Help please, boiler temperature wont go above 190. Even with the pstat wide open and relief valve getting a real workout. My machine is identical to the isomac millenium with a e61 group...it is a euro2000 junior. I am showing 1.5 bar pressure. could it be that i need aggressive descaling

Thanks Sunny.

or maybe i need a new relief valve. At what pressure is the relief valve supposed to open?

sunnyu wrote:Help please, boiler temperature wont go above 190. Even with the pstat wide open and relief valve getting a real workout. My machine is identical to the isomac millenium with a e61 group...it is a euro2000 junior. I am showing 1.5 bar pressure. could it be that i need aggressive descaling

Thanks Sunny.

Something doesn't add up; 1.5 bar pressure on a front panel gauge is a helluva lot hotter than 190 degrees F, unless you are talking about degrees C, and why on earth someone would want a temperature above 190C in their espresso machine boiler is beyond me.

Either the FPG is giving an incorrect reading or your boiler temp is above 190F; I'd guess a FPG reading of 1.5 bar should equate to a boiler temperature of at least 250F. Even if your e-61 thermosyphon wasn't working I can't see how the water could cool down that much (to below 190F) at the group head unless you only tried to make one shot from idle.

So, again, this is impossible to evaluate without more information. Where, and how, for example, is the 190 degrees being measured? Does the FPG behave normally, e.g. does it go down to zero when the machine is turned off and then rise to 1.5bar, or is it stuck in position?

ken

Ken thanks for responding. I can repay the favor by sharing how to repair a CEME pstat should you ever need to do so.

The pressure gauge is working fine because the relief valve is constantly releasing at 1.6 bar. The temperature is the suspect, at 1.5 I am getting 190F, and i can tell because the shot is underbrewed. Under what circumstance could 1.5 bar only equate to 190f.....dirty tank?

I am measuring the temp at the hot water outlet. Through the group head its 10f lower. I believe that somehow the tank is developing more pressure than heat. Is it possible?

sunnyu wrote:I am measuring the temp at the hot water outlet. Through the group head its 10f lower. I believe that somehow the tank is developing more pressure than heat. Is it possible?

If your vacuum breaker is not working properly (these things fail) then you could have "false pressure" in your boiler. You can test for this by letting off steam from the steam wand. If you get air the first time and little steam that could explain it and then the FPG reading should be more correct or correct once heat builds back up and the boiler fills with steam rather than hot air. If this is the case you will need to bleed off the hot air each time the machine heats up from being cold.

Replacing the vacuum breaker or *possibly* cleaning it up and replacing the O-ring will return the valve to functionality and the problem won't recur until you have gone through your next Vacuum breaker or O-ring.

ken
p.s vacuum breaker is the thing that should hiss, under the cup tray generally, when your machine heats up. It should be readily accessible somewhere near the top of the boiler.

The vacuum valve is fine, whats more my temp stays at a consistent 190 shot after shot. i even bypassed the safety thermostat in case it was sending a false signal. But your slant made me think, could too much or too little water in the tank case similar symptoms to air lock. i.e. getting too much pressure without the corresponding heat.

sunnyu wrote:I am measuring the temp at the hot water outlet. Through the group head its 10f lower. I believe that somehow the tank is developing more pressure than heat. Is it possible?

Measuring the temperature at the hot water tap is not very useful information. As Ken suggests, determine if your boiler pressure gauge is indeed reflecting reality (if the safety pressure relief valve is opening, that would suggest the reading is correct). If all your shots are sour, the extraction times are reasonable, and you see no blatant channeling, I would suspect that your initial hunch about the HX being scaled is correct. The thread Sputtering e61 & HX scale build-up - Cured! describes this same problem, including this picture:


Part #21 from the E61 patent diagram, AKA "the mushroom"

sunnyu wrote:...could too much or too little water in the tank case similar symptoms to air lock. i.e. getting too much pressure without the corresponding heat.

It's possible that the water level could be so low that the HX was rendered ineffective, but I would first suspect (a) overflushing or (b) scale buildup. A boiler pressure setting of 1.5 bar is considered blazing hot, giving more weight to (b).

sunnyu wrote:The vaccum valve is fine, whats more my temp stays at a consistent 190 shot after shot. i even bypassed the sfatey thermostat in case it was sending a false signal. But your slant made me think, could too much or too little water in the tank case similar symptoms to air lock. i.e. getting too much pressure without the corresponding heat.

I think it is pretty simple; if in fact you are measuring boiler water temperature, and there is no vapor/air lock in the boiler (e.g. "false pressure"), a boiler pressure of 1.5 bar or above does not equate to 190F. Therefore, either your measurement technique or the front panel gauge are wrong. As a result, you either have an error in your measurement technique or your front panel gauge is giving you erroneous information. The fact that the safety thermostat triggers just above the 1.5 bar setting (if I got that part right) would indicate to me that you would need BOTH the safety thermostat AND the FPG to be malfunctioning in order to explain the problem in any other way than that you are not getting an accurate measurement of boiler temperature.

So, I think your measurement technique is flawed. By the time that water comes out of the water wand or the steam tip, it is going to be at no more than the local boiling point or it will not be liquid, it will be a gas. Water boils at 212F at sea level and less than that at elevation. Therefore, the only way to measure a boiler temperature in excess of 212F at sea level would be under pressure, such as with a thermocouple INSIDE the boiler.

Venturing a wild guess I would say that your measuring technique is faulty or you are losing at least 22F (if you are at sea level) between the boiler and the wand exit. You may also have a faulty measuring device. The problems with your espresso taste may have nothing to do with any of this.

Sorry, but I have run out of ideas except those above.

ken

Dan thanks for your logic, i feel certain that you have nailed it. Scale is insulating the HX!

And yes i was improperly measuring the temp at the wand, which is unrelated to me getting lukewarm shots.

Thanks guys