We had a rather cool day today (mid-50s) so I thought it was time to test the Webasto to see if it would start. The instructions left by the previous owner consist of:
1- Pull switch to turn on.
2- Control fan speed with rotating knob.
3- Control temp with thermostat.
Not much to go on there. I pulled switch. The green light came on indicating something was going on. Only nothing really was.
Before digging in without knowledge, I thought I'd ask and see if someone could point me in the right direction.
The previous owner did leave me with a fuel filter and a replacement nozzle. Seems like he thought those would be needed. Beyond that I have no clue. I did find a manual in my stack of paperwork, but it was not much help either.
Richard
The best answer can be obtained from Lloyd DeGerald. He travels the country to all of the RV shows and repairs these. You can reach him by phone. He is on EST most of the time. Check out his website. http://lloyddegerald.com/blog-1/ (http://lloyddegerald.com/blog-1/) or call him at 501 258 8426. Tell him Gary sent you. I just checked his scheduile and he is home now in Paron, AR.
The Webasto manual should have all the troubleshooting procedures. Maybe it's a fuse.
--Geoff
Webasto is very generous with their manuals, all available online.
Extensive explanations, parts diagrams, trouble shooting.
A great unit, simply needs to be understood and maintained properly.
Skimp on anything, you pay the price in dysfunction.
Your system is more than just the "webasto" It sounds like there are all manner of other bits and pieces.
The Webasto is the coolant boiler that warms the liquid that circulates to your various other devices that distribute that heat.
happy coaching!
buswarrior
There are several things that could be the culprit, so at this point you have 2 choices. 1. What Gary said, Call Lloyd. 2. What Geoff & BW said, study the manual & troubleshoot. Then when you narrow it down to a particular part and or have a specific question that will make it easier to answer. When you turn it on does the webasto unit itself make any noises ? If so, what noise?
.
I have rebuilt several 2010's and learned an interesting bit about the bearings. The fan shaft uses an ever popular 608Z bearing. But, 608Z bearings come with MANY different types of lubricant inside of the them. I rebuilt one with OEM bearings and had no issues. I rebuilt another with 608Z bearings from online ($1 a piece) and it bench ran perfectly, but when it was COLD outside, the unit didn't run properly. Turns out the grease in the bearings was too thick (combined with the cold fuel going through the fuel pump) and 2010's motor ran too slow for proper ignition. Oil lubricated 608 bearings solved the issue, but they aren't $1 a piece.
They are amazing pieces of engineering and are usually under maintained, but when you go through and baseline an older unit, it'll run as well as any new unit.
Motor RPM is key. Too little, and it'll never run right. The items that will bring down RPM; bad motor, bad or incorrect bearings, fuel pump.
This question might be really a beginner's one, but I still can't figure out the fan for my Webasto.
The Webasto is connected to the bus's cooling system. The coolant runs through the same hoses/pipes as the OTR HVAC systm.
When I fire up the Webasto, am I expecting the bus's air circulating fan to turn on, or is there a separate fan that will run with just the Webasto? If there is a separate fan, then is there a separate air handling system (vents) or will the Webasto fan push air through the bus's vents?
I'm assuming that there is a separate fan for the Webasto, as otherwise my batteries could never power the fans for more than a short while.
Or...Maybe I should ask if it's even possible to heat the bus using the Webasto when not on shore power or running the generator?
Don't think I've found all the components to the Webasto system yet. Hoping to get a little help knowing what I'm looking for.
Still summer here in Wisconsin, but not for long. In just a few weeks the nights will start getting cool enough for heat and I'll be in hot water if I can't get the water to heat.
Thanks
Richard
Usually a webasto installed in a bus IN FACTORY CONFIGURATION is installed to be used as a suplemental heat source, in addition to the engine heat. In cold climates the 4 stroke engine does not produce adequate heat to keep the cabin and its passengers warm enough so the manufacturers install a webasto or equivalent. There are no separate fans for the webasto, it simply introduces additional heat into the otr system, and utilizes the otr fans and ducting. Many, like myself, have re-engineered the system so that it can be used as a stand alone system and install small cabin heat exchangers with low power draw fans.
Sent from my SM-G920T using Tapatalk
Quote from: richard5933 on August 04, 2017, 03:09:51 PM
We had a rather cool day today (mid-50s) so I thought it was time to test the Webasto to see if it would start. The instructions left by the previous owner consist of:
1- Pull switch to turn on.
2- Control fan speed with rotating knob.
3- Control temp with thermostat.
Not much to go on there. I pulled switch. The green light came on indicating something was going on. Only nothing really was.
Before digging in without knowledge, I thought I'd ask and see if someone could point me in the right direction.
The previous owner did leave me with a fuel filter and a replacement nozzle. Seems like he thought those would be needed. Beyond that I have no clue. I did find a manual in my stack of paperwork, but it was not much help either.
Richard
Okay, here is how a Webasto works:
1) There is an on-off switch to start the Webasto. The unit should start whining and if everything is okay the burner will start in less than 30 seconds. This circulates the coolant while it heats up to say 160f. It normally would pre heat your engine and the heater lines going through the bus.
