The pressure dropped to 0 on my Worcester- Bosch condenser boiler. I have managed to increase the pressure by adding water to the system but would like to know if I should be adding more Fernox? System was installed 18months ago and had Fernox protector put into it then. Thanks in advance for your advice.

Pam, May 2009

Hi! After posting this question i put pieces of toilet paper round each of the pipes in my house and found out that the water was VERY SLIGHTLY leaking from the pipe joining onto the TRV. I tightened up this nut, it only moved a tiny amount, but nonetheless it moved, and hey presto, no more dropping pressure. I've added a couple of nails to some radiator water, but so far no sign of rust! So thanks for your advice and no, I don't need to add more protector!!!! Cheers!

Pam, June 2009

Agree with mr k answer. However you have probably got a slight leak on your heating system. There are two types of leak, positive and negative. Positive leaks occur when water is pushed out of the system, this can clearly be seen by corrosion on pipework , valves fittings etc. Negative leaks are harder to spot as they are caused by air being sucked into the heating system due to return pressures on the pump drawing water around the system and sucking air through any defective joints etc.
happy hunting.

Fido, May 2009

Not necessary again if you have not drain the system since than. you can check content of fernox by drawing some water from radiator air key in glass and put some mild steel nails in water, if get rusted in two weeks than you need to add fernox in it.

Mr K, May 2009