When I initially built our bus conversion, I tried to save where I could. This lead to numerous times I ended up buying items twice, can I get a witness? I initially went with a cheap Chinese no name 24-12v converter.
Anyway, I was noticing my diesel air heater was giving me some white smoke during full fuel situations. So I did some thinking, it could be that there is some soot in the burn chamber (still could be the case) but also could it not be from not getting enough air? I noticed under full load it was only getting 11.3v or less with the glow plug on. I measured my 24-12v converter and it was non adjustable and outputting 12.3v Not surprising that by the time it went through all the wires, connections, fuse panels, etc I'd get a volt of drop. So I'm thinking, if I can get more volts, I'll get more fan speed, more air, less smoke.
I bit the bullet and bought a Victron Orion 24-12v converter last week and installed it yesterday. I set the voltage to around 13.8, I figure most things work better with traditional alternator output voltage. So far no real difference in the diesel performance, smoking hasn't been an issue with the warmer temps, but we're getting into -20f range here soon, so we'll see.
I also had a 12v to USB converter die on me this last fall, it powered my raspberry pi with a LCD screen for my Victron monitor, I suspect I was pushing it to it's limit. I wonder if the lower volts was harming that. I'm also hoping the extra volts will help my 21' awning roll up better.
So curious what everyone's take is on what actual voltage do you run your 12v house voltage at?
I've run across this problem a few times, most recently when installing a bank of four converters to run my 12v headlights on a 24v bus.
You are correct - nearly all automotive appliances and devices intended for use on a 12v system are configured for optimal performance at about 13.8v, which is typical for an auto alternator when the vehicle is in operation. That's the voltage I've been using for my converters on the headlights and finally have good light output.
On most S&S (sticks and staples) RVs, they are also set up for use when the converter or charger is running which is somewhere between 13.2v and about 14.0v. A fully charged 12v battery will likely measure about 12.7, and by the time it's down to 12.0v it's usually down to about 50% SOC (state of charge) and in need of recharge.
I'd stick with the 13.8v converters, and make sure that the one you use can supply more than the anticipated current draw on them. I usually go with double the needed capacity to ensure that they run cooler, on the thought that cooler operation results in longer life. Push converters towards their max output and things start to fail sooner.
This one is 70 amps.. nearly double of what my last one was, I bet that helps too.
In addition to bigger, I also like redundancy. My headlights are power from the factory with 4 separate circuits - one for each side hi beam and one for each side lo beam. I kept that redundancy and installed four separate 24v-to-13.8v converters so at most I'd lose one of the four and not all four. These replaced the OEM resistor bank which was failing.
I never like to put all my eggs in one basket, or in this case in one converter.
My inverter is 24 volts so my battery bank is 24 volts of course. Some stuff I can't get in 24 volts so I tap the battery bank to get 12 volts with a Vanner Equalizer keeping the two halves of the battery bank in balance.
My 12 volts is half of whatever the 24 volt battery bank is sitting at. I am usually a bit under 13 volts unless the charger is providing power when it will be closer to 13.5 volts.
Modern alternators have a sense wire that goes to the battery. That way they don't measure the voltage from the alternator charge which is always a little higher than at the battery due to the resistance in the wire, and then you also have the resistance in the sense wire. It isn't that much but a couple tenths of a volt can make a big difference.
Electrical/electronic components that are made to hold up to 12v are not going to fail on 24v, although that's not true with lights and less certain with motors. It always depends on how well they can get rid of the extra heat. So when it's cold out I can't see there being much of a problem running that Webasto on 24v even when it is supposed to take 12v.
I remember when we did 6v to 12v conversions and all we did was change out the incandescent bulbs. Starter and wiper motors did fine.
Jim
QuoteElectrical/electronic components that are made to hold up to 12v are not going to fail on 24v, although that's not true with lights and less certain with motors.
So true, this summer I was working on my old onan generator. I was experimenting with using chassis ground and part of my 24v battery bank to start it. Well wouldn't ya know it, once time I connected it to the 24v side. That thing startup so quick I was amazed! I seriously contemplated on leaving it on 24v.
So far so good the diesel air heater is working better than ever. Only hit 12.5v during startup this morning.
If i remember right, 12.2 is at 50% charge and 12.0 is at 25% charge.....for optimum battery life don't let them get below 50%. This is for lead/acid batteries, don't know what it is for other types.
