Izzo Alex Single Boiler Low Grouphead Temp

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
Deluxe68

#1: Post by Deluxe68 »

This machine was made in 2009 and I have had it since new. Only water used was bottled AquaFina and there is no scale buildup that I have seen. When new the grouphead temperature gauge read 219F, during the first flush the temp would climb to 226 before decreasing. For the past 5 years the head temperature has dropped, now after warmup it reads around 215F and, if not used, the temp will usually drop even more down to about 200F. I just rebuilt the entire grouphead and replaced everything except the springs. I also replaced the boiler safety valve and vacuum breaker. I have tried loosening the mushroom nut but I cannot tell is air is escaping or the water is boiling on the surface. What else can I do?

JRising
Team HB

#2: Post by JRising »

Deluxe68 wrote: I have tried loosening the mushroom nut but I cannot tell is air is escaping or the water is boiling on the surface. What else can I do?
I think you're on the right track, looking for the very slow leak from the brew circuit that is interrupting the thermo-siphon effect that heats the head...
But probably not at the mushroom, check the brew valve (uppermost of the three in the head) to see if it might be leaking out the drain when the machine is idle.
Check the expansion valve to see if it may be leaking out your brew circuit water water.
Feel if the pump outlet feels very hot when idle, if so, your check valve is leaking brew circuit water backwards toward the pump.