The retailer where I bought the machine (on-line) suggests that it might be a suspension valve issue. What is the suspension valve? Is it the same as the brew valve?

I wonder if they meant "infusion" valve...?
Details on all the parts of the E-61 group can be found here on my website:
How-To 19 - Overhauling and Lubricating the E-61 Group
But the infusion valve could be removed (missing) from the group and it would not cause the cool group temperature you are experiencing.

Maybe they meant the "expansion" valve? We might call it the pressure relief valve which regulates the brew pressure. If it is leaking it might cause this but I do not think so because it would also possibly cause low brew pressure and cooling of the group after it sits for a while even after coming to temperature.

Firstly, you should refer the on-line dealer from whom you purchased your machine to this thread.

Secondly, Bezzera has an excellent parts book for the Mitica Top which the dealer can quote the page & part number which he believes to be the problem.

Thirdly, when you do what I suggested, post some pics before and after. My testing methodology requires absolutely no flushing whatsoever . . . just 45 minutes of time.

My Quickmill Anita did this on two separate occasions. Both were caused by slight leaks in the fittings to the heat exchanger. The slight leaks would allow air (or steam vapor) to stall the thermal syphon action. The secret to the e61 is the convective flow that continuously heats the large lump of brass. For this to work, the brew water loop between the brewhead and heat exchanger has to stay sealed up tight and the group filled with water.

The hallmark of this is the nut at the top of the brew group cools down to where you can touch it. It should remain hot, as should the entire brew group should.

It could leak anywhere and cause the same issue. The Quickmill machines have HX fittings that sometimes leak. I don't know your machine. If you see a little white powder building up around a fittig - that's a leak. I never had the brew valves cause this, but I suppose they could.

erics wrote:Firstly, you should refer the on-line dealer from whom you purchased your machine to this thread.

Secondly, Bezzera has an excellent parts book for the Mitica Top which the dealer can quote the page & part number which he believes to be the problem.

Thirdly, when you do what I suggested, post some pics before and after. My testing methodology requires absolutely no flushing whatsoever . . . just 45 minutes of time.

Thanks Eric
I'll do that. When you say pics, what do you mean? Pics of the machine? What part?

What part?

The internals of the portafilter.

erics wrote: Thirdly, when you do what I suggested, post some pics before and after. My testing methodology requires absolutely no flushing whatsoever . . . just 45 minutes of time.

Here are the pics. before and 45mins later. No sign of water.

U2jewel wrote:What I did was this.

Machine cold, off.

Then lever to just beyond half way point. Leaving the lever there, turn on the machine.

Initially, for me, nothing happened. No water coming out from anywhere. Wait a bit more...
Then gradually, as your boiler comes up to temperature, you should hear the rumbling of water starting to boil.

Then the moment you see hot water coming out from the Grouphead/shower screen, move lever up to pump on position.

Let your hot water run for about 30 sec.

Pull down lever, stop the flushing.

No guarantee that this would work for you because a) I'm a dual boiler, you hx, so different architecture in plumbing.

Hello U2jewel,
I tried this. It actually seems to have worked. I'll keep you posted tomorrow when I turn the machine on.

Here are the pics. before and 45mins later. No sign of water.

I see what appears to be moisture in your first pic.

Tool chattering or rough casting marks?