Mini split mystery unsolved

[pbajon]

Hi everyone. This is my first post to this Forum. Looks like the problem I will describe was never been presented in any Forum that I have visited. It's about the lack of the presence of the water in the drain hose of my mini split, AND lack of leaking of the water from the indoor unit.

The system is one year old. It's Sanyo KS0971 (outdoor unit) and Sanyo KS1271 (indoor unit). When the system was installed everything worked perfectly. Nice cooling, quiet operation, the excess of the condensed water was freely flowing without any problem. Since this is only the Air Conditioner and NOT Heat Pump I was not using it throughout the winter.

Hot Spring days arrived and it was the time to turn the unit on again. At the first glance all was well, BUT after few days I have noticed that the indoor unit is unable to cool the room to the lower temperature then 76. Outside temp was like 90 degrees. I went outside to check the compressor. It looked like everything was working fine, BUT this was the first time I have realized that the drain hose was totally dry. We have installed a clear vinyl hose just in case if we would need to double check in the future if the drain hose is clogged. All the lines coming from the indoor unit are covered by the line set covers.

OK, the big question is:

Why there is no water draining from the indoor unit? To me it looks like in order for the entire mini split system to work properly the condensed water should be draining outside, UNLESS there is no water being developed.

Something is telling me that either there is a freon leak somewhere, or the condencer is messed up. Or maybe even something else. I don't know. I remember my first car. When the freon level was low the the air coming through the vents was warm. As soon as the system was charged up again with an additional freon, the inside of the car became like a freezer.

Based on technical manual for these units I have run a self-diagnostic test in order to see if I would get some error codes (mulfunctioning part). Nope. The test results didn't show any failed component of the entire system.

The guy (HVAC pro) who has installed the unit moved out, and so far nobody from my town (HVAC businesses) can't figure out what's wrong. Most of them specialize in certain models of mini-splits (Mitsubishi, LG) and nobody is familiar with Sanyo products. In other words they don't wanna touch it.

So, where should I start when it comes to (FIRST) identifying the source of the problem, and (SECOND) fixing it.

Many thanks in advance for your help and suggestions.

 

[79firebird]

Chances are its low. Ive had that prob a fue times. Local place installed it call back every year not working low on fluid. So they top up check at the bottom for leaks thats it. Found the leak where they joined 2 of them togther

 

[ghnl]

If it was cooling properly and dehumidfying the indoor air then either the condensed water would go out the drain or it'd back up and run down the inside wall.

If it is not cooling properly (likely low on refrigerant) then you'll see the symptoms you describe.

 

[pbajon]

Thank you, guys, for your thoughts. I have called the local HVAC company and they might come over on Monday to take a closer look at this. I agree, if the entire system works ok except not cooling enough then it might be low on freon. We'll see what will happen on Monday. I'll post the update on Monday.

 

[Grumpy365]

Moisture won't condense on the coil until the coil temperature is lower than the dewpoint of the air.

Your coil isn't getting cooler than the Dewpoint. If / when the coil gets cool you will see the water run out of the drain.

 

[pseudorealityx]

Moisture won't condense on the coil until the coil temperature is lower than the dewpoint of the air.

Your coil isn't getting cooler than the Dewpoint. If / when the coil gets cool you will see the water run out of the drain.

The problem is, unless he's in a desert, the coil SHOULD be below the dew point.

 

[pbajon]

Well, guys, that was my other thought. A lack of enough humidity inside of the house. Last year we have replaced the entire central AC of the house with a brand new unit (American Standard). So far it's been working great. Lower electric bills, cooler home, and also DRYER home!

Right now, when I check, the humidistat it is 48% humidity in the house. Outside it's probably around 85-90%. So, I thought that if there is not enough humidity in the house then I would not see any water coming out from the drain hose of the mini split unit. But then, how would you explain the fact that last year (during entire Summer season) the water from the mini split would drain every day. And the amount of the humidity in the house was exactly the same like today.

Something is not right. Can't wait to solve this problem. Thanks again for your kind thoughts and suggestions.

 

[rlitman]

On a separate note, you should not have a clear drain line. You want something that blocks all light. There is no need to see water IN the line, if it is coming out the end.
A clear hose that lets light in, is inviting algae to clog the hose.

 

[pbajon]

UPDATE.

OK, the HVAC Pro come in and double checked the entire system. There was only 50% of freon in the lines. Part of this problem was related to the first guy who has installed the system. He purpously removed some of the freon claiming that this would make the condenser coil cooler and thus the indoor unit will blow cooler air into the room.

The guy who came today told me that if the entire system doesn't have enough coolant (freon), then system is not well balanced and does not produce enough cool air. So, he has filled the entire system with additional amount of freon (1 pound).

After approximately 20 minutes the indoor unit started to blow much cooler air into the room. We also have noticed some water drops coming out of the drain hose. That was a good sign of moving into the right direction.

The HVAC technician who come today advised me to keep an eye on the indoor unit (much cooler air should be coming into the room from now on), and if the water will be coming out of the drain hose. He also checked the drain hose and it was perfectly clean. No clogging issue.

So, it looks like you guys were right. Low level of freon in the system caused this warm air coming into the room from the indoor unit.

If the earlier symptoms will come back, the technician will check again the amount of freon in the system. If the amount of freon will get low again, then it means we have a leak, and then we'll try to locate it and fix it.

For now all things went back to normal. Let's keep our fingers crossed.

Again, thank you all for your kind suggestions. I do appreciate it very much.

 

[ghnl]

Thanks for the follow up. Confirms our suspicions and will help others make the right diagnosis.