The camper has been on the storage lot since the first week of November. It froze hard again last night, the lot is forty minutes each way down a road that is worse than the forecast admits, and it is Sunday. You think about driving out to look at it. You do not drive out to look at it.
Which is a shame in one narrow sense, because there are just two things you would learn out there: whether it is getting too cold, and whether something is still running that should not be. Everybody thinks of the first. The second is what quietly costs people money all winter, and it is much the more interesting of the two.
The cold question is the easy one
It is mostly answered in the freeze protection guide, so the short version will do. The number that matters is the wet bay rather than the cabin, because the plumbing crosses freezing hours before the living area gets near it, and the alert wants to sit well above freezing so the warning arrives while the water is still liquid.
What changes in storage is not the rig, it is the sensor. Coin cells lose capacity in the cold, so a puck that has reported faithfully since June can stop in the first hard freeze, and from home a dead sensor and a rig that is fine look identical. Alert on battery level, not only on temperature, or the freeze sensor fails silently in precisely the weather it was bought for. The related trap: cheap sensors are indoor sensors, a wet bay in February is far closer to outdoors than in, and a sealed enclosure like the RuuviTag’s earns its price out there in a way it never does indoors.
Is anything still drawing power?
A stored camper on shore power should be dull. The converter trickles into the batteries, a tank heater might come on and off, and plenty of rigs sit at very nearly nothing. What that number is does not matter in the slightest. What matters is that you know what your own normal looks like, because from then on anything else is a question worth asking.
Learn the baseline before you set anything. Watch the draw for a week, then put the threshold either side of what you observed. A rule written against a number you have seen beats one written against a number you guessed, and it is the difference between hearing about a real problem in February and being told all winter that your converter is doing its job.
A draw above that baseline is nearly always one of four ordinary things. The water heater was left on, its element cycling since November to keep a tank nobody is using hot. A space heater is plugged in, quite possibly the one you carried out there yourself before the first frost. The fridge is still running: doors shut, nothing in it, chilling an empty box for four months. Or the furnace is running far more than the weather explains, which usually means a vent is open, a window is cracked, or a door did not latch the day you left.
Then there is the case that justifies the whole setup, which is the draw dropping to zero. Zero means shore power is gone, and in January that matters more than any temperature reading, because temperature tells you the rig got cold while power tells you the heat stopped. Those two can be most of a day apart on a stored camper, since a closed insulated box gives up its heat slowly, and every one of those hours is one somebody could have used to get out there.
The setup, in order of what it earns you
- Shore power. The leading indicator for everything else here. An EMS that broadcasts, like the Hughes Power Watchdog, gives you voltage and draw rather than only on or off.
- Wet bay temperature. The early warning for the plumbing, and the reading that crosses the line first.
- Cabin temperature. The reference. It says whether the furnace is keeping up and gives the wet bay number some context.
- Propane level. If you are heating with it, a Mopeka means an empty tank is something you get told about rather than work out in the spring.
A leak sensor on the wet bay floor makes a reasonable fifth, provided you are clear what it is for. It will not catch a line splitting, because nothing leaks while the water is ice. It catches the thaw, hours ahead of anyone finding out the usual way.
Getting a signal out of a storage lot
None of this reaches you if the rig has no internet, and connectivity is the genuinely hard part of watching a stored camper, because storage lots rarely have Wi-Fi you can join. The honest options are these, and none of them are free.
Stored at home you are nearly done: house Wi-Fi often reaches the driveway, and where it very nearly reaches, an outdoor access point fixes it permanently for less than one bad repair. Off site, most people end up on a cheap data plan with a hotspot in the rig, which works because monitoring traffic is tiny; you are sending numbers, not video. Cellular in the hub itself is planned and will be billed per hub, because each hub carries its own SIM. It is not available yet, and we would rather write that down plainly than let you plan a winter around it.
There is a fourth answer nobody advertises: run the sensors with no connection at all, accept that you are logging rather than alerting, and read the history when you next visit. Worth less than an alert, worth a great deal more than nothing. You come back to find the draw ran double through the second week of January, which tells you something was open.
One thing to say plainly, and it matters more in storage than anywhere else on this site: monitoring is not winterising. If the rig is sitting through a real winter, blow the lines out and use antifreeze. A temperature alert is for the cold snap you did not plan for, not a substitute for draining a system you are walking away from. Sensors tell you what is happening out there. Antifreeze is the thing that stops it.
What the whole arrangement buys you, on that Sunday in January, is permission not to go. The draw is where it has sat since November, the wet bay is at 41 degrees, the propane is at a third, and none of that needed anybody in a truck. Whatever the camper is up to on that lot, it is not doing it in secret.
