Sensor to disable mini-split in cold?

[ManCave]

Hi All,

We have an LG model LMU24CHV mini-split that is rated to run down to -4F. I'm not sure I trust them, but LG is telling me that if you turn it on when it's, say, -20F it won't damage the unit it just will not heat. Anyone know if it's true that it won't damage it?

Second question -- it does not have an outdoor sensor that disables it from running when it's too cold. Does anyone know if there is any sort of add-on device that can be installed to disable it when it gets really cold?

Reason I ask is we have guests and no control over what temps they might turn it on at.

 

[OH_Varmntr]

Regarding your 2nd question, yes, you can purchase a temp controller which is basically a thermostat that works at a wider temperature range that can be wired to disable the heat signal when the temps hit whatever setpoint you have it set for.

For example, you can run your inside thermostat signal that calls for heat through the low temperature controller contact so when it drops below, say 10*F (or whatever you set it at), it will open the heat signal circuit to the mini-split so it won't receive the run signal.

This temp controller for $16 has a sensing range of -50 to 250 degrees F and will do exactly what you're wanting to do.

 

[Done That]

Appears to me that its a rotary compressor (better than old recips) with a sump heater plus a suction accumulator so LG has certainly designed it to be pretty tolerant of liquid refrigerant slugging. Other stuff can come ito play though like proper system charge etc.

I'm no expert on those units, but I'm wondering what controller/system you have for it? Seems to me most of them allow you to go in and set an operation range and lock it just for this reason.

 

[justinjoyal]

Done That is right about the sump heater + accumulator greatly helping to reduce cold weather impact on the unit. I would not be worried about letting it run in the cold up to a certain point.

I am not familiar with LGs and this particular unit. Some systems do not respond well to inline temperature cut-offs. They will throw error codes and such. Others will work just fine...

 

[PoorOwner]

I don't think you need it, the mini split would have a thermistor on the outdoor unit.

 

[BillK]

LG is telling me that if you turn it on when it's, say, -20F it won't damage the unit it just will not heat. Anyone know if it's true that it won't damage it?

Why would you not trust what the manufacturer is telling you ??????? How on earth would any one here on the forum know any better than the people who make the equipment ????

Sorry, I just dont get some of the questions here.

If LG says its ok then leave it alone.

 

[justinjoyal]

I don't think you need it, the mini split would have a thermistor on the outdoor unit.

Some do, some don't. This LG unit doesn't seem to have one.