Bounder: Vacuflush Follow Up

[Elwood58]

We did the bellows and duck bill refresh at the five year mark. We did the work in the middle of the pandemic, so not much use of the system since. I have been doing other projects on the motor home and check the Vacuflush when there.

Holds vacuum for weeks
Cycles in 25 seconds at 1000 feet above sea level

The only real problems we have ever had were self induced. Too much TP by grandkids and a piece of plastic wound up in toilet and jammed in duckbill exit once.

We did add dynamat sound deadening material wherever we could in the Vacuflush area.

[computerguy]

Wish I could figure out why mine is losing vacuum in only 5-10 hours. It is variable. I am thinking the one connection to the vacuum tank with the rubber fitting might be it.
It is taking 2 minutes at 7000 ft elevation for the past few weeks

[RRR]

Originally Posted by computerguy

Wish I could figure out why mine is losing vacuum in only 5-10 hours. It is variable. I am thinking the one connection to the vacuum tank with the rubber fitting might be it.
It is taking 2 minutes at 7000 ft elevation for the past few weeks

Put shaving cream around the joints. If there is a leak it will draw it in.

[computerguy]

Originally Posted by RRR

Put shaving cream around the joints. If there is a leak it will draw it in.

I think as slow as the leak may be the shaving cream would dry up before a leak could be detected.
This one I may seek a professional. Marinesan sent me a list of authorized service centers

[16bounder]

Just thinking, how long have you been at such elevation? I am guessing that POSSIBLY the difference in atmospheric pressure just might come into play with the effectiveness of the vacuum pump. If not permanently situated there I'd wait (if not too inconvenient) till you return to lower elevation......fingers crossed.!!!!!

[computerguy]

Just to follow up.
The last week or so it was not shutting off.
I was getting plenty of vacuum to evacuate the toilet it just would not shut off.
That sort of confirmed my belief I did have a leak or much of a leak.
I checked all the connections one last time. This time opening the vacuum pressure switch to view. I simply touched it and the motor shut off.
A call to Dometic Sanitation brought new light onto the subject.
These vacuflush systems were not designed for altitude use. Originally there were for boats mainly at sea level. Then introduced to rvs later.
Altitude then came into play. At higher altitudes generating vacuum is more difficult.
There is a different vacuum switch available for those who use it between 4-5000 ft above sea level. The high alt switch has a lower threshold of vacuum to generate so it will shut off. Above that and higher vacuum can be guaranteed. If above 5000 feet best to shut it off after 1 minute of running. Then before flushing let run for a minute to let vacuum create.
I’m at over 7000 feet elevation outside Yellowstone NP. All’s good with me now

[RRR]

Interesting. We we at West Yellowstone last year with 3 grands and while it ran a little longer never had a problem.

Wonder it Dometic told the brain trust at Fleetwood they might not work at elevation?

[computerguy]

Originally Posted by RRR

Interesting. We we at West Yellowstone last year with 3 grands and while it ran a little longer never had a problem.

Wonder it Dometic told the brain trust at Fleetwood they might not work at elevation?

I spent a month in Moran WY and now another month on the west side of Yellowstone. Amazing! My favorite NPs without question.

I am sure FW knows about the high altitude thing. Or should I say one or two people know about it. Sure would be nice if it was documented and owners told about it. But I guess they tell you to read all the manuals for each component in the rv. That's their out.
I'm just glad mine is not a "problem" and working as designed for my altitude. Should return to normal below 4000 feet. I simply can power it off after 30-60 seconds.
I have a major gag reflex and have ZERO enjoyment taking the pump apart.