Will audio gear be ok in unheated house

What part of the country?

It will be fine.

They make moisture absorbtion media (comes in a small bucket) that people use in boats when they over-winter (shrink-wrap) their vessels. Certainly an option. Google "DampRid".

I’d look into that, but your plan with sealing the equipment up with a dessicant inside would also work.

Just let the equipment fully warm up prior to use.

I have wrestled with this issue also. It is a pain in the neck bringing gear back and forth. Like you, I am mostly concerned about theft. What you plan to do sounds good and going forward I may try it. I swear my integrated tube amp gains 5 pounds every year.

"when I leave in the fall for theft worries"

- So you are changing your mind about this reason?

is there a big closet or small room with a well sealed door that you could put the equipment and a small space heater in, set to low heat?

+1 thecarpathian

Winter or cold temps can be very rough on capacitors, particularly old ones. If they freeze and warm-up they might fail or lose integrity/ Probably due to very minor expansion and contraction.

Yes, fluctuations in temperature and humidity in a non climate controlled environment can be detrimental to any part of those speakers including the cabinets and veneer. 

@elliottbnewcombjr I think the National Fire safety association would take exception to your space heater recommendation, they aren't intended to be lest on for long periods and certainly not unattended 

I'm not suggesting a toy heater.

entire homes have electric baseboard heat, they are left on low for winters all over the world, Countless people from the North East go to Florida for the winters

quickie search, this one is plug, or approved for hard wire

a thourough search will find many safe options

all you need is a closet with an old school incandescent light bulb in it, left on should be enough to keep the closet warm ie above freezing and dry. And not run up your power bill. 

Marine supply stores offer low wattage heater sticks expressly for dehumidification. They're not expensive and far safer than a room heater or light bulb. I'd also consider making the closet more theft-resitant with a heavy duty door, hinges, and lock. At a minimum, line the inside of the door with 3/4" plywood and install a deadbolt. It won't stop a determined thief, but it will slow and hopefully discourage them. Look

@glennewdick ....with some simple insulation and a fresh bulb, your concept ought to fly nicely....the only fly in that soup would be an extended power outage....but with desiccant.in that space as well, ought to be as safe and sound as possible..👍.

@dill

"when I leave in the fall for theft worries"

- So you are changing your mind about this reason?

Your quote left off most of the original sentence.

It said:

when I leave in the fall for theft worries, but mostly because I am not sure the equipment will be OK in an unheated house in an often damp environment until the late spring when I return.

Theft worries are not the primary reason for moving the equipment.

I let my equipment, including tubes, get down to around 55 degrees fahrenheit in the colder months of the mid-lower South. If in the higher North, I'm not sure I would trust in house temps in the 20s. Friends have a camp in Adirondacks that is closed for the winters. I'm sure the inside temps get into the low 20s but they only have some basic TVs that can be replaced cheaply but those have stood up well. 

Do not put your electronics in plastic bags. Those packets can only do so much and then they are done. And moisture over time is very bad.

"Theft worries are not the primary reason for moving the equipment."

- Yes, I understand that, however since he mentioned it, maybe it should be ...

I have a cabin in Michigan’s Upper Peninsula, it is relatively new construction well insulated and well sealed. I have some older equipment, Antique Sound Lab tube integrated, older DAC, and Vandersteen 2Ci, which I have been using there for several years. In the winter the cabin is unheated, and it typically is in the 30’s inside.  Only in the coldest weather does it drop into the 20’s inside. I know this since I have a weather station that has multiple sensors so I can monitor indoor and outdoor temperatures and humidity from my primary home. I do put out desiccant, specifically Damp-Rid, but it doesn’t do much. In the spring there is still desiccant and some liquid (when the desiccant absorbs moisture it forms a weird liquid in the bottom of the container).  The humidity is typically 50% - 60%, not great but ok. So far no issues with any of the equipment. If you know the humidity is higher or you just want to be extra safe one alternative is a desiccant from hydrosorbent. I’ve used it to protect woodworking tools. You do have to put the item in a sealed container for this to last several months, might be an issue for bigger components, but it works for small items.  Good luck!

