zwap wrote:I guess I could have made it shorter, and perhaps only used 2 o-rings, but I don't have an issue with space, as I have already removed the reservoir and will be plumbing the water supply as soon as the 1/4" braided hose, filter, and pressure-limiting valve arrive. It's just a slip fitting so that if I want to remove the drip tray, I can quickly disconnect the drain hose. I just copied the LM design.

Hi Gavin - I'm looking into pressure regulator for the Linea Mini as well. Do you mind sharing which one you got? Thanks!

I'll post pictures when it arrives. A friend ordered it for me but I have no idea what brand etc. Its the one he recommended and uses on his machines.

Thanks! I'm particular interested in the pressure vs flow rate chart of the regulator, as LM asks for 45 psi dynamic pressure, and this will results in a higher static pressure.

I got the mini all plumbed in today. It's so nice not having to fill the reservoir or empty the drip tray.
Unfortunately, the pump is noticeably noisier than it was when it was drawing water from the tank. Is this normal for rotary vane pumps when you go from water at atmospheric pressure, to water at a higher pressure? If anybody has experienced something similar, I'd be keen to hear.

I checked all the specs in the installation guide here: http://home.lamarzoccousa.com/wp-conten ... eamini.pdf

My dynamic pressure is sitting at 45psi.
I'm using a 3/8" feed hose. I took the 3/8" to 1/4" adapter out of the pump port and put a 3/8" elbow in instead.
I was disappointed to see that the filter that arrived only flows 0.5GPM and the manual says it requires 2GPM. I figured that this must be my problem and the noise might be from pump starvation, so I removed the whole filter assembly and just piped the water from the mains, through the pressure limiting valve, and into the pump. This made no difference, so clearly the low flow rate through the filter is not the problem.

I'm at a loss to explain it. Maybe cavitation caused by the elbow going into the pump?

Anyway, here are some pics of the various bits:

I posted some pics the other day of the brass fittings I made for the drip tray. Here they are installed.


I wish I had remembered to take pics of this before I put the cover back on, but this is the elbow in the pump port, and the 90 degree fitting on the hose.


It runs down under the pump and through the hole next to the water level sensor. I put a rubber grommet in to protect the hose.


For the water level sensor, I just disconnected the little crimp tags from the screws on the back of the plastic plate, and connected them together by screwing them together under the same nut on one screw. This means that the controller thinks the tank is always full.

Under the bench, I have an Omnipure Q5486 scale reduction carbon filter and an OR SABO pressure reducing valve. I'm going to replace the filter with one that can flow at least 2GPM, so that I'm within LM specs. The filter housing has 3/8" BSP ports both sides, so I have a 1/2" x 3/8" nipple on the mains side to connect to the water tap. On the valve side, I just have a straight 3/8" nipple. The valve has 3/8" ports as well. There's a 3/8" hose that runs from the valve to the pump. I added a 0-1000kpa pressure gauge to the bottom of the valve, for convenience when adjusting the line pressure.


I'll upload a picture of the flow/pressure curve for the pressure reducing valve. At the recommended 45PSI, it flows about 10GPM according to the chart.

Today I removed the brass elbow I had fitted to the pump and replaced it with a 3/8" BSPP stainless fitting with a dowty washer. This is closer to how the factory had fitted the 3/8" x 1/4" adapter. I read some fluid-o-tech documentation which said not to use elbows or sudden changes in diameter close to the pump, to reduce the chances of cavitation.

Anyway, after fitting it all back up, no change in the noise level, so I set it back up using the internal tank and the noise was just the same. So I've decided that the increased pump noise was all in my head. I even took the pump off and ran the motor and it sounded exactly the same. The noise that was bothering me is just the sound of the motor running.

Anyway, it's all back together now, and I'm happy again. Here are the pics of the inside that I forgot to take last time the cover was off.

zwap wrote:Today I removed the brass elbow I had fitted to the pump and replaced it with a 3/8" BSPP stainless fitting with a dowty washer. This is closer to how the factory had fitted the 3/8" x 1/4" adapter. I read some fluid-o-tech documentation which said not to use elbows or sudden changes in diameter close to the pump, to reduce the chances of cavitation.

Anyway, after fitting it all back up, no change in the noise level, so I set it back up using the internal tank and the noise was just the same. So I've decided that the increased pump noise was all in my head. I even took the pump off and ran the motor and it sounded exactly the same. The noise that was bothering me is just the sound of the motor running.

Anyway, it's all back together now, and I'm happy again. Here are the pics of the inside that I forgot to take last time the cover was off.

<image>

When I read your post this morning I was going to ask if you'd put it back to tank and compared pump sound. Which you've since done without my asking. Good to hear all is well, except for maybe mind game Gremlins.

I was going to say I noticed no pump noise difference between plumbed and reservoir. I did make sure my filter was sized for decent flow, though I can't imagine the need is all that great. For data purposes, I'm in a city at roughly 35psi static, never bothered making a pitot tube.

Note, I do hear a minor steam noise now that I didn't hear before. very faint. I think I might have loosened something while reconnecting everything, and am going to check on it with leak detector eventually.