Right, this is about a step down converter and what voltage it was putting out. I have a 24v battery bank, so my 12v side is consistent no matter what. Before I couldn't control it, it was always 12.3 Now I can set it anywhere from 10 to 15v , I chose 13.8 for now.
My Yaesu ham radio gear runs on 12v, but of course they don't recommend that you actually use 12v. The recommended voltage is 13.6v - 13.8v, which is what I have used in the bus for the 12v systems as well.
Did you say -20F!!! What kind of diesel heater is that?
Quote from: fortyniner on February 05, 2021, 05:08:23 PM
Did you say -20F!!! What kind of diesel heater is that?
You must not be from the upper midwest. We're expected similar weather here in Wisconsin this weekend. Not quite as cold, but still down around -10F. I spent about 3 hours out in 0F this morning clearing snow. It wasn't all that bad being dressed appropriately.
We live in Florida & just gave best offers on two Chinese diesel air heaters on eBay for when the bus is in the cold. We'll see...
Just curious what the story is for those suffering below freezing conditions. How many buses are being used or they all winterized and parked?
What experience can be shared by those who have ventured out in freezing conditions and gone boondocking? What are the key issues to ensure a happy winter bookdock expedition?
With all the snow up in the Sierras I may be simply stupid but thinking from this warm room that it might be pretty exciting to take the bus up the hill for a few days.
People working on heaters for -20* and I am thinking about checking my dash air to see what is wrong you guys are tough
Quote from: windtrader on February 05, 2021, 10:27:32 PM
Just curious what the story is for those suffering below freezing conditions. How many buses are being used or they all winterized and parked?
What experience can be shared by those who have ventured out in freezing conditions and gone boondocking? What are the key issues to ensure a happy winter bookdock expedition?
With all the snow up in the Sierras I may be simply stupid but thinking from this warm room that it might be pretty exciting to take the bus up the hill for a few days.
Suffering? Right now I'm toasty warm inside while the temps outside try and climb towards 0F. I wouldn't say that I go out in these temps on purpose, but I certainly don't avoid it if there is something that needs to be done. Good thing we have a period of sub-zero weather every year too, or we'd be inundated with bugs, beetles, and other creepy crawlies all summer. Nature's way of doing pest control.
We haven't yet used our bus intentionally in sub-zero weather for trips, but I have had it out for an occasional short road trip. Also have used experimented with the heating systems on the house side to see how capable they are. The OTR system doesn't have a problem keeping the inside warm once the engine warms, and between the gas furnace and the electric heaters the inside stays comfortable in sub-zero temps. Takes a bit to get it warmed up from scratch though.
Once we get a better way to keep the wet bay warm while dry camping we're going to try doing some more camping into early winter and early spring, trying to push our season longer by a few months. The one thing we will avoid though is putting the bus on salt-covered roads, but even with that it should be possible to length our season by a few months once the wet bay can reliably kept warm so we can still brush and flush.
Even with our current use of the bus, there are times when we are dealing with temps below freezing. I used the bus last spring to live in while I was going through truck driver training in Marinette WI for a job. Even in May, night time temps were dropping to the low 20s and I had no problem staying comfortable with just a 15-amp hookup. Thankfully we have a heavy curtain to keep the cold in the cab area up front so the rest of the bus can stay comfy.
Assuming that the bus side of life is set and that the bus will operate/drive in cold temps, there is not much involved in keeping the house side functional in cold weather. It all revolves around keeping the plumbing from freezing and depending on how your bus is designed it could be easy or impossible. I'm working on tweaking our wet-bay with some insulation and additional heating to take care of my biggest worry, and then I'll just have one issue to deal with. For whatever reason the Custom Coach people ran the water lines to my shower between the outer plywood wall of the bathroom and the windows, and I'm working to come up with a plan to either keep them warm, shut them off and drain between uses, or re-route them. Then we should be good to go for winter use without as many worries.
-30 f is the coldest I have had the pleasure of overnighting in .
HAD to do it on 2 different occasions and never again
1st time the water line going to the water pump froze in the lower water bay . the inside of the coach was warnish 65 f but the front windshield was covered in frost on the inside . after I started the engine it took a while to get the frost off the windshield even with the diesel boiler on heating the engine and a scraper .
both times we were on our way back from Florida to home
brrrrrrrrrrrrrrr
sorry for the drift
dave
@Dave
That's the very situation we'd hate to see upon a late leave from Alaska to get back to FL for the winter.