2) The fan switch is to draw the heat out from the interior heater boxes and warm the inside.
3) The thermostat controls#2 but the Webasto continues to run and turns the burner on and off to maintain 160f in the coolant regardless of #2.
If the green light comes on and the Webasto does not start the Webasto is not getting electrical power. Get the downloadable instruction manual and check for power at the Webasto fuses. Then get back to us.
--Geoff
Thanks.
I'll be getting into the bowels of the bus this week and will see what I find. I've got the manual now and will see what things look like. I'm going to assume that there is a low current fan somewhere, because I've found a rotating switch near the Webasto start switch labeled 'fan'. From the looks of the switch there is no way it's large enough to control anything but a low current fan. Now to find it...
For anything Aqua-Hot, Hydro-Hot, or Webasto related, call Lloyd DeGerald as he is the authority on these systems. He is very knowledgeable and can send you any part you may need. He travels the country attending different RV related events and services these units. For his schedule, check out his website http://lloyddegerald.com/blog-1/ (http://lloyddegerald.com/blog-1/)
501-258-8426
lloyd.degerald@gmail.com
I made the executive decision today to throw in the towel on the Webasto and sent the unit to Lloyd for him to evaluate and repair. I could spend countless hours looking for a $5 part that went bad and end up replacing parts unnecessarily. While I enjoy being able to fix things in house, sometimes it's just time to call in the A team.
Now if only I could send the OTR heat system to someone to troubleshoot...
Richard
I got the Webasto back from Lloyd and reinstalled. Seems my thermostat is bad, as if I jump it the Webasto motor will start and the burner will now light. Circulating pump doesn't work though, so I can only run the burner for a minute or two.
Questions about the circulating pump for those experts out there...
Right now, the circulating pump is plugged into the 'A' spot on the control box. There are two leads, brown ground and a black positive. Weird thing is that the wires have 12 volts going to them at all times. According to Lloyd, the 'B' connected should have power to the red lead at all times and to the yellow lead when the switch is on and the thermostat is calling for heat.
Seems strange that the pump is always on. I can easily wire a master power on/off switch to control power to the Webasto so that when in the 'off' position there is no power to anything.
Big question now is whether the circulating pump should be running at all times the Webasto system is turned on, or should it only run when the thermostat calls for heat? I'm of two minds on this. For power consumption savings I'd like the pump to only run when needed to bring hot water to the heater core to make heat in the cabin. But, if the circulating pump turns off prematurely the Webasto will not be able to cool itself down after firing or if there is a high-heat situation in the heat exchanger. Ideally I'd want the circulating pump to stay on for a few minutes after the burner shuts down so that the system has a change to cool a tad.
Any thoughts?
Richard
Webasto needs coolant circulation, or you risk blowing the overheat fuses, and then you are back into the poop.
A system would have 2 layers of control, the coolant circulation, and the temperature of the coolant being circulated.
2 pumps, one that takes care of the webasto, and one that circulates your heated reservoir to the heat exchangers in the coach.
An electric hot water tank has been used by busnuts as that reservoir, webasto circulates in and out of it to heat it, second pump pulls hot coolant out to heta the interior, and the electric element is available for use when a power pole is available, and no stink needed to stay warm when it is only cool, and not cold.
Good stuff doesn't come simple?
happy coaching!
buswarrior
Quote from: buswarrior on September 14, 2017, 03:55:11 PM
Webasto needs coolant circulation, or you risk blowing the overheat fuses, and then you are back into the poop.
And lighter in the wallet!
The current system uses a small tank mounted next to the unit on one side. It only holds a few gallons and is capped with a radiator cap. One the other side of the unit is a heater core, mounted in a steel box, with a squirrel fan below it. The heat from the Webasto is fed from this heater core to the interior of the coach as hot air.
There are two circulation pumps. The first is mounted immediately next to the Webasto heat exchanger and circulates the water between the small tank, the Webasto, and the heater core. This pump appears to run the entire time the Webasto has power, whether or not the thermostat is calling for heat
The second pump is used to circulate the hot water from the Webasto to the bus engine for pre-heat. There are two heater hoses that loop from the Webasto tank/heater core setup into the bus coolant lines. This circulation pump has a separate on-off switch so that the cold engine doesn't draw away heat from the inside of the coach when it's not necessary to heat the engine.
I'm not sure how things were originally set up on this system, but two parts of it are puzzling me right now. First, there is apparently not a way to totally disconnect the Webasto from power. The on-off switch is wired in series with the thermostat, and they only determine whether or not the burner fires. There is still power to the Webasto control box and to the main circulation pump. I'll remedy that easily by adding a continuous duty relay with a toggle switch inside the coach so that I can cut power to the Webasto when it's not needed.
The second thing that puzzles me is it seems the main circulation pump is set up to run continuously when the Webasto is powered up. The thermostat controls the burn, and the air circulation fan only moves air when the water in the pipes is up to temp. But, the water continues to circulate. I suppose that it is not any different from the boiler at my shop - its circulation pump runs 24/7. My concern is about drawing down my battery bank when dry camping. I could wire the circulation pump to shut down after the burn by tying into the circuit that powers the main blower. The main blower runs for a couple of minutes before firing, and then stays on for a few minutes after the burn. My fear is that if i don't have the circulation pump running enough I stand the chance of an overheat situation or of not cooling down the unit after it fires.
