Glennhvac
01-20-2010, 07:07 PM
Wow almost 40 yrs in field and thankfully still learning. I had a RUUD 90 upflow locking out off and on and knew it was something in the drainage. It turned out that one of my hose connections was not quite tight enough. It would not leak water but was sucking in just enough air to cause the water in the recoup coil to swirl around the drain opening. Similar to what we have all seen happen with evap coils at some time or another.
The unit still had fine draft and all but what would happen on occasion is that when the unit shut down all that backed up water would try and drain. The darn fitting for the pressure switch hose is right at the drain opening and just barely above it. Sure enough the pressure switch tubing filled with water and if there was too much to be sucked back in the unit would shut down.
I have to admit this one was driving me nuts cause it came and went naturally in mild weather. When it hit 0 it condensed fast enough to actually catch it happening
The unit still had fine draft and all but what would happen on occasion is that when the unit shut down all that backed up water would try and drain. The darn fitting for the pressure switch hose is right at the drain opening and just barely above it. Sure enough the pressure switch tubing filled with water and if there was too much to be sucked back in the unit would shut down.
I have to admit this one was driving me nuts cause it came and went naturally in mild weather. When it hit 0 it condensed fast enough to actually catch it happening