If the system’s dirty, start with a central heating treatment that matches the job. Use a cleaner or flush for debris and sludge, then add an inhibitor once it’s clean. The usual mistake is buying the wrong bottle for the stage you’re at - a cleaner won’t protect a neglected system, and inhibitor alone won’t shift heavy muck.
Corgi Universal Cleanser - 1L
1 litre concentrate cleanser for heating systems
Sentinel X400 Sludge Remover - Rapid Dose 300ml
High performance cleaner for older central heating systems, 300ml Rapid Dose.
Adey MC3+ Central Heating Cleaner - Rapide 300ml
300ml Adey MC3+ central heating cleaner for all systems, quick-dose, clears slud…
Adey MagnaClean MC3+ Cleaner - 500ml
Cleans central heating systems, removing magnetite and sludge to restore efficie…
Fernox F3 Central Heating Cleaner - 265ml
pH-neutral central heating cleaner for commissioning, 265ml
Fernox F1 Central Heating Express Protector
400ml Fernox F1 Express aerosol inhibitor against corrosion and limescale
Sentinel Leak Sealer - 1L
1 litre white leak sealer for minor leaks in indirect central heating systems
Sentinel X700 Biocide - 1L Clear
1 litre non-corrosive biocide for underfloor heating systems
Adey Procheck Refill Kit - 2 Pack
Refill kit for Adey ProCheck digital water test (2 pack)
Adey MC1+ Central Heating Inhibitor - Rapide 300ml
Quick-dose 300ml inhibitor for central heating corrosion protection
Start with what the system needs, not the label on the bottle. A central heating treatment only makes sense once you’ve worked out whether you’re dealing with a clean fill, a dirty system, or a job that needs both stages. On a modern condensing setup, system and flue compatibility comes first. Then look at filtration, fuel type, and who’s actually signing it off, especially where Gas Safe fitting applies. One treatment can suit one install and be wrong on another. That is where call-backs start.
If the system is dirty, you are usually choosing between a central heating cleaner, a central heating flush, or a central heating descaler. Cleaner and flush products suit sludge and general contamination. A flush is the harder option when you need to shift heavier deposits before refill.
Descaler is the one to use where scale is the main issue. It will not cover every poor-running system. Once the water is clean, a central heating inhibitor is the normal follow-up because it protects the system rather than cleaning it again. On Central Heating, that is the main split: clean first if you need to, then protect it if you want to avoid the same call-back.
What you buy usually comes down to the state of the system and how much time you have on the job. A central heating treatment for a routine top-up is a different call from a central heating cleaner or central heating flush on a system full of muck. A central heating inhibitor only makes sense when you are protecting clean water rather than shifting deposits.
The common mistake is grabbing the cheapest bottle and expecting it to do two jobs. If you are also picking up fittings or sundries, Central Heating Accessories is the usual next stop. If the job runs into boiler-side parts, Flues & Boiler Accessories is where that decision sits.
Once you’ve picked the treatment, the next question is what the system needs around it. If the install is full of sludge, start with a central heating cleaner or flush before you leave inhibitor in place.
On older systems, sort the filter at the same time. It helps stop the same muck moving back through the circuit. If you’re changing pipework or the boiler side as well, check the related accessories and flue parts before you sign it off. Jobs stall there when the main unit is right but the rest of the kit isn’t.










