Hydrogen Sulfide Gas in radiators - Advice needed

[Chuck]

Total volume 350 litres seems A LOT for 11 rads.

I suspect he meant 35 litres. He'd need about 2 miles of pipe for it to get up to 350.

 

[Richard4241]

First update. Today my engineer drained the system. We expected to see loads of sludge and contamination, but what came out was really really clean, there was a few small bubbles but no sludge or particles, however still alkaline at 9.0pH. We opened the magnaclean filter, hardly anything in there. After a good flushing, put in 2 liters of Sentinel X400 cleaner. So have to wait 2 weeks now before the next chapter. Also will be fitting a new filter, looking like a Trappex CentraMag 2 (Thanks Rob for recommendation).

Thanks to everybody for the helpful advice offered.

 

[Richard4241]

I suspect he meant 35 litres. He'd need about 2 miles of pipe for it to get up to 350.

Thanks Chuck. Some chump on internet claims 22mm pipe takes 1.5litres per metre. It's actually 0.305 litres per metre. So i'd need 3,762 metres of 22mm pipe - which is slighty over 2 miles!
Also the internet told me radiators take 11 litres per Kw - but i'm questioning that now. Any ideas?

 

[Ric2013]

I had some old-style heavy and solid single panel unfinned radiators in a previous address. Internet claims output would be around 1kW which seems about right. They actually contained 5.5 litres (or was it pints?) each. So much for old radiators being high water content. 11l per kW sound OTT.

 

[Richard4241]

Second Update. I got my system volume totally wrong at 350 litres. Is actually 93 litres. (Thanks Chuck). I've attached a chart for other users to correctly calculate water volume in a system. I've now drained/flushed system again (did contain 2 litres of Sentinel X400 cleaner) and now refilled with 1 litre Sentinel X100 inhibitor. pHlevel at 7. Here's hoping iv'e got rid of the hydrogen gas problem. Will update in a few weeks.

 

[Ric2013]

I'm a bit confused about this hydrogen sulphide issue. H2S would result from the anaerobic decomposition of organic matter, not as a byproduct of the oxidation of iron, which would, I think, be pure hydrogen. I'm not aware that there is any sulphur (S) to be found in a heating system primary circuit unless a bird has pooed in the F&E.

Feel free to shoot me down: chemistry always was my weakest science at school.

 

[Richard4241]

I'm a bit confused about this hydrogen sulphide issue. H2S would result from the anaerobic decomposition of organic matter, not as a byproduct of the oxidation of iron, which would, I think, be pure hydrogen. I'm not aware that there is any sulphur (S) to be found in a heating system primary circuit unless a bird has pooed in the F&E.

Feel free to shoot me down: chemistry always was my weakest science at school.

Hi Rick. Can confirm no bird or any other animal has poohed in my system. It's the rotten egg smell and Sentinel's website that lead me to beleive it was hydrogen sulphide. Since cleaner & flushing, the gassing (whatever it was) seems to have stopped.... so far. Thanks for your comments - sounds plausible.

 

[Richard4241]

Third & Final Update. Problem solved.
System drained (yet again), new magnet/vortex filter fitted then used Sentinel X300 cleaner to get rid of flux from new pipework, flushed out, refilled system and put in 1.5 litres of Sentinel X100 inhibitor.
No more hydrogen/hydrogen sulfide/hydrogen sulphide gas and no more gurgling noises or gas in the system!
Thanks to everybody for their help and advice and hope this thread helps others. Cheers and a Merry Christmas to all.