Sounds like you left FL early to go back to CA for summer?
An old timer in AK told us the only way to stay comfy in an RV in AK in wintertime was to garage it at 30F & it might be ok.
10-4 on brrrrrrrrrrrrrrr!
both times the -32 f we had no choice but drive through it as I had to get back to work .
I have snowmobiled in much colder weather
there is nothing like snowmobiling at - 45 at 100 mph !!
and the sled loves it at that temp. but good thing the sun was out with no clouds cuz it felt warmer
ps if I had to camp in the coach in cold temps I would install a small boat wood stove
dave
Even bears are smart enough not to go out in those temperatures,we spent 1 night in -20* in our bus never again for me
same thing we were in Timmins Ontario and had no other way of getting home . some of the sledders rented trucks to get back to where they parked there trucks to get home . all truck rentals were gone
nothing better then a northern sleddin trip from small town to small town cuz the trails that far north are amazing and if you are dressed for it so you do not get frost bite
dave
dave
Snow is a lot better than ice like Tulsa would have
ya black ice can make for a bad day
dave
Now we know where "sledhead" comes from.
-45 @ 100 mph - geese!
and people think bus nuts are NUTS
dave
My bus was outfitted for cold. It has all the stuff like block heater, electric and connected to diesel Webasto, piping is wrapped in that heater wire, bays are heated via Webasto, etc. Maybe it is asking too much to camp fully off-grid in the cold. Some of the freeze protection requires AC and I have no idea how many watts it would take to keep the freeze away.
I'll have to go look to see how many pipes are exposed outside of bays.
Then there is the road conditions as mentioned "black ice" or anything making the bus have less than 100% grip seems pretty foolish to voluntarily drive in.
Maybe do an overnight or two at lower elevations like at snowline or slightly above to see how it goes. The Yosemite valley is awesome in winter wit some snow on the ground.
IMHO I think the most important thing to have to ward the cold off is redundant heat in multiple forms - not just in our buses but in our homes too!
Having a get away in Alaska now brings the cold more to mind. We live in FL but are from NJ so we know cold some.
An old timer that delivers various heating fuels in Tok AK told us when wintering in a place like that to have at least three of the four general sources of heating options.
ie: wood, propane, fuel oil, & electric.
In the bus we have great otr heat, propane, electric, soon to be diesel air heat, & already got a small wood burner but haven't yet brought myself around to doing the architectural remodel to install it. Also built into the bus is utility redundance. Two LP furnaces, several sources of electric heat, electric water heater, LP water heater, tandem demand water pumps, two refrigerator/freezers (110vac, 12vdc, & propane), main genny & small back up genny, two block heaters 1 on the block & 1 in the heater loop. Heated & insulated bottom compartments. We carry some spare parts & after 42 year of same bus ownership we like to think we have it down to an art. BUT we learn until we expire.
Through the years we've had the ole' girl in some pretty precarious places & situations. And yes even a tortoise with an IL671 has been to the top of the majority of National Parks in all seasons.
We do carry chains...
Winter camping needs lots of heat to be happy.
If hardcore is your goal, remember that propane won't come out of the tank at all below -44 degrees, and is not running right below -35 on a high draw appliance...
Your batteries will be struggling, if they are vented outside.
Pretty much plan to have an engine running, cuz loss of heat or power is a life support issue, not just an inconvenience like in the summer.
Block heater on the big engine, if it is turned off.
And enough winter clothes to survive epic failure of the coach systems.
What's the anti-freeze strength in the generator...? And is there a way to heat it to aid in starting?
Happy coaching!
Buswarrior
Dan looks like you have it covered
when I had to return home and it was -32 out I was worried about turning off the 6v92 ta to sleep for 5 hrs . when I woke up 1st thing I did was turn on the elect. block heater ( 1500 watt) when I was making coffee and a muffin and washing the sleep out of my eyes . 15 min. later I fired up the engine and all went fine . but the genny and the diesel boiler was on all night so I do not think the engine had enough time to get to cold . but it was really windy all night and cooooold . My wife would not let me run the engine while we slept
if I was to put in a small boat style wood stove it would only be for extended camping or in a emergency and I would make a small insulated panel with aluminum on both sides to install by way of opening a window slide it in and have it fit tight . this way I would never have to deal with the chimney going down the road . but you could use skids cut up really small as fire wood and they are everywhere .
got to love winter
dave