Rather than using garbage bags, use moving size cling wrap to wrap your gear. It can be purchased on Amazon or at Home Depot. The 20" wide rolls work well for audio components and speakers. I use it to store my audio equipment that is not currently being used. I wrap two or three turns length wise and width wise and it forms a good tight seal that will keep out insects and moisture from anything short of full on flood submergence. I also use it for extra shipping protection when I sell gear.  

Beginning to sound like it's just easier to take your speakers with you!

Peace of mind knowing they're safe.

In the long run, leaving your stereo equipment in an unheated home where the outside temperature drops below freezing and/or below 50 degrees where dampness exists, is not a good idea, and eventually will damage your equipment.

Fwiw, I've left my porch system (Integra receiver and disc changer) outside in a cabinet through ten Chicago winters and it still works fine. Now, I wouldn't be so cavalier with high-end gear, and I don't recommend it for others, but there you go.

I don’t think any of that equipment will be damaged in any way. I’ve left some good quality equipment in an I heated storage unit w/ no issues at all; speakers, turntable, electronics. It’s rapid changes in temperature that can be harmful, not slow steady ones within the temperature range your house will experience. 
 

As previously mentioned, by far the most potentially damaging thing you can do is turning on equipment while it’s still very cold.  Any moisture that might be present can get quickly heated by some components like resistors, transformers etc & then condense on a nearby cooler component & then short out. 

I experienced this first hand many years ago when I turned on a TV that was out in the garage on winter & a small fireworks show ensued. Lesson learned on a fortunately a piece of junk. Lesson learned. 
 

I own and rent cottages in one of the most inhospitable temperature-wise places in the US. Temps regularly hit -20F in the winter.

I also own a house (that I occupy) on the property.

I have left lots of equipment out in the barn over the winter. Obviously not my high-end stuff, but lots of CD players, extra preamps, as well as TVs, spare electronics for both the main house, as well as the cottages.

I've also owned boats which had lots of expensive electronic equipment in them (radar, GPS, radios, depthfinders, etc...).

All have been fine over the winters, just let them acclimate before turning them on.

Do NOT put your stuff in a closed closet with a space-heater and leave it unattended. The light-bulb thing (incandescent) is fine (I used to do it in the bilge of my boats, mostly to keep the bilge pumps from feezing up), but that's only going to do so much if the temps REALLY drop.

You state you've been leaving your speakers over-winter there, so no need to worry about the finish on them (cracking veneer, or what-have-you).

I have lots of direct experience with this very subject. Take my word for it, you'll be fine. Manufacturers ship their equipment sealed in plastic bags with silica gel packets as a desiccant. That equipment usually crosses the ocean on a freighter or in the unheated cargo hold of an airplane.

You'll be fine.

As others have said, capacitors may be at risk if frozen. If any components have printed circuit boards, there is also some danger from solder spiders if the humidity and electrostatic charge is just right. Not an issue with point to point wiring.

Recommend that everything be disconnected; remove all power cords and interconnects. Wrapping/sealing is a good idea. When returning, after unwrapping/unsealing allow to acclimate at least 24 hours before reconnecting and repowering. You may also want to deox all the connection and power contacts. 

As a dealer. we received shipments from all over the world, 12 months out of the year. I recall unloading trucks during sleet and snow. These shipments were in transit for days from another part of the country, often spending their nights/evenings stored in unheated trailers. There were also days when the ambient temperatures reached over 100 degrees. A trailer in direct sunlight would have pushed this temperature up considerably -- 130 degrees, plus?

Normally, these items would have plenty of time to adjust to room temperature before put into service. But, I have to admit that when highly anticipated products arrived it was like Christmas morning -- packing material flying everywhere to get to the good stuff inside. Followed moments after by an extreme demo to see what they can do.

Back in college physics we learned about coefficients of expansion, which is to say that different materials expand differently to variations in temperature. So, when our equipment experiences temperature changes, things are tugging and pulling on each other. I can’t say how this would effect things over time. I can say that we operate a part time service business with the goal of keeping good equipment from going into the landfill. I’ve seen gear come in that’s been in non-temperature controlled storage for 40+ years (-15 to 120+ degrees) that seemed to be okay, or just needing minor cleanup, detox, etc.

