Mini-split outside temp advice.

[Del Davis]

I am having an issue with my mini-split. I have a Friedrich Breeze Series BR0412W1A unit that came with pre-charged lines. It works great all summer to cool a little under 2000w of lighting, but when it gets cold outside it starts to freeze up.

Last night it went down the upper 40s outside and when I woke up there was lots ice where the lines connect to the outside unit and water dripping from the front inside. I turned it off for a while then ran just the fan option till it thawed out and now its back to cooling just fine. The model I got lists low temperature operation as one of its features so I was expecting it to work in temps under the upper 40s.

I have had it for almost 2 years and it did the same thing last year. I ended up having to shut down for a few months during last winter. It wasn't the easiest to install by myself and its possible I kinked the lines or something. Would an issue with the charge cause problems in the cold but still work great in the summer? I am in a non-med state so I was hoping to avoid having to have a tech come out to look at it.

Thanks for any help!

 

[growshopfrank]

What you need is a low ambient kit

 

[Del Davis]

I called Friedrich and they said the unit should work in colder temps then it is and they don't have an add on low ambient kit for my model. They suggested I have someone come out to look at it.

 

[growshopfrank]

My bad just looked up the specs on your mini and it may already have the low ambient feature. If this is the case there may be a issue with the unit like low refrigerant.
As much as i hat to type this they might have a point in having a pro check it out.

 

[Asslover]

Low refrigerant levels will do that. Did any freon leak out ever?

 

[queequeg152]

you just froze the evaporator supply line.

wrap it in "foam rubber" insulation, r-4 1 inch + thick stuff, then foam rubber tape wrap.

you also probably froze the evaporator coil.

be careful here. its possible to "slug" liquid phase refrigerant to the shittier equipment. most new systems have TX valves that would prevent this, but oldr134a systems may or may not be cap tube based.


you might consider a low temperature lock out kit to prevent this "slugging" condition. its basically a bimetallic theromstat button that clips onto the suction line from the evaporator returning to the condensing unit.

it basically interrupts the thermostats call for cooling, forcing the unit to shut down untill this thermostat detects normal temperatures again.

 

[queequeg152]

so if the above is true, your ac unit is pretty much a 'dumb' system like most cheaper ac systems... lacking any ability to react to changes in head pressure or outdoor air temps.

additionally,its not typical system from what i can tell. its probably going to be difficult to retrofit anything into it, owing to lack of space one would expect inside a conventional outdoor condensing unit.

if all of the control circuitry is handled inside a single PCB with shitty surface mounted transformers and Gaylord surface mounted relays, it might not be possible to do anything to the control scheme, so crack it open and look before you buy anything.

check to see if the fan has multiple speeds. im guessing it does not, but what ever.

if it has multi speeds, manually slow it by jumping the leads, and monitor the evaporator line set temperature with a clamp on thermistor/thermocouple or taped on therister button or thermocouple probe.

if its still too cold, or is not multi speed, you have to come up with another way to keep the condensing unit from over cooling the refrigerant. ive heard of people wrapping the conensing units with mesh fabric... effectively reducing the airflow by increasing the resistance that the air encounters. i would not recommend this without a great deal of caution as its a very crude approach and the mesh material could concievably collect dust and debris or perhaps even freeze solid with sleet or snow?

another option would be a new fan motor, or smaller diameter fan blade. both of these though are not much better than the mesh though. and a smaller fan might spin faster(be louder), depending on what sort of motor is being used here.

the suction line(fat) pipe leaving your evaporator should be around 40 degrees F give or take 5 or so degrees. it should not drop below freezing for obivious reasons.

the air leaving your evaporator should be substantially warmer than the evaporator itself, usually around 55 degrees.

 

[queequeg152]

oh yea... you should also increase the evaporator fan speed when temps are that low.

more air flow will remove more heat from the evaporator, and hence keep the refrigerant returning to the compressor warmer.

 

[Granger2]

I'm sure it would be lotsa work, but if it came down to calling a tech, you could remove the whole kit and kaboodle and take it to a tech. I'm still wondering about your 1st post where you said you may have kinked the line. Did you, or didn't you? You'll need a good story about why your cooling in the winter time, so you don't stutter and uhhh... if asked. Good luck. -granger

 

[Del Davis]

Thanks for the suggestions, I appreciate it. I'll put insulation on the lines outside and look into the other stuff. I turned off a 600w and am just running 1000w in the flower room now and raised the AC temp a little to see if that helps. I run co2 so a little higher temps shouldn't hurt to bad.

When I was installing it the evaporator fell a few feet one time while I was on the other side of the wall feeding the line. It jerked the line but didn't put a 45 in it or anything. Honestly, I don't really know enough about it to tell if something happened, nothing visible came out and it worked fine after I finished installing it.

The lines came pre-charged and I don't know if I can unhook them to uninstall it and take it to somebody and then just re-hook them back up.

If it gets worse or causes me to close down for too long in the winter I can get a new unit. Can low refrigerant be caused by something that is easily fixable or is it an indicator that something is damaged and I'm going to need to replace it at some point anyway?

