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Andrew Smith
Andrew Smith, Plumber
Category: Plumbing
Satisfied Customers: 3757
Experience:  City and Guilds qualified plumber
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I have just replaced 2 radiators on a combi boiler system.

Customer Question

I have just replaced 2 radiators on a combi boiler system. The work involved small alterations to pipe work as inlet/outlet pipes are located in different positions. The system was working fine before I drained it. Radiators were not attached to system for about 2 weeks while decoration work took place. On refilling the system I am losing pressure quite quickly (2 to 3 hours from 1.5 bar to effectively 0 bar). Boiler works fine until pressure falls below 1 bar. I have search everywhere for a leak but both radiators are on the ground floor and I have been able to look at all the pipework in the void below the floor and there is not even a drip which points to the pressure escaping from the boiler. All radiators have been bled to within an inch of their lives and have no air in at all. The boiler itself is not expelling water through the safety overflow pipe. I am at a loss with regard to what to try next. Any ideas?
Submitted: 4 years ago.
Category: Plumbing
Expert:  Andrew Smith replied 4 years ago.


Can you tell me how you drained the system?