Hi,
I'm posting this here to hopefully aid in my furnace guy's diagnosis. As this may baffle him more than me.
I just got a new Heil 92 efficiency furnace and A/C installed a little more than a year ago. Until a month ago or so, I would hear what I assumed normal operation of the installed Little Giant VCMA-20ULS condensate pump, as when I was in my basement, I would hear a motor whirring every so often, and then see water being shot thru the tubing to the drain. Then it would be quiet again.
About a month ago, I heard the pump making weird noises, like it was laboring and noticed no water being sucked thru the tubing. I called my furnace guy, and he said to give it a couple good raps as the float may be stuck, that seemed to take care of the laboring sound, but still no action thru the tube that I could see.
About a week later, I noticed a puddle of water on the basement floor under the pump. I live in Cleveland, Ohio, so it's still heating season here. I popped one of the drain hole caps and started suction by mouth (nasty tasting water) thru a piece of tubing into a bucket until I got a good amount of it out. I had to do that a couple of times the next few days, and it was obvious it wasn't pumping, so I called my furnace guy who came out and replaced the pump with another of the same model. I assumed it was now working. However, I have not yet heard the motor run like it did when it was first installed a year ago, and haven't noticed water shooting thru the tubing. Yesterday another little puddle of water was on the floor and a little around the cap. I left a message to my furnace guy I may need this looked at again, but I told him I'll monitor it for a few days first. Now today, the tank is about half or two thirds full, and I didn't siphon any water out manually this time, so it must have worked.
I have the hunch it's either working intermittently or in a reduced capacity somehow. Again, no motor sounds or water seen rushing thru the tubing. Hard to believe two bad pumps in a row. Could something else be affecting pump operation or damaging the pump? The tubing goes from the pump which is basically ground level on the furnace, up about 7 feet to the ceiling and is brought down again into the drain, so maybe about 25 feet of tubing, 7 up,
10 or so across the ceiling, and about 7 down. He also snipped off the plug and spliced the electric cord somewhere in the furnace electrical system, instead of it going into an outlet. Thanks much, sorry so long, any help appreciated.