Fernox TF1 Compact Fifter

[Johntheo5]

Neighbour called me to have a look at his boiler which required a top up only a week or so after its first service, both the (Baxi) boiler and the filter were installed around a year ago. I removed a panel to gain access to the filter and found a constant drip from under the lid, so isolated it and gave it a little extra nip up with the supplied spanner, leaking still and I wasn't prepared to pull up any harder on the spanner so removed the collar/lid, inspected the O ring, in perfect condition. replaced it and also "greased" the collar threads with some vaseline (all I had to hand), I then just nipped up the collar, the collar was pointing to the "R" on FERNOX and on pulling it up to where its now pointing to, this was a reasonable pull up force but the tightening angle is at least twice that as indicated by the reference marks. I don't know if the service guy removed the lid or not, normally not required? since the magnet can be pulled out and the debris just blown down through the drain, also is it normal to NOT having the marks in alignment?, while this is not important, I'm a bit surprised it takes such a (presumably) greater tightening torque since the tightening angle is much greater. I regularly top up my daughter's boiler and the filter lid collar threads (can't remember the make) don't require any greasing to get a moderate pull up to get satisfactory sealing despite using the same Lid 0 ring for the pat 10 years or so.

 

[Madrab]

For it being Fernox, they are quite rubbish filters. These filters made of the modern fibrous plastic I find to be hit or miss, some leak slightly, some leak quite badly whilst other are absolutely fine. I would have been tempted, if someone serviced it recently to call them back to sort it if it wasn't leaking before they performed the service.

I do use silicone grease and lubricate the seals and lid, makes it much easier to get the lid of for future services if needed. I can only presume that as the lid is now greased it can tighten more but the reference marks are to do with seal compression and it should need any more than that to provide a proper seal but as you have found it doesn't always work.

Wouldn't be the first time I've had to tighten one more than it specifies to get it watertight.