enter image description hereWe had a Gree mini-split system installed in our condo located in the SF Bay Area in 2016. Since the location of the 3 units (both bedrooms and living room) are not mounted on external walls, Sauermann SI-30 condensation pumps were installed in the attic. Within the first month, one of the pumps needed to be replaced as it had failed, causing damage to the wall below the unit. Apparently, the tech forgot to dampen the vibration with the rubber mat when he reattached the new pump to the attic floor. So, I decided to hang this pump and the other two ~ 1ft above the attic floor instead (increased pump lift from ~3 ft to ~4 ft)

We have recently noticed the paint has bubbled along the wall directly below two of the units, which seems to indicate some leakage within the unit. It's not certain whether the pumps have failed. I have read great reviews of the Aspen Micro V pump for being super quiet and very reliable. Would appreciate any advice as to whether the SI-30 pumps should be replaced with these Aspen pumps and also if they should be relocated within each unit rather than in the attic, not certain whether extreme heat in attic might be causing pumps to fail! Also would appreciate any referral for a good tech in the SF Bay Area to call to do the work!

  • I haven't seen condensate pumps that far above the pan, this would require them to pull a slight vacuum. I have been lucky and been able to run drain lines outside the home. This pump is rated for 10' so it should work. Is the discharge line elevated? The only other thing I would guess at would be if you are exceeding the rate the pump can flow when pulling from below at times causing the moisture. – Ed Beal Aug 20 '18 at 17:50
  • What's underneath your house? Crawlspace? Slab? Is there any way to create a small condensate tank inside the mini-split with a limit switch to shut it off if the condensate tank fills? My dehumidifier does that, and it's $100. It wouldn't surprise me if the mini-split maker even had a kit for that. – Harper - Reinstate Monica Aug 20 '18 at 20:08
  • @Harper: Our unit is on 2nd (top) floor of complex. The 3 pumps discharge into the pvc pipe which runs through the attic vent and down the side of the building. I'm assuming that there is a condensate pan within each wall unit, but don't know as not sure how to open it. Not even certain if there are float limit switches to shut off A/C to prevent overflow of pan. – Grant Aug 20 '18 at 21:34
  • Why in the world can the condensate piping not simply be run down?! – ThreePhaseEel Aug 20 '18 at 23:08

The instructions for the pump include some test and troubleshooting steps, did you try these?

Initial operational test

  • First clean the condensate tray of any debris leftover from manufacture or unpacking od the air handling unit
  • Pour water into the condensate collection tray (a squeezable plastic bottle, ACC00401, is available)
  • Check that the pump unit starts & then stops as the water level decreases.
  • Check safety switch by continuing to pour water until the alarm triggers (cutting off the compressor, generating an audible or visual alarm etc)

The sump/detection unit must be cleaned and serviced at regular intervals in accordance with the degree of pollution existing witin the pump operating environment.

If the pump doesn’t start, check the wiring and incoming power supply.

For any problem, check :

  • the discharge lines are neither obstructed nor kinked,
  • the float inside the detection unit is not blocked
  • the hydraulic inlets nor outlets are not obstructed

If the pump is running continuously (>1min), check:

  • the discharge height is < 10 m,
  • the pump is suitable for the capacity of the air conditioning unit,
  • while starting of the pump, the flow of the water poured into the collection tray was not too high (ex: 1l in 30s=60l/h >>20l/h).

If the pump is running continuously and does not suck water, check that the suction hose (hose that connects the pump and detection unit) is connected and air tight.

If the pump cycles continually or does not shut off, check the detection unit is mounted level.

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  • I'm afraid I'll need to have a qualified tech perform the troubleshooting steps that you list. I was hoping to get additional feedback as to whether the temperature in the attic might be a problem for the pumps, and if so, whether I should have the pumps relocated within each unit and push the condensate up into the attic rather than pull a vacuum. Any feedback on the Aspen Micro V vs the Sauermann SI-30 would be helpful too! – Grant Aug 20 '18 at 21:39
  • San Fran is not that hot of an area, even on the few 100 degree days this should not be an issue. The issue is condensate pumps they Always fail, it may take 5 years or longer but I have never seen one last , when in an attic I have used water sensor pads that shut the control power off when they get wet this will be the best option because your pump will fail in time. – Ed Beal May 1 '19 at 13:50

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