How to Add Inhibitor to a Central Heating System - Quick and Easy Method

In this plumbing guide i will show you how to add inhibitor to a heating system! If you want to learn DIY plumbing basics, then this guide is for you and you wont believe how easy this method is. This video will show you how to make yourself a free tool to inhibit your central heating system and get the job done with no plumbing skills required. Protect your heating system now!
Tools i recommend for this job below:
⚪ Plumb Tub - amzn.to/4afBkMu
⚪ Inhibitor - amzn.to/3vyTiJK
⚪ Radiator Bleed Key - amzn.to/3NlaLLX
⚪ Adjustable Spanner - amzn.to/3TgI4A8
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[@jayseabie215]

Alternatively if you have a towel rad in your bathroom just pour it in the top with a funnel, no need for that fancy tool. Also no carpet to get wet either!

[@TheDIYGuy1]

Yeah your right however this is a more generic method in a sense as not everyone has towel rads

[@geoffcarlton4047]

Came here to say this, so much easier

[@stuartday1876]

This is what I do too.

[@BarryBulsara576]

The highest radiator in the house, or doesn't it matter?

[@anyat686]

I thought the magnetic stick 🧲 thing went into bathroom towel rail. ?

[@allancopland1768]

I add inhibitor via my FERNOX TF-1 magnetic separator. It's far less palaver. No messing around with rads.

[@manitobaMOOSE44]

Once again thank you for another amazing video, I very much appreciate all your help on our DIY jobs 👍🏻😎

[@TheDIYGuy1]

Very welcome

[@paulturner9958]

what a bloody marvellous video. Sort of thing everyman should know.

[@MansurMoinoddin]

Thanks for your supporting video

[@fostexfan160]

Best vid I've ever seen on the subject!. No boring introductions or explanations, straight into it and very professional. Well done

[@michaelricks1618]

A really great tip and wonderfully clear explanation and demonstration. Excellent video camera work and editing, too! Thanks so much for sharing.

[@alanwallis2467]

Great video. As always,easy to follow and understand. I've never done this job before but I will now. Thanks 👍👍

[@TheDIYGuy1]

Glad to help. Thanks

[@timniven9461]

Probably one of the most useful tips I've seen in a while. Thanks ..

[@TheDIYGuy1]

Glad it was helpful!

[@tilerman]

This is what youtube was made for. Bloody brilliant stuff, cheers mate!

[@amazing451]

I think this has to be one of your best tips yet Cameron. Great video, see you soon.👍👍

[@TheDIYGuy1]

Awesome! Thank you!

[@neilmckie2768]

I have to say, mate, that you bang out some excellent videos. I've found loads of useful info which I've put to good use, so thank you very much

[@TheDIYGuy1]

Your welcome 🙏

[@CL55AMG]

Best DIY video I've seen in ages. Clear and easy explanations, plus definitely making up one of the filling pipes, which is far better than the plastic one I purchased. Look forward to seeing more videos. Great job 🙂

[@TheDIYGuy1]

Glad you enjoyed it! Thanks

[@kchello6533]

I put inhibitor to my heating system last month. Instead of making a special tool like yours, I pour the inhibitor direct via the vent of the towel rack in my bathroom, the vent holes of towel rack are usually at the top rather at the side, hence we can pour the inhibitor without any special tool. Firstly, I drained the water in the towel rack down like you did, then poured the inhibtor into the rack at the top with the help of a small funnel. This could be a simpler method to most layman like me.

[@TheDIYGuy1]

Yep for those with a towel rad this is the way

[@thedeadpres]

Undoing the bottom connections would stress me out too much, I'd probably just get narrow flexible hose and use the siphoning principle to the water out (measuring of course). Then there's less chance of post-filling leaks.

[@johnchampion7819]

I agree with all of tye comments below - a very good video with clear explanations of what is going on. Your channel is a great help to all of us DIY plumbers.

[@TheDIYGuy1]

Much appreciated!

[@conradsmith7752]

Love these tips and short cuts. Reminds me of the series of short programme in the eighties that provided tips for DIYers and tradesmen

[@MrMadenuff]

Excellent video, thank you.

[@Buckleyswoodturning]

Why are the best ideas so simple?👍

[@GpoppaJohn]

Really good demo. Thanks

[@TheDIYGuy1]

Glad you liked it!

[@meeruisland]

I am happy with plumbing, but i have to add if i was not i would come here, your steps and guidance are so simple to understand and showing the piece of the rad would help others some fly by these yours are perfect

[@CJTODAY85]

thank you, for that tip sorted several ie inhibitor and dropping rad forward to paint behind..

[@cprog]

Thank you for great tips!

[@TheDIYGuy1]

Glad it was helpful!

