Low powered interior heater for the winter

[MikeWilliams]

This isn't for a Jensen, but could be. I have a car which is kept outside during the winter, with the battery on full time charge. Obviously, with cold and damp the interior has a lot of condensation. So, could I plug a low powered heater into the cigar lighter socket and run it 24/7, just to lift the temperature a couple of degrees and keep it dryer? Bear in mind the battery is being charged on "maintenance" setting all the time? I am thinking of maybe a 50w heater.

Mike

[kees]

It seems to me that it will be highly unlikely that 50W will be sufficient. It is like having a head light bulb on inside all the time.
Why not have a heater connected up to the mains? There are plenty low cost ones about which have a thermostat so you can adjust to the required temperature.

[MikeWilliams]

One reason for not wanting a mains heater is the need to keep a window open for the cable. I hoped 50w 24/7 would do a little. I guess better still would be a dehumidifier, but can't find one for 12v.

Mike

[kees]

You do not really need 12V apparatus. You can always get a converter 12V DC to 240V AC. They are cheap enough.
However the main limit is the capacity of the charger and the wiring of the cigar lighter socket. I would imagine that about 5A (also about the max of most chargers) would be safe enough which means that 60W (5x12) is available for a dehumidifier or heating system.

[MikeWilliams]

Thanks Kees. Tubular greenhouse heaters seem to be 45w or 80w, so I hope it would do something. I know - the alternative is to actually use the car, but that's not possible just now!

Mike

[Chris_R]

Can you not keep it in an outdoor Carcoon?

[MikeWilliams]

Yes, I could Chris, though it would get in the way of other cars a bit and cost several more than the car is worth - its not a Jensen. I guess long term I need to rationalise cars!

Mike

[Martin R]

The carcoon works I believe as it's theory is based on airflow over and through the car. Leaving the windows slightly open allows air to circulate through.
I wonder if you could hook up a small fan, near open dash vents (assuming the car has them) which might be sufficient to make the air flow the length of the car to exhaust through the rear vents (assuming it has them).
A small USB computer type fan uses very little power and might be operated off a USB "charging bank" thingy. It might last several days between recharges too.
Worth a try?

[johnw]

I checked a 1970s classic car we left out, original rubber door seals, 35,000 miles, outside for the last 10 days in this bad weather, Swiss rain and snow around or below freezing at night, in the open no car cover, and we had put a special 9.99 euro bag of Silica Gell, this car damp remover solution inside. It is in a cloth bag, it has an indicator which turns from blue to pink. Inside the car, just checked yesterday, the inside of the screen and windows were totally dry as promised, despite slush on the outside, Daytime temp was 2 degrees C today. The indicator has gone from blue (dry) to white, I expect it to transition to pink over the next few days. You then microwave the bag for 6 minutes and reuse. So yesterday I cleaned the snow and slush off and fitted a waterproof plastic car cover, and put 2 more bags on the inside for overkill.

I have an old van that gets left out in all weather, occasionally it can get really iced up outside and freezing damp inside. A 1.5KW mains powered fan heater on the inside for an hour before use does wonders. The snow and ice brushes off, and there is no freezing breath on the inside to contend with.

I don't leave a battery or electrics connected to a vehicle that is not regularly used, after I had a modern car catch fire.
I had a VW spontaneously combust, after what appears to be a short circuit in the indicator stalk area. Shouldn't be possible I know. 15 year old backup car, not messed with electrically, I had recently tested the gears on the drive, then parked it up. I normally disconnect batteries, but didn't. A week later the instruments and interior round the steering column had turned into a melted blob, steering wheel burnt and melted, windscreen cracked by heat, all windows smoke tinted, flames had reached the headlining and when that set on fire it had some self extinguishing content that put the fire out. No life would have survived, and I had to leave the visually undamaged cloth upholstery undercover outside for 2 years after hosing it down before it stopped smelling. The battery discharged so quickly it was finished and wouldn't recharge. It could have burnt a car next to it or the house had it not self extinguished.

Batteries are now removed and fully charged, with a cheap intelligent charger from Lidl or Aldi, left on for a couple of days, then left disconnected for 3 months or so, until the voltage drops to 12.4 then another couple of days.
I do think the heat from a 50w car headlight would make a difference to the inside. However I wouldn't do it. I disconnect all car batteries when cars are not in use, and charge off the car.