Gas valve with deposits

[kasser]

I just replaced a Baxi gas valve.
Other than old age, any reason why they fail? This one was 6 years old. Seems a bit early to me to fail from wear and tear.
There was a bit of black particles inside but strangely after the fine mesh, so downstream. There isn't a way to bypass that mesh, otherwise it would have been a bit pointless, so would that deposit come from the valve body itself?
I had thought of fitting a filter before the boiler but if the filter within the valve didn't work, any others wouldn't...
I don't think it was the black particles that caused the valve failure. There didn't seem to be enough to block moving parts...

 

[Deleted member 120897]

Maybe dodgy valve? Stuff doesn’t seem to last like it did years ago. I had a job and the engineer before me stated GV, I fitted the one he ordered and it was incorrect. I got Vaillant out under the warranty (boiler was approx 4 years old), needed a new electrode.

 

[ShaunCorbs]

It will be in the pipework / body of the gas valve and it’s down to the oils and the stuff they use to add a smell to ng

 

[kasser]

If it's a dodgy valve, then it did well to last 6 years.
It's not just stuff not lasting, my van these days seem to need filling up more often even though I drive about as much as before. I wonder if the diesel hasn't been watered down like petrol (E5 to E10).

 

[kasser]

It will be in the pipework / body of the gas valve and it’s down to the oils and the stuff they use to add a smell to ng

It's not going to be in the pipework though, if that deposit is after the filter.

 

[ShaunCorbs]

It's not going to be in the pipework though, if that deposit is after the filter.

Anywheres there’s a restriction eg elbows or gas valves it builds up

 

[ShaunCorbs]

If it's a dodgy valve, then it did well to last 6 years.
It's not just stuff not lasting, my van these days seem to need filling up more often even though I drive about as much as before. I wonder if the diesel hasn't been watered down like petrol (E5 to E10).

E10 has half the bang of the old stuff hence why you will fill up double than you used to

 

[kasser]

Anywheres there’s a restriction eg elbows or gas valves it builds up

What I meant is that this deposit is not coming from the pipework, otherwise the fine mesh within the gas valve would have blocked everything. Instead, the deposit is found after the mesh, quite a bit at the outlet of the valve. The mesh itself is fairly clean.

Yes, petrol was diluted recently, but not diesel. Diesel had already been diluted a while back, unless it was done again recently quietly.
I also don't think you need to fill up twice as often. If I remember correctly, e5 = 5% of this bio Rubbish and e10 = 10% so while the quantity has doubled, overall you're moving from 95% petrol to 90% petrol.

 

[ShaunCorbs]

It’s in the oils so they would pass through the mesh and sit / coat the surfaces seen it many a time on the older style gas valves where the castings arnt smooth

 

[kasser]

It’s in the oils so they would pass through the mesh and sit / coat the surfaces seen it many a time on the older style gas valves where the castings arnt smooth

So would a filter before the gas valve help?

 

[ShaunCorbs]

So would a filter before the gas valve help?

No as it would get through as it’s liquid vapour

 

[kasser]

Not much we can do about it then?

 

[ShaunCorbs]

I haven’t found anything

 

[Pssst]

Is it very fine particles almost like pencil shavings? If so it is most likely due to sulphidation deposits on the internal bore of the copper installation tubing which flake off,are carried in the gas stream and eventually mostly get trapped by a mesh filter or gather in the inlet of gas controls.

https://rgii.ie/wp-content/uploads/sites/2/2020/09/TB-0105.pdf