Thanks Again.

 

[queequeg152]

Thanks for the suggestions, I appreciate it. I'll put insulation on the lines outside and look into the other stuff. I turned off a 600w and am just running 1000w in the flower room now and raised the AC temp a little to see if that helps. I run co2 so a little higher temps shouldn't hurt to bad.

When I was installing it the evaporator fell a few feet one time while I was on the other side of the wall feeding the line. It jerked the line but didn't put a 45 in it or anything. Honestly, I don't really know enough about it to tell if something happened, nothing visible came out and it worked fine after I finished installing it.

The lines came pre-charged and I don't know if I can unhook them to uninstall it and take it to somebody and then just re-hook them back up.

If it gets worse or causes me to close down for too long in the winter I can get a new unit. Can low refrigerant be caused by something that is easily fixable or is it an indicator that something is damaged and I'm going to need to replace it at some point anyway?

Thanks Again.

its just freezing, i dont think you have any charge issues here.

you could get a harbor frieght ac manifold + adapters+ piercing saddles(probably) and check youself if you are concerned. that unit is probably r134a... so the shiitty harbor freight gauges should work; i dont think they sell anything for r410a.

from what im reading... the unit is literally just cooling TOO much. the refrigerant is dropping below freezing and freezing your evaporator coil and lineset.

like i said. a frozen evaporator coil can damage equipment.

even if the unit has a TXV... freezing the evap willl put stress on your compressor.

 

[iTarzan]

Turn off the a/c in the winter and use the cold outside air to cool the room or air cooled hoods.

It would be great to have the outside unit moved into the basement or other inside room in the winter. It would help with heating the house while cooling the room. They should make one like that. You flip a switch that chooses either the outside or inside coiling coil/unit.

You could have two units. One on the outside for summer and one on the inside for winter.

Enough stoner ideas. Use outside air in the winter.

 

[Asslover]

That unit is R410A...
To the OP, You CAN disconnect and reconnect the line set 5X before you have to add freon. Every time it's disconnected a small amount of Freon comes out.
Your unit should easily be able to cool at much lower outside temps than you're dealing with.
On the Air Handler, is there a light flashing on it?

 

[queequeg152]

i take back everything i said beffore.

i took a few and researched this unit... its a fucking mini split with a precharged lineset. thats it.

it should be able to cope with this temperature easily.

my apologies. i thought this was basically a split window unit. idk where i got that idea.

this thing should be able to manage head pressures or refrigerant temperature by varying the fan speed quite nicely.

if i had to bet... your evaporator coil is fouled with shit and is freezing due to poor airflow. check it and try speeding up the cassette fan as well.

this thing is an inverter minisplit so there should be some diagnostic indicators like asslove suggested, should start there.

 

[shredGnar]

I built a simple 2 x 4 frame around my outdoor unit. Then put plywood over it to restrict air flow. I add and take pieces off to adjust how much can be drawn thru. I can run into negative temperatures no problem.

Seems wasteful, but It's better than fucking up my humidity and ppm %'s.

 

[Redbuddz]

Turn off the a/c in the winter and use the cold outside air to cool the room or air cooled hoods.

It would be great to have the outside unit moved into the basement or other inside room in the winter. It would help with heating the house while cooling the room. They should make one like that. You flip a switch that chooses either the outside or inside coiling coil/unit.

You could have two units. One on the outside for summer and one on the inside for winter.

Enough stoner ideas. Use outside air in the winter.

I agree with everything Tarzan said. Why not just use the outdoor air? in the winter? It's not cheap to run AC

 

[shredGnar]

I don't, because personally the air is very dry where I live. My plants do much better when the humidity is in line with temps (VPD) and I supplement co2.

I don't think I could manage that using outdoor air.

The increased yield more than makes up for the extra electric costs.

 

[Del Davis]

So, I'm starting to think it might not have as much to do with outside temperature. It started doing it again during the day when it was warm out. I have a setup that sends me a text on my phone if the room gets over 90* so I can go and deal with it right away. It seems like it just cant keep up after a while when all the lights are on.

When I got to it the fan in the evaporator sounded and felt like it was chugging and spurts of air were coming out as opposed to a steady stream. It also spit out a few small pieces of ice. I shut it down and waited 5 minutes or so then turned just the fan option on and after about 10 minutes its back to blowing strong and I can switch back to AC. I didn't notice any error codes when it happened but I may of just shut it off right away without looking close enough. Ill look for one if it happens again.

The evaporator coil and the filter over it are both clean on the side I can see. The fan did have some dust on it which I was able to clean off with a pipe cleaner, It didn't seem like enough to effect it too much but maybe it will help. I also found a turbo option on the remote that increases the fan speed which I just turned on.

While the idea of free cool air from outside in the winter sounds nice, I like having a sealed environment where there is a lot more control over dialing in the temp, co2, humidity ect. Also I'd rather not cut holes in the walls and change my whole setup for a few months in the winter.

 

[Treetroit City]

I have two Friedrich Breeze units and they work down to at least -10F

 

[MrBelvedere]

Hire a pro