I have water accumulated in my basement, that I squeezed out using towel. It was about 8 gallons of water in all. The only source I can see is the furnace whose surrounding is wet but I have never seen a running water from there other than being wet.
Previously (last year) I have seen water accumulated once due to what I thought was excessive rains but this time, it has been very dry outside.
Does this picture tells anything if this is the furnace indeed? Is the fix easy?
Update
I followed up with the answer and filled condensation pump with water. The motor does start and the tank gets emptied but what I noticed is the water starts to seeps through the furnace. I have provided pictures with red circles where water seeps.
It was difficult to determine if the water really gets out through the transparent hose which is very yellowish at this point. I watched several videos on youtube and typical issues seems to blockage of valve. Now I am not sure if that's the case given the water seeps through the furnace after pump action? Could the pump be pushing it in backward direction due to blockage?
Do you think there is still good chance I check for blockage and that could fix the issue or get new pump?
Update 2
I troubleshooted further and opened the condensation pump. The tank was extremely dirty dust collected over time over time and stuff hanging to walls and floaters. I guess that could block the valve if this stuff is getting pushed out.
I clean it, cleaned the valve and tested the condensation pump by itself and it's working great. When I fill it, the springs up the water with nice power as i have seen in youtube videos.
I put it back but unfortunately, this still didn't fix the issue! The water oozed out from furnace parts higher up after pump action.
Best Answer
In a comment you said,
Assuming you're talking about a whole-house AC unit, what's outside is the condenser. There's another half to the system - the evaporator. it sits inside your "furnace" and cools the air forced over it by the circulation fan in your furnace, which in turn circulates through your ducts and cools your house.
AC evaporators tend to collect significant condensation, to the point that furnaces with AC fitted will always have a condensate pump to collect and dispose of the condensation. You said you mopped up about 8 gallons of water - where I live, that would be a fairly typical volume for a few days of cooling in a typical home. In other words, it's not really that much.
As mentioned by comments, the white box on the side of your furnace is the condensate pump. The hard white plastic plumbing going into the top of the pump is the drain line, which drains the condensate from the evaporator coils into the pump. The pump has a switch inside it that turns on as it fills with water, and the water is pumped out through the smaller-diameter translucent hose coming out the top of the pump. A good place to start troubleshooting this problem is to pour water in one of the empty holes on the top of the unit, and see if it runs and empties itself out.
If it does not run, make sure it's plugged in and has power. If it is, the pump or the switch inside it may be dead. It's not expensive to replace a condensate pump.
Condensate pumps have a check valve on the fitting for the output line, it's possible the check valve is full of debris or clogged and causing the pump to overflow even if it's running. So check that as well, if you can't troubleshoot otherwise.
If the pump is clean and functional, you may have a problem inside your furnace - the tray that collects condensate from the evaporator coil may be damaged (rusted, or there may be debris collected on it that's causing it to overflow instead of properly drain. If you're not comfortable opening the furnace up to check for these problems, it may be time to call a professional.