Ptfe or not

Wearb

It's a bit quiet here, so I have a question. Should I use ptfe on the threads of a new immersion heater or just let the washer do it's job by itself?

slavetothegrind

i would use some tape as it can help with later removal by minimising corrosion between the two metals

PTFE and fernox lsx(especially for unvented)

Dtp1979

Wearb wrote: »

It's a bit quiet here, so I have a question. Should I use ptfe on the threads of a new immersion heater or just let the washer do it's job by itself?

Ptfe and uniwhite. Or a fine layer of flax and uniwhite

K.Flyer

Uniwhite (Boss in old days) on both sides of the fibre washer and a bit on the threads.
Carefully clean the threads and surface of the immersion boss and hand tighten fully home.
Fully tighten using a box spanner.
Been doing it that way for over 30 odd years without an issue.

Wearb

Thanks folks for all the advice. I can't get the old one out. I have an 18" stilson on it (tank still full), but afraid to put too much force on it in case I cause damage. I have shocked it with a hammer, but not a budge.

Would it help if I heated the water in the cylinder with the coil?

What holds the threaded boss in the cylinder? If it's solder, then I can't take a blow lamp to it.

Cerco

Wearb wrote: »

Thanks folks for all the advice. I can't get the old one out. I have an 18" stilson on it (tank still full), but afraid to put too much force on it in case I cause damage. I have shocked it with a hammer, but not a budge.

Would it help if I heated the water in the cylinder with the coil?

What holds the threaded boss in the cylinder? If it's solder, then I can't take a blow lamp to it.

Have you tried a cylinder spanner with a piece of steel pipe over the end to extend the handle and give greater leverage?

I would not use a stilson in case of slippage, but I could be totally wrong.
I have only ever replaced two elements.

Dtp1979

Wearb wrote: »

Thanks folks for all the advice. I can't get the old one out. I have an 18" stilson on it (tank still full), but afraid to put too much force on it in case I cause damage. I have shocked it with a hammer, but not a budge.

Would it help if I heated the water in the cylinder with the coil?

What holds the threaded boss in the cylinder? If it's solder, then I can't take a blow lamp to it.

No it's never solder. I've never not been able to budge one with a hammer. There'd be a bit of spring in the Stilson. Use an immersion spanner and hammer that

K.Flyer

Wearb wrote: »

Thanks folks for all the advice. I can't get the old one out. I have an 18" stilson on it (tank still full), but afraid to put too much force on it in case I cause damage. I have shocked it with a hammer, but not a budge.

Would it help if I heated the water in the cylinder with the coil?

What holds the threaded boss in the cylinder? If it's solder, then I can't take a blow lamp to it.

You could keep pressure on it using the stilson and give the stilson a sharp tap with a hammer about half ways along which might shock it out. (I have had to use that method myself)
You could try using a blowtorch and just put some heat for a minute or two around the boss where the immersion goes into the tank.
Safety First; Clear the area of all flammable items and have a fire extinguisher to hand.
Then repeat with the stilson and hammer.
Personally I prefer the box spanner with extra leverage, but sometimes you have to use the debt collector stilson.

Dtp1979

K.Flyer wrote: »

You could keep pressure on it using the stilson and give the stilson a sharp tap with a hammer about half ways along which might shock it out. (I have had to use that method myself)
You could try using a blowtorch and just put some heat for a minute or two around the boss where the immersion goes into the tank.
Safety First; Clear the area of all flammable items and have a fire extinguisher to hand.
Then repeat with the stilson and hammer.
Personally I prefer the box spanner with extra leverage, but sometimes you have to use the debt collector stilson.

I think everyone has one of those in the van. Mines a 30"

Mutha

I use Uniwhite both sides of the washer. Have had to use heat on a few stubborn ones.

Wearb

Ok I got it eventually. I had been tapping the stilson without success. (Don't have a proper immersion tool) I put on the coil heating and turned the stat right up. When hot I kept pressure on the stilson and tapped it with hammer. Also had "customer" tap around the immersion and stilson jaw with a hammer. It eventually gave. It gave me a fright too, at first I thought it was the piece in the cylinder that moved.

I don't know if heating the cylinder helped. Perhaps if I had gone at it with as much conviction first time I would have shifted it then.

Thanks for all the advice. Time to get paid now. Coffee and biscuits. ( The joys of working for siblings).