How do i add Central Heating Inhibitor?

theLearner_3

evening all,

i want to add some central heating inhibitor into my sealed central heating system - but i want to check i'm doing it right (before getting myself into a mess :mad: )

1) close the TRV to 0 and close the lockshield valve noting its original position.

2) remove this air vent pin completely



i plan on using a product called Sentinel X100 Concentrate which comes with a plastic tube that (i'm hoping) slots into the hole left by the air vent pin

3) Empty 1 tube of Sentinel into the radiator.....then i'm unsure of how to bleed the remaining air out of the radiator/system

Should i just replace the air vent pin, then re-open the TRV and the Lockshield valve and vent the air out later on (air normally finds its way to either the bathroom or one of the bedroom radiators)?

1 final question - should i drain the system down from the boiler using the Drain Valve before doing this (and then re-pressurise the system using fresh water) ?

any help will be greatly received.

timmyevo

hi,

what boiler do you have? if it has a filling loop, then use the supplied filling kit. all you need to do is remove 1 end of the filling loop and inject via this. make sure the 1 way valve is in the correct position though or it will be a wet mess.

failing that, you can do it the way you are describing but its messy

Canucklehead

Hi
How about

Turn off valves at each end, open vent to lose pressure,
Crack rad valve union and drain a couple of litres of water.
Take out vent fitting ,leaving you with a half inch hole in which you put a short length of hose ,funnel in the end and pour in 1 litre of sentinal . Cheaper than the concentrate in a gun.
Refit vent, open valves, vent air and switch on c/h.
Any good?

Corgi Guy.

theLearner_3

timmyevo wrote: »

hi,

what boiler do you have? if it has a filling loop, then use the supplied filling kit. all you need to do is remove 1 end of the filling loop and inject via this. make sure the 1 way valve is in the correct position though or it will be a wet mess.

hi - it's a Glow-worm 30ci Plus.

Not ure about a filling loop, looked in the user manual and couldn't see this mentioned. Not sure if this clarifies things but you drain the boiler down through a drain valve and you fill it using what they (Glow worm) refer to as a filling device - a threaded plastic tube that opens and closes like a normal tap

theLearner_3

Canucklehead wrote: »

Hi
How about

Turn off valves at each end, open vent to lose pressure,
Crack rad valve union and drain a couple of litres of water.
Take out vent fitting ,leaving you with a half inch hole in which you put a short length of hose ,funnel in the end and pour in 1 litre of sentinal . Cheaper than the concentrate in a gun.
Refit vent, open valves, vent air and switch on c/h.
Any good?

Corgi Guy.

thanks for your reply - i'm getting some concentrate for free which is why i'm using that :money:

presumably because i'm adding a smaller quantity of concentrate compared to the oridinary stuff, i don't have to drain much water out of the radiator.

would you advise draining the boiler (which is easy to do because it's right next to our kitchen sink) and then refilling it with clean water or is this pointless considering the overall total capacity of the system?

Canucklehead

Hi


Drain out a little less from the rad,no need to do anything with the boiler.

Just out of curiosity how long has the system been running with no inhibitor?

Corgi Guy.

theLearner_3

the complete system was installed in the summer of 2004. i cannot confirm if inhibitor was put in originally as we bought the house in august 2006. judging by the dark colour of the water in the system i would guess not unless its lost its effectiveness.

Re a different issue with the same system that i pm'd you about ages ago now (pressure going ski high when the central heating was switched on) the problem was being caused by a blocked pipe in the boiler (what looked like a short metal braided hose, the engineer was using all sorts of things to try and clear the blockage - seems to be working ok now though fingers crossed)

Canucklehead

the complete system was installed in the summer of 2004. i cannot confirm if inhibitor was put in originally as we bought the house in august 2006. judging by the dark colour of the water in the system i would guess not unless its lost its effectiveness.

Sounds to me like no.Sealed system water should be quite clear. I asked the question as usually I would associate putting inhibitor in a system with either draining most of the water out ,or after a flush. Adding it at this stage will leave all the gunk in the system but should halt further build up. Maybe in the summer you could flush and re- inhibit it.

Re a different issue with the same system that i pm'd you about ages ago now (pressure going ski high when the central heating was switched on) the problem was being caused by a blocked pipe in the boiler (what looked like a short metal braided hose, the engineer was using all sorts of things to try and clear the blockage - seems to be working ok now though fingers crossed)

This would seem to be the result of the system having no inhibitor.The flexi hose from the system to the expansion vessel blocked creating the same condition as having no pressure in the vessel.

Corgi Guy.

theLearner_3

i think i'll add inhibitor now to prevent further build up as you say and then drain the whole system in the near future. to flush it do you simply drain the system through the lowest point (bottom of a radiator downstairs) add a central heating cleaner, re-fill and drain again after leaving the CH on for a while?

thanks for the excellent advice

Canucklehead

Hi

Drain down, put in x400 and leave it for a few days with heating on as you would normally use it ,drain , fill ,drain, fill... as long as it takes for it to run clear.
Inhibitor.
If you do some research then you might feel like hiring a Powerflush machine from HSS for example.

Corgi Guy.

theLearner_3

i added the concentrate yesterday - what a messy job.

isolated the radiator and drained off quite a bit of water from the radiator by opening the lockshield valve connection to the radiator.

injecting the concentrate in through the tiny hole left by removing the air vent pin didn't work all - the hole very quickly became blocked. I removed the 22mm nut around the air vent pin and i didn't realise that entry into the radiator itself was 90degrees off from the 22mm hole. Trying to lodge the applicator into this hole and then adding the concentrate wasn't fun :mad: Removing the 22mm blanking nut at the opposite side did make getting it into the system a little easier though, but i ended up with the stuff everywhere!

Won't use the concentrate again - but thanks for all your help Canucklehead :money:

By the way the water was proper dirty but i'm hoping i've stopped it getting any worse. Seems strange that someone would install a brand new system and then not add any protector to look after it.