Lelit PL62S-T Mara: Low Temperatures - Page 2

Need help with equipment usage or want to share your latest discovery?

Postby ironbrad » May 17, 2019, 3:35 pm

JRising wrote: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.

Thank you. I'll give this a try. Disappointed as I have not heard from the vendor I purchased this from and the machine is only 3 months old. I'm about done fiddling and prepared to donate the machine and move-on.

Thanks again...


Postby ironbrad » May 18, 2019, 4:39 pm

Well... Still no word from the vendor, but I've run just about everything over again, several times. I checked my Eric's thermometer in my pour-over kettle just at boil and it read 209 before my fingers got tenderized. Close enough for my quick test at sea level (70 ft) and 29.95 barometric pressure. The water stream from the Lelit hot water spout measured the same 208-210 (same short, hot finger test!) accompanied by some steam. Pressure is always 1 bar. The boiler temp and temp controller seem to be OK.

I rechecked for moisture in the PF basket: none. It appears I only see that after the screen has been wetted and it is the result of residual moisture condensing vs, GH/brew-valve leakage. I ran the suggested leak test (post above) and after 45 seconds under pressure, there were 2 or three drops each from the GH drain (open) and the shower screen - each. Given I had run some extended flushes checking for TS stall, and the fact that the PF basket was dry after a 90 minute warm-up this AM, I'm thinking this 3 month old machine is probably not leaking enough to cause the low GH temp. I checked with a thermocouple and my Fluke that correlated well to Erics thermometer, and it also shows a GH temp of about 170F after the machine idled 90 minutes this AM (no flushes except a real long one last night followed by a blind-filter backflush to assure no air in the system before shutdown.

I tore down the machine and checked everything I could top to bottom. No signs of any leakage, one wire up against hot copper I re-dressed, and three stripped sheet-metal screws is all there was to report.

At this point it seems my TS loop is simply and consistently not getting the GH near hot enough. It is not an air-stall if the techniques I mentioned are reliable. This leaves some sort of TS loop contamination or manufacturing defect resulting in poor circulation I would speculate. I should mention I only use bottled water with a measured TDS of 75. That and a nearly new, very lightly used machine should obviate scale I would think.

My back is completely shot and I'm seriously missing my morphine :shock: I've retired the Mara for my sanity and pain level and I'm now contemplating my next move.

Thanks to all in this thread and others that really helped me troubleshoot this. The one thing in this episode that is a keeper, HB!

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Postby slipchuck » May 18, 2019, 5:54 pm

Have you tried upping the pressure to 1.1-1.3 bar?


“There is nobody you can’t learn to like once you’ve heard their story.”


Postby Bluenoser » May 18, 2019, 6:37 pm

This is a big problem with designs of current espresso machines.. There is almost no way to tell if things are working properly unless you add more equipment to them. The S-T is little more difficult model to use because I think the PID is a fixed type without any method of adjustment. Thus you are limited to the fixed boiler/steam characteristics. I've read other owners of this model who have had issues getting the brew water hot enough; but their issues were somewhat due to the flushing routing. However, I think this can be a tricky machine to control brew water temp.

As long as your Eric's Therm. Is working correctly, the machine is obviously not working correct and one would hope that first line would pay for shipping back to them for repair. No normal user should have to do more than you have done to effect repair.

If you decide to write this one off and try again, the Breville DB has a good price point for its effectiveness and you might get better warranty service, depending on the vendor. (This can be bought at multiple places). But I'd be pretty upset to write off a 3 month espresso purchase.


Postby ironbrad » Yesterday, 5:02 am

slipchuck wrote:Have you tried upping the pressure to 1.1-1.3 bar?



It's almost 2AM and I've been up all night with my back. Working on that machine is murder! I should have checked when I was inside, but I never noticed the OPV and adjustment. Nevertheless, it is a good suggestion I should have tried but neglected. It's amazing how some pain can reduce your troubleshooting acuity :( I've already reassembled and moved the machine into temp. storage in the garage. Perhaps if I get a second wind and a better back-day I'll go back in and tweak the pressure up.

Thanks again all


Postby quantman » Yesterday, 1:41 pm

Sorry for your troubles with this machine.

I considered buying it as it looks like a very attractively priced HE machine and when I inquired about their return policy the sales agent advised me to read their Commercial terms (those are the terms this machine is sold under). Among the terms, there is a minimum 20% restocking fee (up to 50% if I recall correctly) for returns. Reading those terms I lost all desire to buy that machine.

But since you are in this situation and seeing as you might be done with it, it might be worth considering returning the machine in the hope of recouping 80% of it's value. (Edit: sorry, I just noticed that you have the machine about 3 months and the return policy is for 30 days so my suggestion is not relevant).

Another problem is that although these machines (from basically all vendors) are covered with some warranty performed by the dealer itself, I have seen nowhere in the terms any commitment as to how quickly your machine will be serviced. Then there is the cost of shipping the machine at the customer's expense. I feel like these policies are very effective at shifting the purchase risk to the customer.

One of the reasons I ended up getting a Breville DB from BB&B was the 90 day no questions return policy and the well documented history reported in this forum of positive warranty performance. The new machine even comes with a pre-paid shipping label! The BDB is a real pleasure to use.


Postby ironbrad » replying to quantman » Today, 8:18 am

Thanks for the thoughtful input Quantman (are you a stock-market quant?). I always buy stuff like this assuming it rests on my shoulders if something goes wrong. I've written this off as a learning experience and have a new machine on its way from WLL. I'll eventually diagnose what was wrong with the Lelit and learn a lot in the process. HB is a great source for all kinds of information and I've enjoyed the fine support I've found here.

Live and Learn :D