Can you break a gas valve with LDF?

[dan_the_plumber]

Hi all, I serviced a boiler last week, adjusted the gas valve (a tiny little tweak) then gave a tiny little skirt of LDF on the test points.
Just had to go back there and boiker only running on half. I think one of the sololoids on gas valve is not opening.
Question is, thus just co-incidents or have I shorted the coil out with LDF?

Thanks a lot...Dan

 

[SimonG]

Depends how hard you hit the gas valve with the can!

 

[Darren Jackson]

Hi Dan, It could be coincidental yes but you cant be 100% sure. Personally I never spray inside a boiler due to the electrics in there, Instead I always use the brush on LDF or my sniffer if I've got the FGA out, whenever electric is nearby.

 

[dan_the_plumber]

Is there a different kind of LDF available? I think someone said something about one that’s like a gel?

 

[Darren Jackson]

Is there a different kind of LDF available? I think someone said something about one that’s like a gel?

I've only ever heard of the spray can LDF or the bottled brush on type of LDF myself. Never come across a gel type LDF. Maybe someone else knows of it and has used it. Be interesting to find out.

 

[dan_the_plumber]

I do sometimes just use a brush. Perhaps I’ll go back to that method. The boiler is a fairly old Worcester 28i RSF combi. It won’t go to max flame.
Both of the leads on the gas valve will fire the boiler when only one is connected. But when they are both connected the boiler still only fires on minimum. It must be the gas valve gone right?

 

[Darren Jackson]

Loose connection, bad earth, Gas Valve or PCB, time to get the multi meter out mate.

 

[Best]

No idea what chemicals LDF actually is made of, but I am warned by an electronic engineer friend that I shouldn't use most cleaning or lubricating sprays near electrical coils or boards.
(I tended to use WD40 to clean oil burners etc)
The solenoid on oil burners can be damaged just by a little Kerosine as had that happening.

 

[dan_the_plumber]

No idea what chemicals LDF actually is made of, but I am warned by an electronic engineer friend that I shouldn't use most cleaning or lubricating sprays near electrical coils or boards.
(I tended to use WD40 to clean oil burners etc)
The solenoid on oil burners can be damaged just by a little Kerosine as had that happening.

I might have learned this lesson the hard way I think. Although the boiler is 12-14years old and is pretty much due for a change anyway.

 

[Chuck]

No idea what chemicals LDF actually is made of.

We used to use the same recipe that was used for blowing bubbles at kids parties when I was a nipper and dinosaurs roamed the earth. IIRC, two-parts water, one-part glycerol and some Fairy Liquid.

 

[Aire]

Fairy liquid? Isn't that now banned for use as a source of leak detection due to it been corrosive?

 

[Chuck]

Fairy liquid? Isn't that now banned for use as a source of leak detection due to it been corrosive?

Quite possibly, who do you think banned it? Neat Fairy liquid is AFAIK, both slightly caustic (cuts through the grease) and contains salt (as a thickening agent) but one only needs a couple of drops per litre so it's very dilute when mixed up. Anyway, that was decades ago, when we did/used many things that aren't allowed now.

What the OP was actually wondering was what is in LDF and all the ones I'm aware of are basically water, a surfactant to reduce the surface tension so bubbles form easily, and a thickening agent (like gycerol) to increase the viscosity, which stabilises the bubbles and makes them live longer.

 

[dan_the_plumber]

It turned out this gas valve’s adjuster had broken. Little bit strange as I managed to get desired max/min pressures on service. Then 5 days later the gas valve went up the wall!
Anyway, I fitted new gas valve and now boiker running fine.

 

[JusKel]

I've come across that when servicing boilers that haven't been adjusted in a while. Usually happens while there. Readings pull in good then drift off again.
There was a leaflet with one valve which suggested they only have a 10 year lifespan anyway.

 

[dan_the_plumber]

I've come across that when servicing boilers that haven't been adjusted in a while. Usually happens while there. Readings pull in good then drift off again.
There was a leaflet with one valve which suggested they only have a 10 year lifespan anyway.

Nice one for this. I thought I’d done something wrong. As I said I did manage to get the proper burner pressures, but then the valve broke a few days later...Ce Strange, no?

 

[Gold Gas]

It's that horrible problem that happens every now and then.
You've serviced the boiler and now it doesn't work.
Can't be helped! - i personally get a blob (technical term) of ldf on my finger and blob it in the test point.

I explain that these checks are vital and now the boiler is working correctly at the proper pressures etc, and it can't handle it and was always going to fail. The main point is, its burning correctly and they are safe.

 

[dan_the_plumber]

It's that horrible problem that happens every now and then.
You've serviced the boiler and now it doesn't work.
Can't be helped! - i personally get a blob (technical term) of ldf on my finger and blob it in the test point.

I explain that these checks are vital and now the boiler is working correctly at the proper pressures etc, and it can't handle it and was always going to fail. The main point is, its burning correctly and they are safe.

Yeah good point, you need to be able to carry out maintenance on a system and/or a boiler otherwise it wasn’t up to scratch anyway

 

[Gazzzz101]

You can definitely break a Worcester 30i erp has valve with ldf - trust me I’ve done it