Condensate pan fills when AC unit is off

[nickfox45]

My condensate pan fills and overflows soon after opening the AC thru hull, even when the unit is off. Any ideas why that's happening?

I'm also working on figuring out why the drain hose isn't draining. But even if I solve that I need to fix the big problem if the condensate pan constantly filling.

[wagsea6b]

Is the water salty?

[sailorboy1]

there's a leak of course

[nickfox45]

Originally Posted by sailorboy1

there's a leak of course

Right! Any idea where?

[sailorboy1]

Originally Posted by nickfox45

Right! Any idea where?

hose, hose connection, condenser tubing, ......................... have you looked as those are the choices?

[sailorboy1]

is the seawater outlet open?

if closed maybe it is just the hose clamp

[redsky49]

Follow the sea water travel, from the inlet, through the strainer, and up to the condenser assembly. The condenser is the copper tube coil that the sea water enters. Check the hose and clamp at the entry, as well as at the exit of the condenser. Your leak might be at the point(s) of connection.

If source not found at the connection points, feel around the coil for a wet spot. It is possible that the tubing could have ruptured if not properly winterized, or one of the brazed fittings might be leaking.

If still no smoking gun, confirm that the water accumulating in the pan is sea water. Oftentimes, the condensate pan is not properly sloped, or the drain has become clogged, and normal condensation from the evaporator coil is not being properly removed. In humid environments, condensation will also form on various components of the AC unit - refrigerant tubing, dryer, etc., in addition to the evaporator.

Report back on your findings for further steps to take, if source not found.

[redsky49]

As a general maintenance item, the pan, as well as the evaporator coil face, the fan blades, etc., should be cleaned on a regular basis.

The challenge on a marine AC unit is access. It helps to have tiny hands (President Trump, where are you? ).

For the condensate pan, for example, it should be wiped down at least seasonally with an anti-microbial solution, removing all dirt and debris. Pan should be checked for level, corrosion and/or perforation and seam integrity (pans may be plastic, stainless, galvanized, etc.).

In the event that condensate pools in the unit, accumulated dust and dirt may float towards the drain opening, clogging it at the point of connection to the drain tube. These are typically only a 1/2" or 5/8" dia. opening, and can easily clog. If you can locate the condensate drain line, try blowing air back through the drain line in an attempt to dislodge any blockage. Perhaps you have a kink in the line, especially if using non-reinforced tubing.

Hope this gets you a start toward finding the problem.

[leboyd]

It is possible that you are low on freon. When low, this causes the coils to actually freeze - you can see the ice. When off, the ice will melt, showing symptoms like you are seeing (assuming it's fresh water).

[nickfox45]

Originally Posted by redsky49

Follow the sea water travel, from the inlet, through the strainer, and up to the condenser assembly. The condenser is the copper tube coil that the sea water enters. Check the hose and clamp at the entry, as well as at the exit of the condenser. Your leak might be at the point(s) of connection.

If source not found at the connection points, feel around the coil for a wet spot. It is possible that the tubing could have ruptured if not properly winterized, or one of the brazed fittings might be leaking.

If still no smoking gun, confirm that the water accumulating in the pan is sea water. Oftentimes, the condensate pan is not properly sloped, or the drain has become clogged, and normal condensation from the evaporator coil is not being properly removed. In humid environments, condensation will also form on various components of the AC unit - refrigerant tubing, dryer, etc., in addition to the evaporator.

Report back on your findings for further steps to take, if source not found.

Thanks for your suggestions. I've determined that the pan doesn't fill unless the seawater thru-hull is open, so I know it's not a freshwater leak. I traced the entry all the way to the condenser, but the inflow for that is below where I can see. I can't see or feel any obvious leaks from there.

If I turn on the unit, the pan will drain overboard thanks to the pump. For now, my plan is to just leave the thru-hull closed when the AC unit is not in use, so I can continue to troubleshoot.

[thinwater]

Depending on where the seawater leak is, there is a fair chance that it will get on something it should not and corrode the AC unit to trash in a season. Even when off, it will dry up to salt, which is worse.

You better find the leak and wash off the salt.

[Cadence]

Originally Posted by nickfox45

My condensate pan fills and overflows soon after opening the AC thru hull, even when the unit is off. Any ideas why that's happening?

I'm also working on figuring out why the drain hose isn't draining. But even if I solve that I need to fix the big problem if the condensate pan constantly filling.

My dumb guess is an algae build up in your drain. A dose of Clorox once and awhile solves that.

[OS2Dude]

Tell us how your unit is configured. Our unit controls the raw water pump, so if the A/C is off, so is the pump. Our input thru hull is lowest (Below water line), then the pump (about at water line), then highest is the the coil (Above water line). Outflow is coil (highest) to output thru hull that is a few inches above the waterline.

Two issues I see: Where is the water coming from and how is it getting into the condensate pan?

Is the pan lower than the input thru-hull? Is the hose connection to the coil good and tight on both ends? (Inflow and Outflow) No tears or breaks in the hose at the end of the coil connections? Is the pan drain connected to the outflow thru hull? If so, is there a back-flow preventer or a siphon break? You could be siphoning water into the boat via the drain line from the outflow thru hull, or from the inflow if water pressure alone is filling the coil once you open the seacock. (How high is it compared to the water line?)

Hope you solve that mystery soon.

[icemate]

Originally Posted by nickfox45

My condensate pan fills and overflows soon after opening the AC thru hull, even when the unit is off. Any ideas why that's happening?

I'm also working on figuring out why the drain hose isn't draining. But even if I solve that I need to fix the big problem if the condensate pan constantly filling.

Good chance your unit is low on refrigerant. This would cause evap to freeze, hence when off, ice melts. Have HVAC Tech check charge.