I’m leaning towards @coralkong ’s impression. Experience and real data are superior to conjecture.

Hello, When you are ready to listen make sure the equipment is acclimated to the living temperature of the house. Like 70 degrees. Once you have done that plug everything in and put in standby to let the capacitors charge up a little. After 24 hours start listening. You are preventing condensation and properly charging the system. I hope this helps. 

Metal oxidation level will be much higher in unheated environment. Plus humidity level will be significantly higher which will negatively affect any contacts and wiring. If you don’t have other options, wrap equipment you intend to leave with several levels of blankets so temperature and humidity level swings will be a little smoother. 

I do appreciate all the feedback.   I have learned a lot here at this forum regarding all aspects of audio.

Especially useful are the responses from people who have done it.

I have left the speakers there for 3 years no problem.

Funny, but it just occurred to me  just before reading the post, lots of gear shipped in container ships.

As my gear has moved up to higher end, it is a significant investment so may start with some of the less expensive stuff.  Problem is you get spoiled.  After hearing N10 through a Yggy it is hard to go back!  But I recently went back to my N100/Gungnir/Senn HD800S setup.  Sounded great!   But when i went back to the N10/Yggy/Focals   sounded much better, if I didn't now know about how upgrades sound I think I might be happy with it..  The N100/ Gungnir can't handle the Utopias, they are too revealing.

I think I will go with shrink wrap and dessicant.  Maybe take my tube amp home one more year.

My cottage is in a little fishing village, so I do have alll year resident neighbors and I hear of little theft in the village, more common in isolated beach houses I think.

Thanks to all and Happy Holidays.

Depends on the location of the house.  There's a difference between Orlando, Florida and Livingston, Montana.

I like the idea from Surfmuz. You can take it to another level by wrapping it in plastic or a garbage bag and putting some desiccant in with the components. You can buy a bunch for under $20. That combined with the process listed above you are set. They can only be used once unless you buy the rechargeable kind. 

Maybe not the same issues, but I used a vacuum cleaner and seal-able bags, sourced from my mother in law, when we put the "stereo" in storage during our big "expedition". I'm pretty sure it got well below freezing in the unit. Everything survived with no damage I could detect. My old cabin Near Breckenridge, CO was broken into several times, BTW, but high transient population...

Don't forget salt air too as a potential issue.  This can be a bigger problem with components that don't have solder mask on the PCB's, or worse, are point to point wired.

I have had a stereo system in my barn for 10 years with no problems.   Yamaha NS 690 speakers & NAD 2400 amp.   Temps would get below freezing a couple times each winter.  And below zero the year we lost electricity.   

I would suggest burying the equipment in the ground at least 9 feet deep.  That will also help against theft.  But don't forget to mark the spot! 

They will be fine. Much to do about nothing. My speakers in my tractor barn out back (South Dakota) look and operate just fine, freezing temps in winter and lovely Black Hills summers. Like tbick I have had the same speakers in the barn for years. I heat it only when out there working in the winter with a Reznor waste oil heater. Old Sf speakers look and sound great running off an old Cyrus Integrated. 

I think the humidity is more damaging than cold. I moved into a stone cottage in rural Limerick, Ireland, and have lost a few pieces of kit. Humidity here averages 75% minimum sometimes reaching into the 90%. Stored for a long time the power caps discharge completely and then draw huge amounts of current at switch on. When I moved country I sold a lot of stuff including my variac which I used to slowly bring equipment up to voltage. 

In future I will do as @puptent suggested, vacuum bag the components but only after leaving them overnight with a dehumidifier running.

I would like to see Richard Vandersteen's answer on this one.  He monitors the Owners Forum.  Why not join and ask there?  Go to the website and click Forum.

I don't get the worry about caps. AC units that are outside all winter have caps and they're fine.

Just intuitively, I'd be more concerned about speaker drivers freezing.

There are a lot of temperature control products for aquariums/terrariums.  I'd look into that.  

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