Hydrogen in CH system

[Duncs1]

After reading other posts about bleeding rads, I seem to be bleeding mine every two months or so. Some posts suggested checking for hydrogen and guess what...I had a nice flame firing out of one of the valves. ( Came as a bit of shock to me, I can tell you! )

So, what I need to know now is:

1. How bad are things?
2. How can I correct this?
3. Is there anything I can do to prevent it?

Many thanks for any help you can provide.

Duncan

 

[Hugh Jaleak]

1. Hydrogen and oxide sludge is the result of electrolytic corrosion taking place within the system. Eventually it can sludge up the system, radiators fail to heat, pipework blocks up and the radiators etc rot from the inside out.

2. System needs to be drained, and cleansed. If not too far gone a chemical clean may suffice, if really gunged up then a powerflush might be needed.

3. Once system has been cleaned a suitable inhibitor such as Sentinel X100 or Fernox MB-1 is added. This neutralises the water and prevents the electrolytic corrosion from taking place.

 

[oilman]

You also need to adjust the pH after cleaning to near 8.5. Water is neutral at 7, but this is not the optimum for reducing corrosion.

 

[45yearsagasman]

You also need to adjust the pH after cleaning to near 8.5. Water is neutral at 7, but this is not the optimum for reducing corrosion.

In laymans terms, how would he do that?

 

[D_Hailsham]

You also need to adjust the pH after cleaning to near 8.5. Water is neutral at 7, but this is not the optimum for reducing corrosion.

Never heard that one! Distilled water has a pH of 7 but tap water will vary. The water quality regulations specify that the pH of tap water should be between 6.5 and 9.5.

"Sentinel X100 contains what is known as a pH "buffer". These ingredients in the formulation are designed to actually control the pH level in the water at neutral (approx. pH 7.0), even if the pH level of the incoming water is less than 6.5 or more than pH 8.0."

Boiler manufacturers will also give advice on the quality of the water. For example, Remeha specify a pH of between 7 and 8.5.