Advice needed for changing heating element gasket

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by neutro »

I thought I was basically done with my Pro 700 repairs from before Christmas, but of course, nothing is so simple.

Since I had to work on the plumbing between the pump and boilers, I decided to pre-emptively replace the brew boiler's heating element gasket, since the original gasket on the steam boiler began leaking the year before.

However I soon discovered that the brew boiler was leaking and caused my kitchen's GFCI outlet to trip. Inconveniently, the leak dripped over the element's electrical connection. The machine suffered no damage though.

I spent the next few days trying to screw the bolts tighter and tighter on the element and pretty soon I was having only a couple of drops upon heating up, probably due to differential thermal expansion (e.g. element expanding faster than the boiler). But at some point, tightening the bolts even more lead to a more serious leak and I had to disassemble everything. I had completely teared the gasket by tightening the bolts too much.

Now I just replaced the torn gasket with the original one which I had kept. But the same scenario is playing out.

Any general hint to prevent leakage while replacing the heating element gasket? I already smeared a silicon-based lubricant on the gaskets before putting them in, but perhaps that was not a good idea. I'll order new gaskets but I wish I could do the right thing the next time! Any advice is appreciated.

Team HB

#2: Post by JRising »

From what you've written, it sounds like you did everything correctly. I'm wondering if something got stuck to either the boiler or the plate of the element and got trapped between the gasket and surface causing the leak. As you already know, they're simple enough to work with. I think you might find some crud stuck to something if you clean and examine the face of the boiler and the section of the element where the gasket sits. If the element's flange has warped, you'd see it.

Put the gasket in place, hold the element firmly against the boiler, finger-tighten all three bolts, then turn them each another half turn in order until snug. The # P9013 ones, the green ones, are so pliable, they're great to work with. It surprises me that one is somehow leaking.

neutro (original poster)

#3: Post by neutro (original poster) »

That was my thinking also. I need to gather the time and courage to remove the boiler again and this time I'll make sure both boiler and element plate are totally clean. I'll also make sure to closely inspect the element plate in case there's a crack or something. I also need to procure new gaskets (I indeed used a green silicone gasket the first time).

Do you know if this kind of gasket can be found at local hardware stores or amazon? Or are those the kind only found at specialized espresso equipment stores? Just trying to avoid $10 shipping fees for a $2 gasket (and I don't see what other part I might need for now).

neutro (original poster)

#4: Post by neutro (original poster) »


Got the new washers yesterday. I brushed and washed both the boiler and the element. Here's how they looked just before installing the washer:

(Inside the boiler, we can see the steel burr -- this is not fiber of any kind. The brown spots are slight corrosion, not dirt).

Installed the washer, using Haynes's Lubri-Film silicon-based lubricant on the washer, boiler and element:

It still leaks, especially when the boiler is heating up. Once heated, it's almost leak-free after tightening the bolts a bit, but it drips during pump operation, and when cooling down afterwards.

I have no idea what I'm doing wrong or what is causing this. The element does not seem damaged in my eyes, but perhaps it is slightly deformed and need to be replaced. The lubricant is also a common factor in my three failed attempts. Perhaps I should not use any, or use another one.

EDIT: just tried without any lubricant, and it still leaks -- I'd say more than before, so that's not the right path. Maybe I have the wrong lubricant for the job.

Any idea welcome as always.


#5: Post by beerwiffle »


Ben Z.

#6: Post by Ben Z. »

Thicker o-ring?


#7: Post by Giampiero »

Watching a photo a just asked myself, there are 1 gasket and 1 oring or it's just a shade effect?


#8: Post by kitt »

Check the element flanges, they can get cracked if you've over tightened the nuts. Profitec also had some differences with element seal thicknesses...on some of the thicker ones they used spacers between the flange and boiler face to avoid warping the flange too much if the nuts were over tightened .

neutro (original poster)

#9: Post by neutro (original poster) »

I don't see any crack in the element flanges... There's only the green silicon gasket, no o-ring. Or is that an o-ring... anyway, just the one. However it seems that the leak is almost always at the same spot (around the same bolt) in all of my tries.

The gasket is pretty thick. When I tighten by hand and then just half a turn of the bolts, there is still a gap visible between the element flanges and the boiler. This gap is probably what is visible as a shade in the photo. It's possible to considerably reduce this gap but it requires tightening the bolts by a lot.

The weird thing is that last year, I changed the gasket on the steam boiler element, using the same green silicon gasket, and it worked on the first try with no hassle.

Next thing to try is perhaps to try and tighten more from the get-go, but I'm running out of ideas apart from ordering a new element.

neutro (original poster)

#10: Post by neutro (original poster) »

So I realized that Haynes' Lubri-Film (Plus) is not really meant for boiler gaskets since it's rated for 210 F max.

So I tried another product (a silicone-based lubricant for plumbing applications such as faucets), and I tried tightening the bolts a bit more from the start.

Well, the boiler still dripped during heating (and pump operation). I tried 3 complete thermal cycles just to see if the problem would fix itself automagically and it didn't. I tightened the bolts a bit more until it began to leak even more, so I probably destroyed another gasket.

I have one more gasket left but no new idea. A new element might be what it takes for some reason.