Trying to dial in consistency, so I added Eric's thermometer. After 75 minute warmup, reading sits at 176F (ambient 70F) portafilter attached. 10-20sec flushing brings it up to about 194F then it steadily falls if flush continues. The same behavior is seen during a ~25sec shot. Idle temp quickly returns to about 176-178F.

These temps seem low and my espresso beverage temps are cooler than my Technivorm Moccamaster drip. I've left a message on the 1st-Line support page, but I was wondering if there are any thoughts/suggestions among the experienced folks here?

Thanks,
Brad

Edited: PL62S-T machine

After it has idled for a half hour or so, raise the control lever with no portafilter in place... Do you immediately get a rush of steam followed by water after a few seconds, like you'd expect? Or, do you just get weak steam like the Heat Exchanger has been leaking out water? Do you immediately just get a rush of water, like it's not above boiling temp despite being in an idling Heat Exchanger?

No rush of anything, just the normal water distribution through the screen (just like when I rinse the screen post-shot). Temp sits at 178F +/- . Definitely not above boiling!

Thanks for the help

I've read (here?) that there is a manually adjustable PID controller inside the machine? Yes/no? Does anyone have any information regarding it?

It sounds to me like your boiler is not nearly hot enough. If your Heat Exchanger hasn't warmed up to boiling temperature after a half hour of idling, it's possibly leaking off the steam and sitting half empty, or the boiler isn't hot enough to heat it up. What's does the boiler gauge say the pressure is? If you let out a bit of hot water is is steaming ferociously as it escapes the aerator? Is the steam volume sufficient to bring a cup of water up to painfully hot? Which Mara do you have, the PL62S or the PL62T or is there seriously a PL62S-T that I've never heard of and Lelit doesn't promote on espresso.lelit.com ?

Is the S-T the one with the fixed PID?.. On my PID version, no flash steam ever happens from the group.. this is a characteristic of newer designs with a thermosiphon restrictor and a PID.

However, those temps are much too low. You may have an air-locked thermosiphon. Look at some posts that will help to unlock the air.. One solution is to do a long discharge.. Air can get in the thermosiphon if you do a lot of micro-flushes to clean the screen.. (less than 1 second).

Look for water underneath to see if you have a leak somewhere..

When you lock a dry portafilter in and leave it for 10 minutes, do you notice any water vapour in it (it should be dry)

JRising wrote:It sounds to me like your boiler is not nearly hot enough. If your Heat Exchanger hasn't warmed up to boiling temperature after a half hour of idling, it's possibly leaking off the steam and sitting half empty, or the boiler isn't hot enough to heat it up. What's does the boiler gauge say the pressure is? If you let out a bit of hot water is is steaming ferociously as it escapes the aerator? Is the steam volume sufficient to bring a cup of water up to painfully hot? Which Mara do you have, the PL62S or the PL62T or is there seriously a PL62S-T that I've never heard of and Lelit doesn't promote on espresso.lelit.com ?

Boiler gauge sits at 1 bar. Releasing hot water there is no ferocious steam there as I recall (don't use it much), but I'll check again. Steam brings my 125mL of milk to too hot to hold very quickly every morning for my cappuccino. There is indeed an unadvertised (at Lelit) S-T version of fixed PID sold by 1st Line occasionally.

Bluenoser wrote:Is the S-T the one with the fixed PID?.. On my PID version, no flash steam ever happens from the group.. this is a characteristic of newer designs with a thermosiphon restrictor and a PID.

However, those temps are much too low. You may have an air-locked thermosiphon. Look at some posts that will help to unlock the air.. One solution is to do a long discharge.. Air can get in the thermosiphon if you do a lot of micro-flushes to clean the screen.. (less than 1 second).

Look for water underneath to see if you have a leak somewhere..

When you lock a dry portafilter in and leave it for 10 minutes, do you notice any water vapour in it (it should be dry)

Yes, S-T is the fixed PID. I'll research the air-locked thermosiphon. No water anywhere leaking. The dry portafilter DOES get water vapor in it when I loosely lock it into the head; what does that indicate?

Thank you all.

Turned my machine back on and after 50 minutes of warmup:

1. The portafilter, which was left attached, was dry this time.

2. The water spigot released gurgling, steaming hot water.

3. The grouphead thermometer showed 177F.

4. Steam gauge sat at 1 bar.

No flushes used.

ironbrad wrote:Trying to dial in consistency, so I added Eric's thermometer. After 75 minute warmup, reading sits at 176F (ambient 70F) portafilter attached. 10-20sec flushing brings it up to about 194F then it steadily falls if flush continues. The same behavior is seen during a ~25sec shot. Idle temp quickly returns to about 176-178F.

These temps seem low and my espresso beverage temps are cooler than my Technivorm Moccamaster drip. I've left a message on the 1st-Line support page, but I was wondering if there are any thoughts/suggestions among the experienced folks here?

Hi Brad. It sounds like you have the PL62S (non-pid) version. I had a similar issue with a low group idle temp and the folks here on HB were glad to help. You can review the thread on the link below. There is some good Mara specific information within the thread that I obtained and shared. Eric Svendson has shared this document in the past detailing boiler pressure and temperature correlation, relative to your elevation. This could be helpful in checking the expected boiler temp, since you don't have a PID readout. It looks like you are pretty much at seal level so you boiler temp should be about 247*F according to the graph and your stated boiler pressure of 1 bar. In the end, I found my brew valve was leaking ever so slightly. I only experienced low group temps intermittently but it has been solid since installing the new valve seal. Sounds like you have both low group and water temp in general.

You could maybe pull the lid and check the temp of the top of the boiler if you have access to a contact or non-contact measuring device (it will read a bit lower than internal). It would also allow to check for any steam leakage externally or though the drain back to the water tank. On the thread below there is lots of guidance for the checks you can make. Good Luck

Lelit Mara - Thermosyphon restrictor and stalled..

ironbrad wrote: Yes, S-T is the fixed PID. I'll research the air-locked thermosiphon. No water anywhere leaking. The dry portafilter DOES get water vapor in it when I loosely lock it into the head; what does that indicate?

Well thank you for introducing the S-T to me... I am intrigued...

And I am now thinking that your brew valve (The upper valve in the E-61 Head) has a slight leak. It allows the steam to escape from the HX through the brew head. The small steam leak isn't enough to appear as water drops falling from the head, but does condense as droplets in the portafilter as suggested by Bluenoser.
Try this: With the portafilter away from the machine and the lever down, the brew valve should be closed and the other two valves should be open. Press and hold the button behind the control lever without raising the lever, to run the pump with the brew valve closed. This may be hot, you may want to put on a rubber glove or something. If water begins dripping from the group head, then you're proving that the brew valve leaks. You can get the valve out by removing the mushroom section on top of hte brew head. You can replace the complete brew valve, or just the rubber. If it is "BAD" bad, consider re-facing or replacing all three valves.