Flush Guard Vacuum Switch

[alnav]

I'm in need of a replacement for a failed Vacuflush vacuum switch and happened on this while shopping: https://theflushguard.com

Claims to monitor the vacuum and shut off the pump if a leak is detected. If it does, simple power recycle will enable the next flush. Direct (and seemingly easy) replacement for both kinds of Dometic systems. Price is about the same or even less than the Dometic part.
Has anyone tried this?

 

[GnrlPatton]

Interesting. I've got a vacuum switch on order right now since mine has also failed. I have had a few times where the pump continued to run, so I've made it a habit to shut off the system between flushes. This looks like a good solution for that problem.

 

[SportDeck]

I have two. They are a must have. Your system will leak, and the pump will run, and eventually the pump or your battery will die. This prevents it, has no moving part (its electronic), requires no re-wiring, and installs in 15 minutes. I love my vacuum flush system now, as it operates with so little water that I can go through the Michigan summer with one pump out, but without the Flush Guard, it is a constant worry about the pump running. This is even more of a problem for an unknown leak, as you might think you fixed it, only to have the pump end up burning out because you had not fixed it.

It seems the seal at the bowl work can't seal unless there is water in the bowl. When you have a leak at the bowl, the water gets sucked out, and then the pump can't make it seal again. Usually just flushing fixes it, so this this thing just inhibits the pump from running until it get reset by cycling the power.

For my guest head, I replaced my pull-on/off toilet power switch switch with a momentary switch that is normally closed. When I have guests onboard, I tell them to press the button before using the toilet. 99% of the time it does nothing, but if the pump was disabled, it re-enables it. Before the Flush Guard I dreaded the thought of waking up my guests at 3 am to tell them to flush again because the pump was running.

 

[Skybolt]

@alnav Al that looks pretty nice, I especially like the optional button with status light (Momentary? w/light).

I don't like the way the tube is connected to a small zerk like fitting. Possibly put sealer around the tube and fitting?
also Tygon won't last long in that situation, under vacuum most of it's life. I am thinking couple three years then trouble again. Could be wrong but doesn't look like years of use like the OEM is/was.

 

[alnav]

@alnav Al that looks pretty nice, I especially like the optional button with status light (Momentary? w/light).

I don't like the way the tube is connected to a small zerk like fitting. Possibly put sealer around the tube and fitting?
also Tygon won't last long in that situation, under vacuum most of it's life. I am thinking couple three years then trouble again. Could be wrong but doesn't look like years of use like the OEM is/was.

Orlando, astute observation; the instructions do call for sealing the tube and fitting.
I didn't end up installing. The problem was my boat (and I assume lots of others) has an additional wiring arrangement added by Sea Ray to provide the status lights in the heads so there are 4 wires coming in to the vacuum switch. A marina tech and I couldn't figure out how to get the switch to work properly with the two wires provided and we couldn't get a manufacturer rep on the phone before we ran out of time (I needed to finish winterizing before going overseas). I did speak to the product lead (nice and dedicated guy) the next day and he promised to spend some time on a Sea Ray over the winter to develop a solution for this set-up. So, hoping to install in the spring.

 

[Skybolt]

Orlando, astute observation; the instructions do call for sealing the tube and fitting.
I didn't end up installing. The problem was my boat (and I assume lots of others) has an additional wiring arrangement added by Sea Ray to provide the status lights in the heads so there are 4 wires coming in to the vacuum switch. A marina tech and I couldn't figure out how to get the switch to work properly with the two wires provided and we couldn't get a manufacturer rep on the phone before we ran out of time (I needed to finish winterizing before going overseas). I did speak to the product lead (nice and dedicated guy) the next day and he promised to spend some time on a Sea Ray over the winter to develop a solution for this set-up. So, hoping to install in the spring.

Funny they don't list compatibility with the original VG unit, but that is the only one that has two wires. Good timing on this as I am about to rebuild my VG12VDC unit and was going to replace the v-switch. Still not sure about the tygon tubing, but I really like what they offer in the status department (blinking switch).

Good luck on the install. Please post back on what they came up with.

 

[SportDeck]

Funny they don't list compatibility with the original VG unit, but that is the only one that has two wires. Good timing on this as I am about to rebuild my VG12VDC unit and was going to replace the v-switch. Still not sure about the tygon tubing, but I really like what they offer in the status department (blinking switch).

Good luck on the install. Please post back on what they came up with.

I was curious about the 4 wires, and found a description of this. Apparently the "Full" float sensor disables the vacuum pump. From the diagrams I saw, the only wiring change you would make would be to remove the two red wires that are currently connected to the existing vacuum switch, and connect these to the switch connection on the Flush Guard. No wiring would be altered. Which red wire goes to which terminal on the Flush Guard makes a difference, but it is easy to tell if you get it backward because the pump runs the instant power is turned on, and won't stop. When you reverse the connections so it is correct, there is a 10 second delay in the pump running the first time it turns on, and of course it stops the pump after the vacuum is reached, or 3 minutes elapses (meaning it detected a leak).

 

[SportDeck]

I was curious about the 4 wires, and found a description of this. Apparently the "Full" float sensor disables the vacuum pump. From the diagrams I saw, the only wiring change you would make would be to remove the two red wires that are currently connected to the existing vacuum switch, and connect these to the switch connection on the Flush Guard. No wiring would be altered. Which red wire goes to which terminal on the Flush Guard makes a difference, but it is easy to tell if you get it backward because the pump runs the instant power is turned on, and won't stop. When you reverse the connections so it is correct, there is a 10 second delay in the pump running the first time it turns on, and of course it stops the pump after the vacuum is reached, or 3 minutes elapses (meaning it detected a leak).

Opps. My comment about the two red wires might not always be correct! I see they updated the manual at theflushguard.com and it now shows how to wire it up when you have more than 2 wires going to the vacuum switch, and it even mentions sea ray.

 

[alnav]

Opps. My comment about the two red wires might not always be correct! I see they updated the manual at theflushguard.com and it now shows how to wire it up when you have more than 2 wires going to the vacuum switch, and it even mentions sea ray.

Sounds like the guy I talked with followed through. Glad to see it as it seems to be rare these days.