[@YNWA-oq5uf]

Top man!!! When I learn anything new regarding plumbing tips it makes me smile you sir are so generous sharing info keep up the good content. New Subscription added

[@TheDIYGuy1]

Thanks for subscribing and glad to help

[@dodgyjpt]

Another great video very easy guide to follow

[@TheDIYGuy1]

Glad you think so!

[@geralldus]

Excellent, thank you.

[@tenbear5]

Very good, thanks 👋

[@sevenodonata]

Plumberparts and The DIY Guy - both everyday nice guys 👍

[@TheDIYGuy1]

Thanks. James’ channel is brilliant too isn’t it. Hoping to collab together this year

[@herbetone]

Yet again, many thanks for a great video.

[@TheDIYGuy1]

My pleasure!

[@andrewhenderson3914]

Great video, very well explained and useful to know.many thanks.

[@TheDIYGuy1]

Glad it was helpful!

[@soyabean911]

Brill vid, and a quality plumber. Very informative, expertly explained and demonstrated. 👌🏼

[@TheDIYGuy1]

Glad you enjoyed it

[@matthewhill7946]

Top video gezza, With your help watching this and other ones I've managed to help my mom with her changes to her new bungalow, renovated bathroom kitchen and the living room so thanks again 10/10

[@TheDIYGuy1]

Your welcome 🙏

[@george9710]

Clever little tool! You could use a funnel ( you can get one that has a plastic flexible hose at the end ) but it's a lot messier than what you showed so I'll be making one of these for sure!

[@Falco45able]

Thanks for the tip fella , did exactly that today, stay lucky, stay safe! 😉

[@TheDIYGuy1]

Thanks, you too!

[@TK42138]

Excellent video.

[@davidbridge3542]

Ive been doing this task for over 40 years and its always good to watch someone else show their method. Spot on demonstration. Ticked every box for me. Well done. Ps I might have used a tank connector in the bottle cap ??

[@TheDIYGuy1]

Thanks a lot. Yep a tank connector would work a treat

[@glenbraithwaite7767]

as normal clear,precise,and to the point instructions!! ....top man😊

[@TheDIYGuy1]

Glad it helped!

[@lnby]

Great tip and video bud. Another way is adding inhibitor via the magnetic filter hopper which most have these days. I plan to remove my sludge filled rads in the summer fkr w good clean thanks to your videos.

[@TheDIYGuy1]

👍👍

[@TeeTee-zm2re]

​@@TheDIYGuy1do a video on how to clean magnetic filter?

[@farukm7627]

Thanks again, Mate.

[@nowthenad3286]

That was brilliant. Thank you

[@TheDIYGuy1]

Glad you enjoyed it!

[@cassimvorajee2847]

Very informative. Thank you.

[@TheDIYGuy1]

Glad it was helpful!

[@lesdrinkwater490]

Great tips thanks.

[@TheDIYGuy1]

No problem!

[@simonchilli2088]

Great stuff. We live in an area where the water is quite high in limescale. The rads have been bled but the ones up and downstairs furthest from the boiler are quite cool even when the heating is full on. We'll be giving this a go very soon.

[@ME-hc1fk]

The water in a radiator or heating system has nothing to do whatsoever with LIMESCALE !!!

[@PHNX0]

Thats what the same number of turns on the lock shield bit is about. Research ‘radiator balancing’. You restrict hot flow to the rads nearer your boiler by closing the lock shields on them a bit, so that hot water makes it to the furthest ones. This guy has a video on it! kzbin.info/www/bejne/bX_Wi2WaZ7SoptUsi=ZzQqzzByU0wtTIN_

[@scottishwildridez]

Absolutely awesome guy, brilliant stuff love your videos

[@TheDIYGuy1]

Thanks a lot!

[@tonybilco1317]

Great video more plumbing like this please ❤

[@TheDIYGuy1]

Will do!

[@GameboyAA]

Great job this one really helped me 😊

[@TheDIYGuy1]

Glad it helped!

[@q9home1]

A marvelous tools, thank you.

[@TheDIYGuy1]

👍

[@MrGuido63]

Thanks DIY Guy, Very helpful advice and clear instructions. BTW, the tattoos look great! 😊

[@TheDIYGuy1]

Brilliant, thanks

[@secret_one]

Again another super tip, thank you.

[@TheDIYGuy1]

My pleasure!

[@stephenmaskrey6527]

Great video alway wondered how to do this bit of DIY

[@macbook9084]

What a great video Thank you!

[@TheDIYGuy1]

Glad you enjoyed it!

[@Johnboyjws]

superb video thank you

[@TheDIYGuy1]

Glad you liked it

[@alangriffiths6469]

Very interesting!

