Minisplit heat

[zedycus]

Hey all, first time post. A lot of great info here.

I had two mini splits units installed two years ago. One them is having issues when on heat. It blows warm air, and blows very low even when the remote is on the high setting.

I noticed the outside unit doesn’t come on like the second one mini split.

When I turn it on it stays on defrost mode for long time, 20-30 minutes.

When I turn the ac on, blows cold and hard. Fan mode blows hard. Only on heat mode. I’ve done self clean, tried resetting the power, tried different modes. Cleaned it as well.

Anything I can do, test out?

Anyone help I’d really appreciate it. Thanks in advance.

 

[rlitman]

What's the temperature outside? I've found that my mini splits work best between 5F and 25F. Below 5F, they still work fine, but there's got to be a low point where they start to reach their limits. But at 35F to 45F, the outdoor coils freeze up quickly, and then you enter defrost cycles and they really struggle to heat the space.

 

[zedycus]

Outside temps at night have been in the 40’s.

 

[justinjoyal]

Hey all, first time post. A lot of great info here.

I had two mini splits units installed two years ago. One them is having issues when on heat. It blows warm air, and blows very low even when the remote is on the high setting.

I noticed the outside unit doesn’t come on like the second one mini split.

When I turn it on it stays on defrost mode for long time, 20-30 minutes.

When I turn the ac on, blows cold and hard. Fan mode blows hard. Only on heat mode. I’ve done self clean, tried resetting the power, tried different modes. Cleaned it as well.

Anything I can do, test out?

Anyone help I’d really appreciate it. Thanks in advance.

First, try a power reset : turn off the breaker to the unit for at least half an hour and see if it resumes normal operation afterwards.

I doubt this will work though. I'm thinking it might be low on refrigerant, causing the indoor coil to not become warm enough. Most newer mini-splits have an "anti-cold" protection or whatever they call it, to avoid blowing cold air on the occupants of the house. This could be what's happening here.

A low refrigerant charge would also cause frequent ice build ups on the outdoor unit explaining why it would spend a lot of time in defrost mode.

 

[u2slow]

Have you checked the owners manual (equipment rating) for what kind of heat output you can expect at your current outside temps? How about the size of space each serves?

Not all heat pump equipment is designed to work well at cooler temperatures. Mine does not - it's an AC primary system.

 

[zedycus]

I have the exact unit in another part of the house. That one works great, blowing nice and hot.

Ive also noticed the vent door doesn’t open all the way. Opens 1/4 of the way.

 

[justinjoyal]

Ive also noticed the vent door doesn’t open all the way. Opens 1/4 of the way.

I'm pretty sure the coil is not reaching the proper operating temperature and the unit is in "anti-cold" protection mode, it would do exactly what you are describing.

 

[American Locomotive]

I suspect you believe it's staying in defrost because the fan is not turning? There are two sensors that control defrost - the ambient temperature, and the outdoor coil temperature sensor. They are usually looking for a certain temperature differential to be hit, then defrost initiates.

If either sensor is bad, it could cause the unit to get stuck in defrost.

 

[65ranchero]

Is there any flashing lights on the wall unit?
If so look in the owners manual on how to read codes and what they mean.

 

[PWC Repair]

Time to hook up the gauges......sounds like it's low on refrigerant.

 

[zedycus]

No lights flashing.

I had a tech come out and sure enough it was low on refrigerant. I had him purge the whole system and fill new. He felt it might be a micro leak. He added a sealer in the lines.

As of now, for far so good.

Thank you all.

 

[PWC Repair]

If it's tiny the sealer will fix it. I know of systems around here that were leakers that have been running for years now without adding refrigerant.