Running a dehumidifier off of a 12V battery (thinking of)

[AstonHill]

I use the cheap non-reusable silica things in the caravan over winter - keeps the thing reasonably dry so the cushions don't get stinky and start rotting.
For drying out a flooded house you're looking at days not hours.

But its OK for drying out a caravan if you leave the thing in there all the time?
How long dose it last before you have to recharge/ dry carterage?

Cheap domestic gennies aren't rated for 100% duty- in that world you are looking at proper silent diesel sets.

I always wonder why they list generators with maximum run time on them of say 4-5 hours

 

[Mottie]

For drying out a flooded house you're looking at days not hours.

About 15 years ago, the old lady that lived next door to us passed away. While her house was unoccupied we had snow and very cold weather. When it thawed, a pipe burst in the loft and flooded the house (it was running for ages until Mrs Mottie heard it one evening). I gained entry and turned the water off but the whole of the upstairs and downstairs ceilings had fallen down and everything was saturated. Carpets, curtains, floorboards, walls etc. Her son sold the house to a builder who completely gutted and renovated it. He had humidifiers in there and I seem to remember they were running for weeks, not days.

 

[Mottie]

I use the cheap non-reusable silica things in the caravan over winter -

A lady I worked with had a caravan. At the end of the season when they weren’t allowed in them for a couple of months, all the owners used to go down to them to carry out what they called 'salting'. They just put piles of salt on plates/dishes and left them to absorb the moisture when it was unoccupied.

 

[flameport]

But how long would the generator need to run for?

As long as you want to run the dehumidifier for.

so is electric used to do this?

It is in that particular one. Demonstrated in the video you didn't watch.

 

[Ivor Windybottom]

Dehumidifying may be a bad idea in newbuild, as it could dry the concrete and mortar out. It needs to stay damp as long as possible to react and develop its strength.

Also plaster may shrink and crack if force-dried.

Much better to keep the place damp, it will naturally dry out at a reasonable pace.

 

[AstonHill]

Dehumidifying may be a bad idea in newbuild, as it could dry the concrete and mortar out. It needs to stay damp as long as possible to react and develop its strength.

Also plaster may shrink and crack if force-dried.

Much better to keep the place damp, it will naturally dry out at a reasonable pace.

well i ordered that item from ebay, will give it a go when it arrives, hope its better then salt!

Thanks

 

[robinbanks]

They are low capacity and only last a few 100 charge/discharge cycles at best.

Bit of clarification there; a lead acid battery will be quickly destroyed by deep discharge/recharge cycles but floating them between 80% and 100% SoC will see them last for many thousands of cycles. This of course means you have to have 5 times more battery capacity than the capacity you need, because you can only realistically use a fifth of the capacity of each battery

 

[AstonHill]

Bit of clarification there; a lead acid battery will be quickly destroyed by deep discharge/recharge cycles but floating them between 80% and 100% SoC will see them last for many thousands of cycles. This of course means you have to have 5 times more battery capacity than the capacity you need, because you can only realistically use a fifth of the capacity of each battery

So what causes them to fail? How dose the led on the plates end up in the trip tray? Dose it bond with the saulfer stuck on the plates or something?

 

[Ivor Windybottom]

I've got the ebay "rechargeable" dehumidifiers now. They're actually very well made, a total bargain for £18 delivered.

Both indicators were slightly dark yellow on arrival, I gave them both a blow on the base for an hour each, which seemed to lighten the colour a bit. I have now deployed them to the shower room. Time will tell, but I hope that they will reduce the condensation that can occasionally build up in there.

The shoe dryer is a weird bonus! I'll probably use it the next time I've washed my trainers.

 

[AstonHill]

I've got the ebay "rechargeable" dehumidifiers now. They're actually very well made, a total bargain for £18 delivered.

Both indicators were slightly dark yellow on arrival, I gave them both a blow on the base for an hour each, which seemed to lighten the colour a bit. I have now deployed them to the shower room. Time will tell, but I hope that they will reduce the condensation that can occasionally build up in there.

The shoe dryer is a weird bonus! I'll probably use it the next time I've washed my trainers.

The sample beads in the top of the cartarage are of a different colour to that of the rest of the cartarage

 

[Ivor Windybottom]

Errrr.... yes they are. As shown in Big Clive's video. They're an indicator, to show the state of the rest that you can't see so there would be no point in colouring them.

I would add to my previous review to say that they are darkening so are absorbing moisture. But they're nothing like as good as a dehumidifer, mostly because there's no fan so they're dependent upon the damp air happening to find its way in, which it mostly won't. I had condensation on the window right behind one.

 

[AstonHill]

i wonder how much water a cartrage can hold though

 

[Why Not Indeed]

Weigh it. Use it. Weigh it again. Difference is how much it absorbed.

 

[AstonHill]

Weigh it. Use it. Weigh it again. Difference is how much it absorbed.

Great idea! will do so and post back (if i find a battery for my scales LOL)

 

[ericmark]

We used some thing like this they clearly worked as the water arrived in the bottom, but the best dehumidifier had to be single glazed windows with a small built in tray on the bottom of the metal frames and a hole to the outside, you could see the water running down the windows, and when the temperature dropped got some lovely frozen patterns, as a child was told painted by jack frost.

The biggest problem I had with damp was living in a caravan, the problem was we used gas for heating with no flue. Burn a hydrocarbon and the hydrogen combines with oxygen in the air to make water. So putting on the gas fire to dry the caravan simply did not work. Cure was to get electric hook up, and use a fan heater, latter caravans had a gas heater with a flue.

So the main thing is to stop what ever is making the place damp rather than try to remove it. Stop breathing as your body burns hydrocarbons, but that is not really the healthy option. But it is more down to ventilation than removing water.