Dune
Senior Member
First off this is a head that is rarely used, so I was pretty surprised when I hit the flush foot pedal the other day and no vacuum and no pump sounds coming from the engine room (where all four vacuum pumps are).
1. Nothing wrong with pump itself. I know this as I switched wiring from one pump to another one and flushed it's head and the pump worked fine.
2. No clogs in line. Besides the fact that it's not been used in so long I know this as when I switched pump wires I let it run for 50 seconds, and it did build up vacuum in the vacuum tank, and next time flushed just fine. But when I switched the wires back to previous status quo, the pump went back to non working status quo.
3. Pretty sure the problem is not the pressure switch on the vacuum tank as there is continuity at the switch (via multimeter) but when I manually pull back on the spring I loose continuity. This is the opposite of how I thought the system worked but I compared it to a working head and it's vacuum tank switch contacts reacted the same, so i guess the tank switch is ok.
4. Circuit breaker is on and ok....even swapped it with another head's breaker and it worked fine off the non functioning head's circuit breaker.
So, what is left ? A switch on the toilet pedal itself ?
Can a bad duck valve cause this ? (even though the pump created vacuum and flushed just fine when activated from another head)
What say ye ?
Dunno if this means anything but if I keep hitting the flush lever the water in the bowl starts turning a bit yellow....indicating to me that waste water is back flowing into the bowl when there is no vacuum.
The other three heads work perfect, and the holding tank is probably not half full.
1. Nothing wrong with pump itself. I know this as I switched wiring from one pump to another one and flushed it's head and the pump worked fine.
2. No clogs in line. Besides the fact that it's not been used in so long I know this as when I switched pump wires I let it run for 50 seconds, and it did build up vacuum in the vacuum tank, and next time flushed just fine. But when I switched the wires back to previous status quo, the pump went back to non working status quo.
3. Pretty sure the problem is not the pressure switch on the vacuum tank as there is continuity at the switch (via multimeter) but when I manually pull back on the spring I loose continuity. This is the opposite of how I thought the system worked but I compared it to a working head and it's vacuum tank switch contacts reacted the same, so i guess the tank switch is ok.
4. Circuit breaker is on and ok....even swapped it with another head's breaker and it worked fine off the non functioning head's circuit breaker.
So, what is left ? A switch on the toilet pedal itself ?
Can a bad duck valve cause this ? (even though the pump created vacuum and flushed just fine when activated from another head)
What say ye ?
Dunno if this means anything but if I keep hitting the flush lever the water in the bowl starts turning a bit yellow....indicating to me that waste water is back flowing into the bowl when there is no vacuum.
The other three heads work perfect, and the holding tank is probably not half full.
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