Case Study: Pipe freezing on heating system 

Pipe Freezing at Airedale General Hospital, West Yorkshire
 
2 x 2.5" Heating Flow & Return Pipe Freezes
 
Location: Airedale General Hospital, West Yorkshire

Pipework: 2.5" mild steel heating flow and return

Freeze duration: 2 hours

 
Yorkshire Pipefreezing Services was contracted to carry out two 2.5" pipe freezes at Airedale General Hospital in West Yorkshire during the renovation of a new hospital ward.
 
The existing heating flow and return pipework needed to be permanently capped off. Pipe freezing provided a controlled method of temporarily isolating the pipes without requiring a wider system drain-down.
 
Before freezing, the heating pumps were switched off and circulation stopped. Freeze jackets were profiled to match the outside diameter of the existing pipework, ensuring effective contact between the jacket and steel pipe.
 
Liquid nitrogen was then used to freeze the water within the pipes. The pipe surface temperature reached approximately -40°C, with the freezes maintained for around two hours while the contractor carried out the works.
 
Once the freezes were established, the contractor safely cut the 2.5" mild steel pipework and installed valves with blanks, allowing the existing heating lines to be permanently capped.
Due to the hospital environment, appropriate precautions were also taken regarding liquid nitrogen vapour and fire alarm detection, with the relevant alarms switched off during the freezing operation.

Result
Both pipe freezes were completed successfully, allowing the heating flow and return pipework to be modified without draining the wider system.
This project demonstrates how professional pipe freezing can provide temporary isolation for commercial and industrial heating systems, particularly where conventional isolation or system drain-down would be disruptive.

Yorkshire Pipefreezing Services provides pipe freezing and live pipework isolation throughout West Yorkshire, Yorkshire and across the UK.