Rocket Evo v1 Sirai pressurestat removal

#1: Post by **CCS_56_EX** » September 25th, 2014, 9:35 pm

Over the last month, I've noticed the pressure has lost precision. It used to surf between .9-1.2. Lately, it's been between .9-1.5. I'm attempting to just remove the pressurestat, but can't get it to come off the bracket. Are there any tricks to do this? The bracket attaches to another fitting at the bottom of the boiler, but I'd have to take a lot of stuff apart to undo that. Looking at the pressurestat from the top, it looks pretty rusty and nasty in there.

#2: Post by **spiffdude** » September 25th, 2014, 9:40 pm

Just undo that silver nut under the bracket, it's what holds the pressurestat in place. I would disconnect the wires before, so you can lift it out of the bracket unhindered.

Here is a pic with the pressurestat out. For re-assembly, you drop the pressurestat in the bracket, then add the silver nut under the bracket, this effectively secure the stat in place. Lastly, you reattach your copper tube. Blow some air in that tube first, to return any lingering water in the spiral back into the boiler.

September 25th, 2014, 9:43 pm

Yeah, I can't get the silver nut to break loose, and there isn't a really good way to hold the pressurestat while trying to break it loose.

#4: Post by **spiffdude** » September 25th, 2014, 9:52 pm

That nut should not have been tightened that much... Anyway, got any plumbers pliers that has jaws you can space out so you could grab the bottom part of the stat, which is more of less squarish and might give you some leverage? Otherwise, grab the plastic body with your hand, might cause some damage though if you really manhandle it.

By the way, i was not really impressed with the durability of this unit. Mine was also rusted up and went south after only 3 years. I put in the big commercial Sirai, had to delete the water tank though... didn't mind as i am plumbed in.

Good luck

http://users.rcn.com/erics/ · #5: Post by **erics** » September 25th, 2014, 10:03 pm

This particular installation APPARENTLY uses just one set of contacts on a two set Sirai.

So, file any high spot on the set of contacts that is being used and swap the wires over to the unused set. You are then "good to go" for another X months.

#6: Post by **spiffdude** » September 25th, 2014, 10:12 pm

Yes Eric, it does use only one set of contacts.

But i think the OP is complaining about a widening deadband, which i would attribute to a stiffening membrane and not worn contacts? I may be wrong...

http://users.rcn.com/erics/ · #7: Post by **erics** » September 25th, 2014, 10:25 pm

I do not necessarily disagree but a deposition on one of the active contacts will result in the same.

As far as I'm concerned, these Sirai pstats have good points and bad and, while I'm at it, nothing approaches the reliability I have experienced with a simple MA-TER and accompanying SSR.

If need be, a 3/4" box end wrench or socket should grip the nut nicely. You should be(?) able to simply hold the pstat with your hands.

#8: Post by **spiffdude** » September 25th, 2014, 10:49 pm

So a deposit on an active contact may delay the circuit from opening up again, therefore increasing the top end of the pressure cycle? Interesting, didn't think about that.

Well OP, have at it and let us know how it goes.

You may want to try changing your wires to the unused pole as Eric suggests to see if the helps. I say this simply because if the inside (exposed to steam) parts are crusted up and/or corroded, there is not much to do unless you have replacement parts on hand. I tried to disassemble mine, clean it and reassemble but could never get it to seal properly again.

September 25th, 2014, 10:49 pm

I tried gripping it with my hand for about 15 minutes, and was really putting a lot of force into the wrench, but it wouldn't budge. I stopped because it just felt like I was going to break something. I'll give the plumbers pliers a go tomorrow.

http://users.rcn.com/erics/ · #10: Post by **erics** » September 25th, 2014, 11:16 pm

Looking down from the top of the pstat, you should be exerting a force on the wrench in a CLOCKWISE direction.