Johnson Sump Tank

Johnson Sump Tank

Information

The Johnson Multiple Port Shower Sump collects water from the sink, which runs through a plastic filter tube before entering the sump tank. Once the water reaches a certain level the pump (red item in picture below) is triggered by a water level switch (black item in above below).

The sump needs periodic cleaning, depending on how often water is sent into it and how dirty that water is. It is recommended not to drain solid matter into the tank. Many use a bowl in the sink and throw the contents of the bowl away outside the camper. Cleaning the tank and, more importantly, the filter tube should keep things running smoothly.

Johnson Sump Pump

 

Problems

Sump Not Emptying

 

  • Pump Failure
  • Water Level Switch Failure
  • Clogged Exit
  • Grey Tank Full

 

Pump Failure

No noise at all from the pump would indicate a pump failure. Check the break for the pump on the camper breaker panel. Use a multimeter to test the power at the pump. (James Young)

If the pump ‘whirs’ but is not pumping out the water then it may be clogged. Turn off at the breaker and carefully use a small thin item to clear the intake.

(James Young)

 

If the pump ‘whirs’ but is not pumping out the water then it may have an air pocket. This often happens after cleaning, especially if cleaning involved removing all of the water in the sump. It is a bit hit and miss but cleaning around the pump intake (base of the pump) with a cloth usually either moves air or pushes water into the pump. It often takes me a few rounds of cleaning / switching the breaker back on to get the pump to drain the sump tank.

(James Young)

 

The inside of the motor can be cleaned and is sometimes the cause of the pump whirring but not taking up water.  The image below shows the black pump top and also a black tab with the screw in it. This tab is the catch to secure the motor. Pull the tab forward and turn the motor counter-clockwise then up to remove it. Check the impeller on the bottom for gunk.

(Dennis York)

johnson sump pump

Tips

Protect Sump Tank Cover

The sump tank cover can be prone to splitting at the screw holes. It is important not to overtighten the screws. The force can also be spread over a wider area by using a washer. I tighten the screws until the washer is not moveable underneath the screw head. Then back off the screw very slightly.

Ensure the wires leading out of the tank are neatly aligned when replacing the cover. The cover should fit cleanly over the top of these, the wires able to lay flat on the case underneath.

(James Young)

Sump Tank Cleaning

An old toothbrush of a bottle brush are useful for getting around the pump and switch.

(James Young)

 

After cleaning, run water into the sump tank to ensure the pump is working correctly prior to re-installing the cover. The pump often requires a bit of debris removal / air pocket removal after cleaning. Ensure it all works before installing the cover.

(James Young)

 

 

Johnson Macerator Pump

Johnson Macerator Pump

Information

The Johnson TA3P-10 Macerator Pump was originally designed for lavatory waste. I assume the benefit to the grey water tank is that any food particles from the sink, or any hair etc from the shower, get macerated and do not block the pump. 

The pump pulls grey water directly from the grey water tank, through the pump and out of the grey water hose.

Problems

Tank Not Emptying

  • Pump Failure
  • Pump not priming
  • Macerator Blocked
  • Clogged Exit
  • Grey Tank Empty
  • Camper at an angle that prevents remaining grey water from emptying

 

Pump Failure

No noise at all from the pump could indicate a pump failure. Check the break for the pump on the camper breaker panel. Use a multimeter to test the power at the pump.

(James Young)

 

Pump not Priming

I’ve had difficulty getting the macerator pump to prime (pump whirring correctly, but not picking up water) and apparently, others have as well. Solved this problem by putting suction on the pump outlet with a simple transfer pump and switching macerater pump on.

(Joseph Braun)

 

Macerator Blocked

If the pump ‘whirs’ but is not pumping out the water then the macerator may be clogged / stuck. Sometimes this emits a squealing noise.

If that happens, switch off the pump, use a small electrical screwdriver to remove the top cap of the Grey Macerator Tank. This exposes a metal block with a slot for a flat head screwdriver, I assume this is the auger.

Using a flathead screwdriver rotate that metal head to turn the shaft and free the blockage. You can turn clockwise or anti clockwise BUT whatever way you choose finish by turning it a turn anticlockwise. I believe this sets it up in some way but not sure how.

It was easy enough, worked first time when I switched it back on. Instructions are in the XP manual, thankfully Claire thought of looking there.

(James Young)

 

 

Camper Angle

Earlier models have a pump hose attached to the side of the tank. This causes a mixture of air and water when the grey water levels gets too low. Or, worse still, just air of the camper is angled away from the hose. In this instance, placing some blocks under the wheel diagonally opposite where the sump hose is attached will ‘push’ all the water up to that end and allow the pump to empty cleanly.

Later models have the hose inserted in the top of the tank, almost touching the bottom of the tank. This helps reduce the water / air mixture. This fix has been done on some early campers, look for tips elsewhere in this post.

(James Young)

 

Tips

Keep Grey Tank Clear of Debris

Keeping the grey tank clean and clear of larger debris will be beneficial to the grey tank macerator pump. Some use a washing up bowl in the sink, throwing the water away outside the camper. This reduces food particles and such from getting into the sump tank and then the grey tank; meaning obvious benefits to both.

(James Young)

Grey Tank Cleaning

Running a grey tank cleaner through the system will help reduce grey water ‘smells’ especially in hot weather. Regular cleaning helps, regular emptying helps too.

(James Young)

Stay ECO to dump anywhere

Using environmentally friendly soaps, detergent etc and not adding anything toxic to the grey tank means that you can dump it anywhere, within reason. It is worth noting that even ‘environmentally friendly’ soaps like Meyers or Dr Bronners can be bad for lakes, streams, rivers etc. So, if you do ‘wild dump’ do so away from a water source.

(James Young)

Hose Nozzle

Our fresh water drain hose and our grey water pump hose finished with a ball valve only. This meant the water sprayed out of the end, rather than coming out in a nice stream.  A bit messy with the grey and the fresh water was awkward to get into small holes, like adding some to the toilet for example. We added a connecting screw thread, usually used for connecting two threaded plumbing items. It makes a nozzle and therefore a nice steady stream of water.

Another option is to add a hose connector to the end. You get a steady stream, plus an option to add an additional hose should you need to. 

water hose nozzle

(James Young + Gerhard Faessler)