[@mikeonfreeserve2926]

My wife would like to adopt you. She remembers watching videos with plumbers. 😮

[@terrywalker4733]

Hi. Many thanks for this video very useful information.

[@TheDIYGuy1]

Glad it was helpful!

[@michaelplays2449]

Great video !!! thank you

[@TheDIYGuy1]

Glad you liked it!

[@thomassheridan4252]

Great idea going to make one 👍

[@TheDIYGuy1]

Go for it!👍

[@teknisijamet]

Awesome, how can you think of this amazing idea 👍

[@jonnyallen1232]

I use a garden weed sprayer, put an adapter on the end pump it into the top of a rad or filling loop job done

[@denniscarvell1828]

Good vid ,well thought out for non plumbers.

[@TheDIYGuy1]

Thanks 👍

[@shaza3602]

Very helpful Individual

[@TheDIYGuy1]

Glad it was helpful!

[@jonbretro4596]

Interesting approach. I simply isolate the header tank (vented system), drain the tank, then chuck the inhibitor in the tank and open the isolation valve.

[@MalcolmJames-sg3zg]

What a great video , Thanks very interesting ,

[@TheDIYGuy1]

Glad you enjoyed it

[@federalagent420]

just what i needed

[@AJBTemplar]

Excellent

[@sydsnott5042]

Excellent videos. Im an avid fan of the Adey Pro MagnaClean. Simplicity itself to introduce an inhibitor to the system. No need to touch a radiator. Just drain off some water from the boiler. Remove the top of the Adey Pro and pour straight from the bottle into the Adey Pro chamber. Using an inhibitor and the Adey Pro my system is ultra clean. The yearly inspection/service clearly shows this when the Adey Pro top is taken off and on the 'magnet' there's nothing and the water in the system is almost drinkable.

[@TheDIYGuy1]

👍 thanks for sharing

[@bobtahoma]

Everyone should install one of these. They pay for themselves in no time.

[@PHNX0]

Just seen your comment after writing the same method myself. My plumber showed me how to do it (before he moved out of the area). As you say, simplicity itself.

[@stanlee5766]

This is a really good way of filling up with inhibitor thank you. You mentioned the “balancing of the radiators” how do you do this please. Thanks.

[@rizimirza8190]

I love your videos so much my dear ❤

[@jesterwaterwizard2917]

Brilliant thank you

[@TheDIYGuy1]

You're very welcome

[@sajulldin5147]

Great video

[@TheDIYGuy1]

Thanks 🙏

[@philscholes6225]

Great video and super helpful. One question, what size connection is on the end of the flexible tap connector to allow it to screw into the radiator?

[@adrianoakes152]

I have a towel rad so easy for me but I do agree this is a great idea.

[@TheDIYGuy1]

Yes! Thank you!

[@jansmit4628]

Using the normal used filling position would also work. Connect the filling hose to the CV side and fill the hose from the other end with the inhibitor fluid, then connect it to the closed water fill tap which you use for normal filling. Open the tap a little, then open the valve on the CV side. The inhibitor will be pushed in the CV system, followed by regular tap water. No special tooling needed and no possibility on radiator leaks at the end.

[@StephenLarkin]

Legend. Love the work you do. Clear and consise. Any rule of thumb on how many Radiators one litre will cover?

[@TheDIYGuy1]

1 litre will do you for around 10 rads. If more, go with a second bottle

[@johnadams1976]

Great video. I did exactly this in the summer when I took every radiator outside and cleaned them out! 24 rads!!! Remember, 1 bottle of inhibitor might not be enough... They say how many rads they typically do on the bottle. Also remember it doesn't last forever.... I usually drain my system, replace the inhibitor and top up with new water every 3 years.

[@TheDIYGuy1]

Thanks for sharing 👍

[@BarryBulsara576]

Out of interest -- I know it's a how long is a piece of string question -- how much do you think a plumber who have charged you to remove 24 rads, clean them out, refit and balance the system? I wasn't aware they needed cleaning that often, mine haven't been done at all in 17yrs, so I'm a bit concerned now...Although, never had any dramas with them.

[@privatenoone8911]

Today's radiators are too thin and restrictive . Old radiators (Mison style? ) never needed cleaning or inhibitors. Parents house central heating still working after 50 years when we sold it after they passed.

[@straty5598]

​@@BarryBulsara576That's a lot of radiators, Buckingham palace by any chance?

[@Subgunman]

The optimum liquid to refill the system with would be deionized or distilled water. Also there is no reason one could not use automotive radiator fluid in the system. It too has rust inhibitors in it. It might be cheaper than a specialized radiator inhibitor.

