WEBASTO AMP REQUIREMENTS

[Stormcloud]

I have a Webasto DBW2020 installed in the bus for coach heat when parked/boondocking. I recently installed a Bogart Trimetric monitor on the house bank system, and am getting familiar with its capabilities, one of which is ampere draw from the bank.

I noticed that the Webasto and its circulating pump pulls a lot of power from the 24 volt house bank.... a LOT of power....like 25ish amps when operating.
When the Webasto is off (circulating pump only) it is around 10 amps, so the Webasto is pulling about 15 amps at 24 volts.

The Webasto seems to operate correctly, other than it is a bit noisy. I have a 'spare' head unit for it, and the load appears similar....
so I either have 2 units with similar problems, or I should be increasing gthe size of the battery bank.

Anyone have experience with the Webastos? Is this normal?

Thanks!

Mark

[Nick Badame Refrig/ACC]

Hi Mark,

The normal power draw for a 2020 is 120 watts without the pumps.

Devide that by 24v and you should be right around 5 amps. Some of the bigger circulator pumps

draw as much as 130 to 140 watts. Then add any blower fans to that too..

You may have a burner head with a faulty motor causing excess amp draw. Check it out with an

amp meter.

Good Luck
Nick-

[Stormcloud]

Thanks, Nick. I should be able to check this tomorrow, now that I know what to look for.

Regards.

Mark

[lostagain]

Mark, fwiw, all the years I drove the hockey team's D3 with the DBW2020, I used it a lot: for up to an hour to preheat the Series 60, and I would usually turn it on after the second period so I would have a warm bus at the end of the game. I don't know the amp draw figures, but it was never a problem with the 2 8Ds.

Also, do you have the manual for it? If not I can forward mine to you, I think it is a PDF.

Take care,

JC

[Stormcloud]

Hi, JC.

I have downloaded the manuals from TechWebasto. I found where the different pumps have different wattages, but could not find the requirements of the heater. I can hook my ammeter to the device and check.

I sure like the heater for boondocking. At -25F in Pierre, SD two winters ago, we were as warm as toast in the coach. I have the loop in place now for engine pre-heat, and still need to plumb in the waterheater for hot water.

Thanks for the offer. Hope all is well with you and yours!


Mark

[Nick Badame Refrig/ACC]

Hi Mark,

Here is a PDF of the service manual for the 2020, 2010.

Page 20 bwill show the wattage draw.

http://www.techwebasto.com/heater_main/LIT699745A.pdf

Nick-