My boiler pressure keeps dropping to 0.4bar after a couple of hours even after refilling system to 1.5bar. There is no visible sign of leaks or water discharge on the boiler, pipes, radiators and pressure release drain pipe. Any ideas on possible causes and fixing it.

Dinesh, February 2010

Strangely enough the problem seem to have been
solved by by fitting a straight connector-joint on a
radiator supply pipe on the first floor although
there was no apparent sign of leak on this pipe.

Many thanks to Richard and Taz for your pointing
in the direction of possible causes which I greatly
appreciate.

Dinesh, March 2010

your problem sounds like you have a leak under the floor is it a solid floor (screed )and your pipes are in it .or are the pipes on drops from above ,the first step i would take would to isolate the boiler once you have pressurised it up by turning off the two valves underneath the boiler if it loses pressure you know it is a problem within the boiler

richard, February 2010

any central heating pipes under floor boards (ground floor ) or in concrete floors, it has to be going somewhere, strange one there

taz, February 2010