Is it possible to get rid of the pressurestat on my Elektra T1?

Need help with equipment usage or want to share your latest discovery?
cruzmisl
Posts: 167
Joined: 16 years ago

#1: Post by cruzmisl »

Hi All,
I'm thinking I'm getting tired of the constant clicking sound of my pressurestat. I was curious if there is a PID kit for the T1 that is relatively easy to install or are they still a DIY project?
Thanks,
Joe

User avatar
cannonfodder
Team HB
Posts: 10507
Joined: 19 years ago

#2: Post by cannonfodder »

Anything is possible. I have not seen a PID kit made for an Elektra. You would have to get a PID, SSR, thermocouple and home brew it. After 5 years, I dont even hear the click.
Dave Stephens

Advertisement
User avatar
shadowfax
Posts: 3545
Joined: 19 years ago

#3: Post by shadowfax »

I did it, and you can read about it here. As Dave said, you have to cut your own path here. There's a link to the boiler fitting you will need in the thread I linked to.

If you hate the noise but don't want to spend a huge amount of money, get a different pressurestat and a SSR. As per Paul Pratt's discussion of pressurestats, A CEME or MATER stat is quieter, smaller, cheaper, and will probably last a pretty good amount of time if you properly isolate it from switching the element using an SSR. Please note it's absolutely essential to use a 20A+ relay of some kind for any other pressurestat than the Sirai; they won't appreciate the current the Elektra's heating element draws.
Nicholas Lundgaard

User avatar
cannonfodder
Team HB
Posts: 10507
Joined: 19 years ago

#4: Post by cannonfodder »

CEME or MATER stat is quieter, smaller, cheaper, and will probably last a pretty good amount of time if you properly isolate it from switching the element using an SSR. Please note it's absolutely essential to use a 20A+ relay of some kind for any other pressurestat than the Sirai; they won't appreciate the current the Elektra's heating element draws.
You can hook them up without a SSR, and they will work, once.
Dave Stephens

cruzmisl (original poster)
Posts: 167
Joined: 16 years ago

#5: Post by cruzmisl (original poster) »

OK that's good intel. I can always count on the members of HB to help me out.

Its strange but after 3 years I started noticing the clicking more. Part of that may be due to the new hardwood floors recently installed that replaced carpet. The wood absorbs no sound and it echoes more than it used to.
Is it possible for the pstat to get louder with age?

I'll take a look at the links provided. Any other thoughts appreciated.

stevescapin
Posts: 79
Joined: 17 years ago

#6: Post by stevescapin »

I replaced the pressurestat by a PID on my two group Elektra and it works like a charm. I read (and re-read!) Shadowfax's threads, which proved invaluable to restore my Elektra. He was gracious enough to provide some advice when I contacted him about the PID transformation. I am by no means an mechanical and electrical expert, yet I found the transformation fairly straightforward once you have all the required parts. PM me if you need info about parts...

User avatar
shadowfax
Posts: 3545
Joined: 19 years ago

#7: Post by shadowfax »

Just for what it's worth on the whole "PIDing an Elektra" thing: It's mostly a total waste of time unless you're just really interested in getting hands-on experience with PIDing a machine. I was, and it was great fun for me. In terms of practical benefits, on an Elektra I'd say you'll get 100% of the benefit by switching to a pressurestat that has an 0.1 bar deadband. The control of the boiler temperature is very, very far removed from the temperature you get at the grouphead. As you can see in my Elektra restore thread, I also used a second PID as a thermometer-only and hooked it up to a small-gauge thermocouple snaked in behind the shower screen on my machine. That's considerably more useful information, and definitely gives a little extra feedback at how good I am at flushing. Still, it's unnecessary on the Elektra, which is pretty consistent if you just count of the same amount from when the sputtering stops during a cooling flush.

This Mater Pressurestat is the current pressurestat in use on La Marzoccos that don't have a PID-controlled steam boiler. They switched over from using Sirai stats, so that should be the right diameter on the connection in the T1. You'll need a SSR with 120VAC control, rated for switching 120VAC (or higher) and 20A (or higher). This is an example of one such relay for ~$30. A heatsink like this would also be a good idea. Get yourself some white and black 12 gauge wire and you're ready to go-the hardest part will be mounting the SSR inside your machine.
Nicholas Lundgaard

Advertisement
cruzmisl (original poster)
Posts: 167
Joined: 16 years ago

#8: Post by cruzmisl (original poster) »

Shadow, I like that idea better. Less than a hundred bucks and relatively little work. Is the wiring fairly straightforward? Why do I need the relay anyway? The T1 draw too much juice?

User avatar
shadowfax
Posts: 3545
Joined: 19 years ago

#9: Post by shadowfax replying to cruzmisl »

The wiring is easy if you're familiar with wiring relays. I'll take a stab at a full explanation from memory of how the Elektra is set up: You will need to run new, separate wire from the hot and neutral terminals on the on-off switch of the machine-from the side that will get power cut when the machine is off. You would run the hot wire out to the new pressurestat, on the topmost terminal there. Then you would run a line from the normally closed (NC) terminal on the stat to one of the terminals on the input side of the SSR. Finally, hook the neutral wire coming from the on-off switch to the other input terminal on the SSR.

For the line side, it will look similar to the way it is on the Sirai, with one major difference: where the Sirai switches both the hot and neutral wires going to the heater, you're only going to switch one of the legs (conventionally, this should be the hot one). So, you will pull the neutral wire that goes from the switch to the Sirai and hook this straight to the heating element. Then you'll take the 2 lines from the hot side that originally went into the Sirai and hook those to opposite terminals on the load side of the SSR. You should have one wire left over, the neutral wire that originally went from the heater to the Sirai pressure stat. Simple, right? I'll leave this up for grabs to any electrical engineers that want to nitpick on a more proper way to do it.

You'll need to find the right connectors to attach to the various spades you're going to have to attach to, and a soldering gun and set of heat-shrink tubing will also come in handy if you want to do good work. If terminating wires properly is something you don't know how to do, that ought to be a deal breaker on this-doing crappy work on a ~$3000 espresso machine will devalue it shamefully and also put it at risk.

Anyway, as for why you need a relay, the answer is because they're more reliable and also rated for the current that the Elektra's element draws, which IIRC is 18-19A. The internal relay on the MATER pressurestat is 16A, and I wouldn't hook it straight up to a heater even if it was within that generous rating.
Nicholas Lundgaard

User avatar
cannonfodder
Team HB
Posts: 10507
Joined: 19 years ago

#10: Post by cannonfodder »

Now and then I get the bug to modify my A3. I have had it for years now. I have toyed around with the idea of adding a group thermocouple to get the shower screen water temp kind of like the home made E61 adapter I made years ago. Then I get on eBay and look up parts and prices. I inevitable end up grabbing my Scace and Fluke, let it all heat for a half hour then think to myself, OK, I want to hit a 199.5 brew temperature. Stand there and flush the group, count in my head, lock in the Scace and pull my shot. 199.3 to 199.7 at the end of the shot. Hmm, guess I really don't need it. So I buy more coffee. Thought about adding a shot timer and preinfusion delay on make relay to the pump as well. Then I pull a shot, dang yummy, so why mess with it. So I buy more coffee. To date the only modification I have made to it is insulating the boiler which was something I did right after I got it.
Dave Stephens

Post Reply