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Fernox F1 Central Heating Inhibitor (REVIEW)

Fernox are among the top manufacturers of boiler filters and central heating chemicals. Within their range is the Fernox F1 central heating inhibitor.

Fernox central heating inhibitor is designed with two core goals in mind:

  • Break down existing iron-oxide from the insides of radiators and pipework
  • Protect the insides of pipes and radiators from further iron-oxide build-up

Fernox F1 Review

Central heating sludge is a huge killer of boilers. A combination of a boiler filter and central heating inhibitor such as F1 can help combat heating sludge and protect a boiler for years to come.

A typical new boiler being installed on a sludge infested system and without a filter or inhibitor may only last 18-24 months.

A correctly protected with both a filter and inhibitor, regularly serviced boiler will last 7-10 years or more.

Of course, step 1 is to purchase a boiler filter. Fernox offer a range of high quality boilers filters, being their TF1 filter range. Filters are priced at £80-120 plus installation cost.

The second the filter is installed, it will start to remove sludge from the system. But, it’s important to ensure that the system is dosed with inhibitor.

Without the inhibitor, some stubborn heating sludge will stay stuck to pipework and radiators.

How Much Fernox F1 Inhibitor is Needed?

A qualified engineer will be able to ensure the correct level of central heating inhibitor is added (Fernox also sell an inhibitor test kit). A rough guideline is 500ml for every 8 radiators.

For small properties Fernox offer F1 Express 265ml. And for larger properties, they offer the standard F1 inhibitor which comes in a 500ml tub.

Other benefits of Fernox F1 Inhibitor

  • Fernox suggest that adding a filter, F1 inhibitor and F3 cleaner will result in cost savings of up to 15%
  • This relates to direct energy use and doesn’t account for the prolonged life of a boiler
  • Having problems with air locks in your rads? This could solve the problem
  • Reduces the chance of sticking pumps and excess boiler noise
  • Reduces central heating maintenance costs

Alternatives: MagnaClean MC1 and Sentinel X100

MagnaClean and Sentinel both offer a similar protector/inhibitor in their chemical range.

There’s almost nothing in it price wise.

Review Verdict: Which is The Best Central Heating Inhibitor?

You can buy Fernox F1 Inhibitor here.

Any qualified heating engineer will agree that Fernox, MagnaClean (Adey) and Sentinel are all trusted brands in this space. There’s nothing in it.

For warranty purposes, it’s always worth going with own-brand products. So, if you’re having (or, already have) a TF1 filter fitted, stick with the Fernox F1 protector.

Likewise, if you are using a Magnaclean product, go with the MC1.

Most gas fitters fitting Worcester boilers will lean towards the Sentinel X100, as Worcester Bosch don’t produce their own brand heating inhibitor (but, they do produce system filters).



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