I descaled my boiler by soaking the entire thing in citric acid, but I couldn't remove the BSV so I left it on. In hind sight, that was a mistake because the spring reacted badly with the citric acid and the oxidation left a bunch of black carbon-like residue all over the inside of the valve. I cleaned it up, but now the BSV is hissing after only turning the machine on for 2-4 mins and the boiler pressure gauge indicates it's not even 1 bar yet.

Can I just replace the spring (if so who sells BSV springs) or do I need a whole new BSV? My understanding is that these things are calibrated to release at 2.5 bars, so getting a new spring might not be sufficient. Espressoparts has generic BSV for $20-30, but 1st-line has the manufacture specific one for $60. Can I just use the generic?

Chances are better that there is some crud in the valve seat causing a steam leak, rather than a problem with the spring.

I took a quick video here:

dougd wrote: Espressoparts has generic BSV for $20-30, but 1st-line has the manufacture specific one for $60. Can I just use the generic?

The generic should work fine if the thread patterns match. If you have questions or concerns ask espresso parts.

So, let the boiler come up to full pressure and, on the way to this, manually activate (fully) the safety valve with a piece of wood. If you're lucky, this will clear out "some crud in the valve seat causing a steam leak, rather than a problem with the spring."

If you replace the valve, replace the copper washer sealing the valve to the soldered hex beneath it. But you really need to remove the valve before ordering a replacement because it is either threaded 1/4" BSPP or 3/8" BSPP and its hard to know w/o removal. The size of the soldered hex could be a clue but it can also fool you.

erics wrote:So, let the boiler come up to full pressure and, on the way to this, manually activate (fully) the safety valve with a piece of wood. If you're lucky, this will clear out "some crud in the valve seat causing a steam leak, rather than a problem with the spring."

I depressed the valve with a wrench on its way to full pressure. As soon as full pressure was achieved, I released the wrench, and there was a strong discharge of steam. Scared me for a second.

erics wrote:If you replace the valve, replace the copper washer sealing the valve to the soldered hex beneath it. But you really need to remove the valve before ordering a replacement because it is either threaded 1/4" BSPP or 3/8" BSPP and its hard to know w/o removal. The size of the soldered hex could be a clue but it can also fool you.

Any tips on removing the valve given that it's soldered on? When I had the boiler off, I put a crescent wrench on the valve, and hit the wrench with a hammer so that it would turn CCW, but even that didn't loosen it up.

dougd wrote:Any tips on removing the valve given that it's soldered on? When I had the boiler off, I put a crescent wrench on the valve, and hit the wrench with a hammer so that it would turn CCW, but even that didn't loosen it up.

wholly crud!

You need TWO wrenches. One would be a flat wrench like used on bicycle hubs that are double-nutted to lock the bearing adjustment in place (a Cone Wrench), or other similar flat wrench that will fit the braze-on fitting. Then a large wrench (or another flat wrench) for the valve. Place them so all you need to do is squeeze the two wrenches together with one hand. That nearly eliminates torque on the boiler's fitting....

Excellent! That did the trick. This is why I love HB.

You are lucky you did not twist the fitting on the boiler. Best practice when taking anything apart on an espresso machine is to use two wrenches. One on the boiler (or other fitting) for support and the other on the nut or other part you are removing. When working with the pipe fittings it is best to use a tubing wrench. They resemble a box end wrench with a cut-out for the wrench to slip over the tube. That adds support around the tube and gives you more even pressure which prevents the tube from twisting.

cannonfodder wrote:..... When working with the pipe fittings it is best to use a tubing wrench.

Commonly referred to as a "Flare nut wrench":