance in the long term, fluids need to be properly cared for.
Planned preventive maintenance
As well as carefully selecting the right type of fluid for industrial laundry equipment, facilities managers should perform sampling analysis every three months to manage the condition of their thermal fluid, reduce costs and to optimise the system's productivity.
A heat transfer fluid's thermodynamic attributes vary according to operating conditions, but all heat transfer fluids will degrade over time, particularly when operating at high temperatures. To keep heat transfer systems in good shape, FMs should undertake regular sampling to establish the condition of the fluid and plan preventative action.
Regular representative fluid analysis and top-ups help to ensure a healthy system while reducing the risk of downtime and decreasing the amount of costly thermal fluid changes. It's hard to calculate the real cost of downtime as it depends on many different factors.
However, according to statistics from 2017, machine downtime costs UK manufacturing £180 billion a year, with 3 per cent of all working days lost annually in manufacturing because of faulty machinery, equating to 49 hours of work and £31,000 for each company.
Heat transfer fluid maintenance and analysis are essential operations that should be conducted regularly, but some plant managers don't realise that there is a problem until it is too late.
By monitoring heat transfer fluids regularly it is possible to detect problems and to take preventative actions that minimise degradation and oxidation, keeping industrial laundry equipment running efficiently and cost-effectively.
Ideally, any plant using heat transfer fluids should operate using a robust maintenance plan that contains regular system analysis, fluid top-up and careful flashpoint and fouling management.
By using thermal fluids designed for industrial laundries, FMs operating laundry equipment can make sure the correct temperatures are reached and by keeping up with regular maintenance. Choosing and maintaining the right fluid contributes to improving hygiene where it is most needed.
Clive Jones is managing director director of thermal fluid specialist Global Heat Transfer