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278° Expired
Posted 20 September 2022

Fernox F1 Protector Central Heating Inhibitor 500ml £9.59 Screwfix - free click & collect

Shared by Jonesy_Doo
Joined in 2020

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Protects against corrosion and scale in mixed metal central heating systems to prevent breakdown and premature boiler failure. Inhibits scale, corrosion and sludge. High performance, non-toxic and environmentally-friendly. Stops frequent venting of radiators and prevents cold spots. Reduces maintenance costs and maintains energy efficiency. One bottle treats a 130Ltr system, up to 16 radiators, or 250m² of underfloor heating. Ideal for new and existing systems.
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  1. Avatar
    How do I use this myself? Or do I just give it to the guy servicing the system?
    Basically just tip inside a radiator, a towel one with a top opening where you can funnel it in is easiest.

    You will need to drain the same volume of water out first to make room.

    A downstairs rad, a bleed key and a small bucket or container will help.

    Then just top the pressure backup afterwards .
  2. Avatar
    Interesting, never used this before. Would it actually work? I seem to have a few radiators that either don't warm up well or have cold spots
    Ultimately depends on how bad the system is really. Usually you avoid water changes as the water naturally deoxygenates over time along with the air vent /bleeding, which helps reduce corrosion. A water change means more air in the system due to the fresh water.
    But if the water is like crude oil, it could certainly help draining it down a few times, circulating and getting warm before the next drain down, then adding inhibitor in once happy.
    Obviously certain factors will determine how effective that is, I.e rads on droppers, microbore piping, type of muck in system etc.

    Best advice is run intermittently for ten minutes once every few weeks during summer etc so things don't stick and break in the run up to winter
  3. Avatar
    Are there any issues with mixing different brands of inhibitor?
    No they use the same chemical
  4. Avatar
    Hi all just a heads up this will not clean a system it’s for adding after you have cleaned it
    Yep. This is basically after you've flushed it right?
  5. Avatar
    Good price
  6. Avatar
    I took off every rad in the house a year ago when we were painting the house. I wanted out painter to get in behind the rads and I wanted the rads a fresh white rather than dull beige.

    Good job I did. The stuff that came out was black gunge. That's why I want to throw a bottle of this stuff into the system...who knows when it was last flushed!

    I should have topped it up at the time when the rads went back in but didn't think of it, or know about this stuff.
  7. Avatar
    how werid - on my list to get some of this today, heating system was making noises so thhought i would clean/flush it out and sort. thanks Mr OP
  8. Avatar
    Thanks OP. Grabbed a bottle to add to the system (pretty sure it's already been done but there is no harm in adding more)