Hello all,

Trying to revive an Astoria machine: The safety valve is brand new, but leaks steam when the boiler is heating. I have the pressure stat all the way low, so it should trip easily, but when the machine heats, it leaks from the safety valve too much far before the pressure stat trips. Could it be a bad safety valve? The display (no actual pressure gauge) reads 1.2 bar, or similar, so I'm guessing it's the pressure stat. It looks to work physically, but could the spring be too tight? I can actuate it manually, but it looks to require a great deal of force from the pressure bladder. I suppose I'll order up a pressure stat to give it a shot. Also, I did check the lines from boiler to pressurestat - They are now perfectly clean.

Any thoughts or comments would be greatly appreciated, Thanks!

The membrane and small passages in the pressurestat can have scale buildup. Have you tried descaling it with 50/50 white vinegar to water? You can bring it up to pressure, let it cool, back up to pressure, let it cool several times to force that solution into the pressurestat. Then rinse many times to get rid of the vinegar taste. I'm suggesting vinegar because it won't form a precipitant.

If you are actually getting ~1.2bar boiler pressure the Safety Valve should not be opening! They are usually set to release @ 1.8 or 2 bar and are usually marked accordingly I believe. So either getting a false pressure reading and pressure stat is going too high or if pressure is really around 1.2 bar bad new safety valve.

The display (no actual pressure gauge) reads 1.2 bar . . .

What display? A pic or pics would be worth a thousand words.

It has an LCD screen (shown in pic). The pressure readout seems slow to catch up, but it was at 1.0 or 1.2 when the safety valve started spewing. I replaced the old one because it was very corroded from constantly leaking. I'm confident the pressure in the boiler is there, (maybe even too high), but the pressurestat does not want to actuate. I've waited until the safety valve it howling, but I'm nervous it'll blow up if I wait too long

Are you sure you are looking at the boiler safety valve or the anti vacuum valve which normally sputters until the machine gets to around one bar then snaps shut.

Yes, definitely the safety valve (just installed a new 3/8" auto-certified). Going to pull apart the pressurestat bladder once more tomorrow, then install a new pressurestat if not. Thanks for the help so far, everyone!