Morning Folks,
I drained and re-filled my central heating a few days ago, adding a litre of Fernox F3. (150 litre boiler so 2 x 500ml bottles of Fernox).
Due to a deflated expansion vessel, we’d been refilling via the filling loop on an almost daily basis for a long time so the system has only had water in it for ages with no inhibitor - not good! EV has been recharged now so pressure is stable.
Anyway - the system has been running absolutely fine for the last few days and I’ve signed up for an ongoing care plan with Baxi. However, they can’t come out to service the boiler for about five weeks. (I suspect it hasn’t been serviced in years).
I was planning to drain out the F3 and flush the entire system one more time with just water before a final drain and then refill adding one litre of Fernox F1 inhibitor.
I had hoped to do this a couple of days before the service (foolishly assuming they would come out within about a week or so). As it’s going to take five or six weeks, I’m wondering whether this is now going to be too long.
I’ve read differing opinions on how long F3 can stay in the system.
The bottle’s label (which common sense tells me is the one to pay most attention to) says up to one week for heavily sludged systems.
I have no real way of telling whether or not the system is heavily sludged, given its lack of maintenance over the years. All of the radiators very warm from top-to-bottom, so I suspect not.
A local plumber / heating engineer told me to leave it in for ’a few weeks’, one or two people online say ‘indefinitely’ (although I wouldn’t leave it in permanently).
Given that the system probably hasn’t been flushed or serviced in years, is 6 weeks likely to be too long? We live in a 'very hard' water area.
(11 radiators of varying sizes which have all been plumbed using 10mm plastic (barrier?) pipe).
Cheers.
Alex
I drained and re-filled my central heating a few days ago, adding a litre of Fernox F3. (150 litre boiler so 2 x 500ml bottles of Fernox).
Due to a deflated expansion vessel, we’d been refilling via the filling loop on an almost daily basis for a long time so the system has only had water in it for ages with no inhibitor - not good! EV has been recharged now so pressure is stable.
Anyway - the system has been running absolutely fine for the last few days and I’ve signed up for an ongoing care plan with Baxi. However, they can’t come out to service the boiler for about five weeks. (I suspect it hasn’t been serviced in years).
I was planning to drain out the F3 and flush the entire system one more time with just water before a final drain and then refill adding one litre of Fernox F1 inhibitor.
I had hoped to do this a couple of days before the service (foolishly assuming they would come out within about a week or so). As it’s going to take five or six weeks, I’m wondering whether this is now going to be too long.
I’ve read differing opinions on how long F3 can stay in the system.
The bottle’s label (which common sense tells me is the one to pay most attention to) says up to one week for heavily sludged systems.
I have no real way of telling whether or not the system is heavily sludged, given its lack of maintenance over the years. All of the radiators very warm from top-to-bottom, so I suspect not.
A local plumber / heating engineer told me to leave it in for ’a few weeks’, one or two people online say ‘indefinitely’ (although I wouldn’t leave it in permanently).
Given that the system probably hasn’t been flushed or serviced in years, is 6 weeks likely to be too long? We live in a 'very hard' water area.
(11 radiators of varying sizes which have all been plumbed using 10mm plastic (barrier?) pipe).
Cheers.
Alex
