Webasto 24v to 12v converter

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Webasto 24v to 12v converter

Postby bobby-gg » 10 Jul 2018, 12:47

I've had my webasto installed in my van for just coming up to a year, and although it's summer on the recommendation of a Facebook post I thought I'd run it today just to make sure it works

Well, it doesn't

Mines a 24v one and I used a 12v to 24v 12a converter that I bought from amazon, and I'm getting a steady 24v out from it until I operate the heater, and the voltage drops down to 5v, the controller powers off, then when the load has come off the controller powers up again

I thinking that the converter has failed, its fully enclosed and I haven't tried to get into it yet, but thought it'd ask for reliable converters that others have used successfully and I'll try and send this one back

Rob
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Re: Webasto 24v to 12v converter

Postby Oldiebut goodie » 10 Jul 2018, 13:34

Post a pic/link of what converter you are attempting to use. Also what model of heater. That is normal with a lot of step-up converters - basically they are cr*p. I sell 24v heaters with 12-24v converters all the time. A decent converter only costs £4-5 for an Air Top 2000 and £10ish for an Air Top 3500/5000.
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Re: Webasto 24v to 12v converter

Postby bobby-gg » 10 Jul 2018, 16:19

Oldiebut goodie wrote:Post a pic/link of what converter you are attempting to use. Also what model of heater. That is normal with a lot of step-up converters - basically they are cr*p. I sell 24v heaters with 12-24v converters all the time. A decent converter only costs £4-5 for an Air Top 2000 and £10ish for an Air Top 3500/5000.


I'm running an airtop st2000

I'm using this converter from amazon, it's worked fine all winter, the last time I used the heater would of for a weekend in February, so it was up to job, but looks like it's could have now failed

https://www.amazon.co.uk/gp/product/B01 ... UTF8&psc=1

Rob
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Re: Webasto 24v to 12v converter

Postby Oldiebut goodie » 10 Jul 2018, 16:50

A lot of ones like that cannot cope with the start up currents, even 300w ones.
Use these - I have been using them for years:
Use one of these https://www.ebay.co.uk/itm/DC-DC-10-32V-to-12-35V-12V-24V-6A-Adjustable-Boost-Step-Up-Converter-Module/232812880591?hash=item3634baa2cf:g:I60AAOSwi0RbJ89v for an Air Top 2000.
You can get an inrush of in excess of 15A on a 2000 which these can cope with unlike those potted ones.
Don't be tempted by these 250w ones either https://www.ebay.co.uk/itm/Brand-New-Step-Up-Power-Converter-Regulator-DC-12V-TO-24V-12A-250W/201735955726?epid=569343232&hash=item2ef866650e:g:JxQAAOSwopRYeUel they will not work with a 2000 either.

or https://www.ebay.co.uk/itm/DC-10V-60V-to-12V-24V-36V-48V-80V-10A-Converter-Step-up-600W-Module-Power-Supply/161491267682?hash=item2599a13062:g:CPkAAOSw0vBUbUTX for an Air Top 3500/5000 - you can use these for the 2000 also of course.

On both of them check the soldering carefully before use especially the terminal pins, quality control is not that good - that applies whether you buy them from the UK or China. Just mount them in a plastic project box. Set them to 25 - 26v. Have the converter next to the battery rather than at the end of a 12v line as there will be less voltage drop with the higher voltage transmission.
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Re: Webasto 24v to 12v converter

Postby bobby-gg » 10 Jul 2018, 17:15

Thanks, ordered the 600w one

I've already got the existing one mounted in a box, under the seat next to the leisure battery, I'd followed someone else's install where you'd recommended how to do it, but I'm sure the links were dead for the converter and that's how I ended up grabbing one from amazon

Anyway, once I've got this one working I'll see if I can return the amazon one

Thanks again for your help
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Re: Webasto 24v to 12v converter

Postby bobby-gg » 07 Aug 2018, 07:54

Oldiebut goodie wrote:A lot of ones like that cannot cope with the start up currents, even 300w ones.
Use these - I have been using them for years:
Use one of these https://www.ebay.co.uk/itm/DC-DC-10-32V-to-12-35V-12V-24V-6A-Adjustable-Boost-Step-Up-Converter-Module/232812880591?hash=item3634baa2cf:g:I60AAOSwi0RbJ89v for an Air Top 2000.
You can get an inrush of in excess of 15A on a 2000 which these can cope with unlike those potted ones.
Don't be tempted by these 250w ones either https://www.ebay.co.uk/itm/Brand-New-Step-Up-Power-Converter-Regulator-DC-12V-TO-24V-12A-250W/201735955726?epid=569343232&hash=item2ef866650e:g:JxQAAOSwopRYeUel they will not work with a 2000 either.

or https://www.ebay.co.uk/itm/DC-10V-60V-to-12V-24V-36V-48V-80V-10A-Converter-Step-up-600W-Module-Power-Supply/161491267682?hash=item2599a13062:g:CPkAAOSw0vBUbUTX for an Air Top 3500/5000 - you can use these for the 2000 also of course.

On both of them check the soldering carefully before use especially the terminal pins, quality control is not that good - that applies whether you buy them from the UK or China. Just mount them in a plastic project box. Set them to 25 - 26v. Have the converter next to the battery rather than at the end of a 12v line as there will be less voltage drop with the higher voltage transmission.



Just some feedback OBG

The converter arrived whilst I was away with the van but I fitted it over a week ago and once set it its been working fine, I've tested it about 4 times now and it's worked every time

Thank you for the advice.

Just got to sort out the thermostat and perhaps a remote control for it now

Rob
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