[@hrhsii2]

Nice concise video. Can you take some water out using the hose outlet on the boiler filling loop? Then top up using a towel radiator if you have one?

[@ak0792]

Handy thank you

[@TheDIYGuy1]

Your welcome.

[@absaly]

many thanks

[@TheDIYGuy1]

Welcome!!

[@iainhunneybell]

Nice trick 👍

[@TheDIYGuy1]

Thanks

[@gerardatkinson1622]

Great video really helpful, and the cap on the flexible pipe priceless

[@gavinphilip2698]

Excellent video, can i add to any radiator in the system?

[@Mr.0.007]

What a great video, and Lad,.

[@TheDIYGuy1]

Thank you kindly!

[@johnrobertson1829]

all the years as a heating engineer i never once counted the turns on the return valve, it was always ach that will do it. good job pal

[@TheDIYGuy1]

Thanks 😊

[@richardhanley1342]

He’s only trying to help the inexperienced people like myself

[@richardhanley1342]

Not everybody is a heating engineer

[@johnrobertson1829]

@@richardhanley1342 your point?

[@johnrobertson1829]

@@richardhanley1342 I'm not discrediting his work by any means, read my message I praised him.

[@Paul_Holmes]

Nice one, even easier using the towel radiator if you have one 🙂

[@TheDIYGuy1]

Yes, true 👍

[@maleka58]

Thank done 🙏🙏

[@TheDIYGuy1]

👍👍

[@Doug....]

Thats a clever catch tray. I could have done with that on many occasions. Save messing up the roasting trays 😄

[@TheDIYGuy1]

Hah absolutely

[@jnoonanuk]

Hi great video! Perfect for what I need. I'm replacing a radiator and need to add inhibitor, i was gonna add a 1 litre bottle? Us that too much, would 500ml be better? Can you add too much? How much is too much? Thanks 😊

[@paulhealey2984]

I poured anti freeze into the header tank in the loft. Easy.

[@alanproctor9316]

To refill the rad, i usually only open the TRV until it's filled then open the lockshield, as for the filling tool, i used a fitting for the rad blank to copper then upright to a 54 x 15 reducer as a funnel.

[@neilmoore260]

like your videos,very helpfull and make the jobs easy. i have a vaillant boiler that i cant leave on,as it fills its self up and f23's every time. could you do a quick video on what could be happening,as getting bored keep draining some water out everytime i have a shower!! would be greatly appreciated, from a long time subscriber Neil.

[@musyorable]

It’s brilliant video thank you. How often we need to add inhibitors?

[@TheDIYGuy1]

Welcome. Yearly 👍

[@MrGuy999guy]

Brilliant

[@mikeywatson7171]

Not sure about Sentinel, but most other brand bottles are the same size as an AdBlue nozzle thread. Then a couple turns of PTFE on the spigot side and it fits snugly into the rad thread 👍🏻

[@TheDIYGuy1]

Interesting 👍 cheers

[@jimm675]

Thanks for the great vid. Just to make sure I get the correct flexible connector what size is the fitting that screws into the rad where the bung is? Cheers

[@TheDIYGuy1]

Your welcome. 1/2 inch

[@moirani2021]

💯💯💯💯well done Sir

[@TheDIYGuy1]

👍👍

[@googlecontrolled]

If you have an F&E tank you do need to do something! You should have kept some inhibitor back to add to the tank which has replenished with untreated water to prevent stagnation and biofilm build up. Fernox used to include it in the instructions on a gallon tub of MB1.

[@Mike_5]

A nice way to do this is to add extra height pipes above the height of your radiators in your home upstairs connecting to the Flow and Return Central heating pipes maybe in an Airing cupboard with a connection to attach the additive and a air release valve

[@TheBuckspygmy]

I just drained the radiator and used a syringe to inject the inhibitor left by removing the bleed screw. Tedious but it worked.

[@jimp1646]

Great video. A boiler engineer has offered to top up my inhibitor by injecting it directly into the boiler. I've not had it done that way before so wasn't sure if that's a good idea. Are there any advantages to me topping it up via a radiator instead. I have a pressurized system. Any advice would be appreciated.

[@bernardmanners9657]

Great video and keep them coming, but would probably have been better to use a radiator without radiator extensions on it, as to the uninformed this may of been confusing

[@TheDIYGuy1]

Thanks. Fair point

[@bernardmanners9657]

@@TheDIYGuy1 ....but I will still be stealing this hack 😁👍

[@TheDIYGuy1]

Hah run with it 😊

[@bobbeardall1910]

I have a caravan with a combo boiler which has anti freeze in the system, can I top up the concentration when needed using this same method?

[@Pete.Ty1]

👍👍👍. Thank you

[@TheDIYGuy1]

Welcome 👍