Hydrogen gas in my radiators

[pmx_super]

I had a new boiler installed in April. They apparently powerflushed the system using X800 and refilled with X100 inhibitor.

Ever since then I've found gas accumulating in 2 of the radiators in particular. These 2 radiators also tended to be very noisy, producing a crackling / dripping sound. After much investigation (aided by this site) I found no evidence of air coming into the system, so tried the match-test. Sure enough the gas lit up like a bunsen burner.

I noticed goo floating in my header tank, which I gather might be inhibitor that hasn't been drawn down into the system (it's an open vented system).

What should I do, or rather what work should be done on my system?

 

[kevplumb]

I had a new boiler installed in April. They apparently powerflushed the system using X800 and refilled with X100 inhibitor.

get them back

 

[pmx_super]

I will, but before I do so I'd really like to know what work they should be doing to rectify their previous mistakes.

I'd also quite like to know what they failed to do properly the first time and whether their errors may have compromised the life-expectancy of my new boiler.

 

[kevplumb]

what you mean flush the system properly

 

[pmx_super]

what you mean flush the system properly

So a properly powerflushed system wouldn't exhibit this problem (so soon afterwards), regardless of whether or not inhibitor was added?

I want to understand if this points to them having not actually done a proper powerflush, or if they just failed to get the inhibitor into the system.

 

[Onetap]

I had a new boiler installed in April. They apparently powerflushed the system using X800 and refilled with X100 inhibitor.

Look at the manufacturer's instructions for X800; I think you'll find it has to be thoroughly flushed with clean water and neutralized with an alkali, usually caustic soda. The powerflusher has probably omitted this step, leaving acidic water in the system and causing galvanic corrosion. Test the water with litmus paper if you can get some (Ebay).

X100 will be slightly acidic in normal use; the pH reading is important. You could contact Sentinel for advice.

You need to get this flushed out again and neutralized asap, it is corroding the radiators and leaving sludge in the system. It probably should be powerflushed again. Try the powerflushers company you used, but don't waste time if they argue, just get someone else in, it will cost you less. If it is any bigger than a one man outfit, go straight to the boss/manager, he may have delegated the job to some work-dodging idiot.

 

[pmx_super]

Look at the manufacturer's instructions for X800; I think you'll find it has to be thoroughly flushed with clean water and neutralized with an alkali, usually caustic soda. The powerflusher has probably omitted this step, leaving acidic water in the system and causing galvanic corrosion. Test the water with litmus paper if you can get some (Ebay).

Just re-read the installation checklist - he actually used X400. The sentinel datasheet says that this cleaner has a neutral ph.

 

[Rob]

I cant see any where it says to neutralise the system.

For x400 it says to just flush out before refilling with x100

For x800 it says to flush untill the water runs clear

 

[kevplumb]

you can use X1500000,00000000

if the freakin job aint done right in the first place it wont make any difference

 

[mallyplumbob]

My advice would be to make it a sealed system, should your boiler instructions allow it.
We have stopped fitting open vented boilers because of the problem you are experiencing.
We powerflush thoroughly with X400 and add X100, but have still had problems with magnetite in the boiler heat exchangers in particular
Not so with sealed systems.

 

[onlyfitidealboilers]

you must be fitting the open vent & cold feed incorrectly

 

[nortimax]

Pump running to much and pumping over the header tank causing airation of the system

 

[mickyg]

X400 isnt a powerflushing chemical. It needs leaving in for a few weeks minimum to have any effect whatsoever. Personally I think its next to useless and has only a very mild cleaning effect. X800 is the mildest chemical I use for powerflushing, it doesnt need neutralising and is quite a good chemical IF properly used with heat(min 50c) and a good powerflushing technique. For very bad systems, you need to bring out the bad boys, FX2 or DS40 both of which need to be used with caution.
Anyone using X400 to powerflush wants kicking out the door.
Nothing wrong with open systems if professionally flushed and with properly installed pipework.

 

[pmx_super]

So far the installer has failed to return my calls. I'll persevere, however it strikes me that for the sake of £30 for a bottle each of X400 and X100 I might as well save the bother of bringing back people who don't know what they're doing (or knowingly choose to take shortcuts). It sounds as if the fix is as simple as:

- draining out some water and refilling with a dose of X400
- leave for a few weeks with system operating as normal
- drain system down completely
- refill with a dose of X100

 

[ChrisR]

I'd go for the Fernox Restorer, it's a lot quicker than X400 without needing neutralising. I think it's F3 these days. Leave it in several days.
X800 is great for same day cleaning.