Boiler Cleaning.

pete10uk

What’s the best way to clean out a Lelit Mara boiler.
We are in a soft water area so didn’t think scale would be an issue, however I removed the temperature probe today and it had a build up on it.

I can’t find any other posts on the forum but I’m sure it must have been asked before.

What do I need to do to clean the boiler?

I’m assuming strip it out and fill it with something and empty it without getting the contents in the rest of the machine?

Any advice on what to put in it and method gratefully received.

Thanks

Doram

pete10uk What’s the best way to clean out a Lelit Mara boiler.
We are in a soft water area so didn’t think scale would be an issue, however I removed the temperature probe today and it had a build up on it.

I can’t find any other posts on the forum but I’m sure it must have been asked before.

What do I need to do to clean the boiler?

I’m assuming strip it out and fill it with something and empty it without getting the contents in the rest of the machine?

Any advice on what to put in it and method gratefully received.

Not sure if this is still relevant, but Lelit Insider have a video on descaling the Mara X. With this method you will get the descaling solution to the tubes, group and steam wand as well, if you want that.

Puly make a descaler for coffee machines, and there are other products as well.

DavecUK

You’re half way there really. Get yourself a large syringe like @LMSC did and use it (with a bit of tube)to suck all the water out of the boiler through the temp probe hole. Then inject descaler solution, until it’s full.

Make up 1 litre of citric acid solution by adding 50g of citric acid powder to 1 litre of hot water.

Leave it over night, then suck all the descaler out….. Put the probe back, allow the boiler to autofill. Heat the boiler up, switch off machine, drain thru hot tap, Allow to refill and reheat, taste water, if it’s OK you’re done, if you can taste citric acid…repeat the rinse.

pete10uk

DavecUK thanks Dave.

What do I use to reseal the temperature probe? Ptfe tape presumably but not sure if you can use this on a hot tank or for food.

DavecUK

pete10uk What do I use to reseal the temperature probe? Ptfe tape presumably but not sure if you can use this on a hot tank or for food.

I always use PTFE tape, enough wraps so it’s tightish all the way in and don’t tighten it down fully….They use it on potable water fittings and it’s done me no harm. PTFE is relatively inert at the temperatures were talking about and you no doubt use a non-stick pan without any concerns

pete10uk

Thanks, makes complete sense.

100ml Syringe, Tubing and Citric Acid ordered, job will be done this weekend.

DavecUK

pete10uk 100ml Syringe

I was thinking more like 300ml…I mean 100 ml will get you there…but with a big boiler it might take a while. 🤣 I can’t remember if the mara boiler is 1.5 litre with a 11ml fill, or 2 litre with a 1.4l fill…I guess you will find out.

pete10uk

Just thinking of the storage afterwards.

I’m not loo bothered about having to do it 20-30 times.

blankets

Hi everyone (wondered why the old forum was a ghost town). My Bianca is probably due a descale now (₂ years old). I’ve only ever used Lockhills. Would you recommend descaling the boiler through the temp probe and then after a more general flush through the wands?

DavecUK

blankets Welcome to the forum.

blankets Would you recommend descaling the boiler through the temp probe and then after a more general flush through the wands?

As long as you are sure it’s scaled and very careful about the wires of the probe….ideally they should be disconnected on the push pull connector about 7 inches down the wires.. I personally don’t believe it’s necessary to remove the probe, unless it’s the brew boiler as unless they changed it the service boiler water exit is at the bottom. This boiler can simply be mostly drained by:

heating it up, switching off and opening the water wand, until nothing more comes out.
Then fill tank with descaler 50g Citric acid to 1 litre and then switch on to allow the service boiler to refill
Let it heat up, switch off, wait a few hours
repeat step 1 but this time with fresh water in the tank until you can’t taste descaler any more

For the brew boiler, always worth a quick look, in case they added a drain valve, as specifications are always subject to change. If not then yes, this can be done using a syringe, via the temp probe as described earlier. Just remember to refill the boiler, before switching the machine on…because there is no low water sensing in the brew boiler of most/;all dual boiler machines.

blankets

Thanks Dave. I’m confident of going in on the service boiler via the probe, but as you’ve said, it’s not necessary. The brew boiler looks much tricker (ref https://support.clivecoffee.com/en/lelit-bianca-brew-temp-sensor-replacement). Amateur questions:

To drain the brew boiler I’m assuming the machine should be laid down with the group head on the floor? Carefully remove the probe to expose the hole to get the syringe in? If I shine a torch in, I’ll gauge whether there’s any build-up.
If yes:
Do I then inject the acid/water solution in, til I think it’s full/ water appears inline with the probe hole (before it bleeds out).
Let it rest, then drain and repeat step two with just water, given you mentioned it doesn’t auto fill.

DavecUK

blankets Pretty much spot on, except the laying the brew group on the floor bit… just remove the top and shock the temp sensor off.

Evergreen88

Hi Dave, forgive my ignorance. Why can’t we descale the brew boiler simply adding the descaling solution to the tank and passing water through the grouphead engaging the pump?

I have an ECM Classika PID (single boiler) and was thinking to do that when the time comes.

DavecUK

Evergreen88 Hi Dave, forgive my ignorance. Why can’t we descale the brew boiler simply adding the descaling solution to the tank and passing water through the grouphead engaging the pump?

You can, but it’s hard to get the concentration up in the brew boiler…lots of start stops. The same difficulty is experienced trying to get all the descaler out.

pete10uk

Thanks for the reply.

It’s now been done, but useful information nonetheless.

I went down the citric acid route as suggested by @DavecUK. mixed 1L of water with 50g citric acid powder, got a 1m length of tube and 100ml syringe. only used the syringe to get a syphon going on both in and out, so it was very easy. Left the solution in for 6 hours and all looks perfect.

Only time will tell if it fixes my issue.

pete10uk The first symptom is I hear the boiler bubblin

blankets

Just as an update, I finally got some time to descale my 2 year old Bianca, used with Lockhills exclusively. Not the greatest photo, but you can see some scaling on the underside loop of the element, but not too severe(?).

After 4 hours it looked much better.

I followed this up with the official descale method using the purly solution mainly flushing the service boiler.

Looking at the scale built up over two years, any thoughts on whether it warrants a descale every year, or stick to two?

DavecUK

blankets It looked fairly clean, so I would only bother every couple of years.