Can inhibitor cause problems rather than prevent them?

[Ghandi]

After installing new rads no inhibitor was used, the reason given was that it can cause problems rather than prevent them. The system has been without for approx 4 years now and I've got an Atmos multi boiler, is this advice correct?

thanks.

 

[gassafe]

Inhibitor stops corrosion & sludge build up forming! Or maybe you wanted that in your system lol

 

[Ghandi]

Nope, that's why I'm seeking a second opinion! What course of action should I take in light of what the original advice was?

 

[ShaunCorbs]

Well depends how often you fill your system, new water brings more air which boosts the corrosion

Inh stops this if used correctly and replaced yearly

on a new sealed system with full cleaning done, rads flushed etc won't require inh as there's no air getting into the system

 

[Ghandi]

Well it's certainly not a new system and it does need topping up a few times a year and there hasn't been any inhibitor in for several years, so I'm guessing I need to put some in.

Is it just a case of draining down, bunging some in and refilling, or should I do something else in light of it having none in for a while?

And is there a rule of thumb for dosage - I've read 1L treats 10 rads but I have 15 (some monsters, most average, a couple small), should I use 1.5L and hope for the best?

 

[SteveWannadoGas]

wouldnt have thought that overdosing would do any harm. If in doubt, speak to the manufacturer.

 

[ShaunCorbs]

In short yes and put 2l in won't harm the extra inh

 

[Whyme]

to get heating water to a perfect ph etc etc to prevent corrosion is a specialist job involving various chemicals and testing equipment, out of the remit of your normal plumber/gasman. hence why we put inhibitor in because its virtually done for you apart from the testing to see if its right.

 

[Ghandi]

Ok, so I need inhibitor. In light of it not having any for a while do I:

A) just bung some in
B) drain down, bung some in
C) drain down, cleaner in, drain, inhibitor
D) any other suggestion

Thanks

 

[ShaunCorbs]

b or c depends how much time you have

 

[Frog67]

If your system has been unprotected for 4 years it would be better to clean the system.
If you just dump inhibitor into a dirty/corroded central heating system its not really going to do much.
Take the time and do the job properly.

 

[johnf]

when the new rads/pipework were added was the system flushed? If not then this should be done before adding new chemicals.

 

[Ghandi]

Difficult to tell if the system was flushed as I wasn't present all the time when the work was being done.

My plan...

Drain and flush once
Add x400 (as per boiler makers advice) and fill
Wait
Drain and flush once
Add x100 (as per boiler makers advice) and fill

That sound sensible?

 

[ShaunCorbs]

yes sounds ok

depending on how dirty the system you might need to use x800

 

[johnf]

How about
Add X400
Give it a few days to circulate and work
Drain
Fill and circulate
Drain
Fill
Add inhibitor
The above is the minimum I would do and it obviously depends on how much debris is in the system. A flushing pump and TDS meter would give good results.

 

[Ghandi]

Sadly I don't have access to or the funds for a pump. Will have rely on the cleaner.

How do I decide whether it needs x800 and what will that do that x400 won't? Is it twice as good?!

 

[ShaunCorbs]

depends how mucky the water is coming out if really black x800 if less than choc x400

 

[johnf]

x800 is more of a heavy duty cleaner.

 

[Ghandi]

Hmm, got a feeling I might have to give it the beans and hit it with x800! Wish me luck!

 

[johnf]

Good luck!