This last puzzlement is what I'm looking for assistance with. Is it okay for the main water circulation pump to run all the while that the Webasto is powered on? If not, how would I best control it coming on and off?
Richard
You would surely draw down your batteries what with the Webasto motor and circulation pump. The pump runs all the time, as you noticed.
Personally, me....just me, not anyone else, I would never run a Webasto on batteries. I run mine with a 110v power supply which delivers about 13v DC.
Years ago I had a unit running on batteries, voltage got low. I think they power down at 10v maybe, I forget. Volts were low and the fuel wasnt atomizing as well as it does with good voltage. This caused "dribbling" of the fuel, which in turn cause the flame to splash back, etc, etc. Burnt up the whole inside plate with the wires and eye on it.
Opus - That certainly something to consider. Don't want to cause a fire or damage the unit. Lloyd warned me about running with low voltage.
We've got an alarm on the battery bank that screams at us at about 12.1 volts.
Our battery bank is about 550 Ah. I'd hope that with nothing running besides the Webasto, the fridge, and a couple of LED lights we'd be able to go a good way through the night. Not sure though. Anyone have an idea how much current the Webasto takes? I've read 60 watts, but that was by no means definitive.
We've got a 13kw generator that can be powered up to run things, but it's noisy and of course has a pretty good appetite for fuel. Running on batteries would give us at least a few hours of quiet.
Richard
Happy ending to the story.
Got the Webasto back from Lloyd. Looked better than it probably has since it was first installed. Got the unit re-installed. It would now fire if I jumped the contact as Lloyd instructed, but would not work otherwise. Here's what I had to do to get things working:
-Replaced thermostat inside coach.
-Replaced main water circulation pump & secondary pump which bypasses the heater core and sends all the heat to the engine for pre-heat.
-Replaced the fan-control thermostat which senses hot water before turning on the air circulation fan.
-Removed exhaust pipe to clean out mouse debris and nests.
-Added master power relay to eliminate any possibility of phantom current draw when not using the Webasto.
My only task left is to investigate all the various places the hot air is supposed to be blowing inside the coach to make sure that they are all open and sending heat.
Thanks to all who offered advice.
Richard
Quote from: richard5933 on September 19, 2017, 12:22:34 PM... My only task left is to investigate all the various places the hot air is supposed to be blowing inside the coach ...
Not quite -- there's the finding an old shoe box so you can cut some rectangles of cardboard to pad your wallet out a little bit so it won't fall out of your pocket. $$Ouch$$ (but worth it, IMO). Glad you got it done.
Yeah - it cost a few shekels. About $550 for the initial rehab on the unit itself including a new fuel pump. Another $300 or so for the main water pump and its fittings, and about $75 for the secondary pump and fittings.
Given the options for replacing it with something else, I think that I'm still ahead of the game.
The only thing that still puzzles me is getting the heated air inside the coach. So far I've only found three vents connected to the air circulating fan - two of them in the center of the coach near the unit and one more further down the same side of the coach. I've got a theory that the air is also being pushed into the main air chamber for the OTR HVAC system, but since the squirrel fan doesn't move that much air to begin with it's hard to tell. Probably on a day when it's not in the mid-80s I'll get a better idea of where the warm air is going/not going..
The original setup for the Webasto in this coach is to heat water in a heater core, and then push air through that heater core to heat the air inside the coach. I was told by Lloyd that I can add additional heat to the inside by adding a couple of baseboard heat registers to the loop with the heater core. The Webasto puts out more than enough BTUs to do this, but I'd have to find somewhere to run the heater hose from the middle bay all the way to the bedroom in the rear of the coach. I'm certain that will be the cold spot.
Anyone else add hot water baseboard registers after the fact?
Richard
http://www.parts.rvhydronicheaterrepair.com/Heat-Exchangers_c13.htm;jsessionid=14AEDCE3DA6321D09D08907CEA4269C6.p3plqscsfapp005 (http://www.parts.rvhydronicheaterrepair.com/Heat-Exchangers_c13.htm;jsessionid=14AEDCE3DA6321D09D08907CEA4269C6.p3plqscsfapp005)
this might work
dave
Not after the fact but this is 3 of my 6 heaters, maybe one of these would work:
(https://i.imgur.com/ySrqN2Ih.jpg)
Wow - that's one bright yellow floor...
After I got done wrapping up work on the bus today and after putting away all the tools, I realized that perhaps I know why there is no heat coming from the back of the coach. When I redid the bedroom area I stuffed lots of insulation into lots of empty spaces, including around the (I thought) unused vents. Perhaps those empty spaces were actually designed to route the heated air to the vents. I'll reopen the decking under the mattresses tomorrow and see what I find. Hopefully I'll be able to get the heated air flowing to the bedroom again. Sure wish I knew how the original converter set this thing up. Right now I feel like I'm putting together a jigsaw puzzle without the picture on the top of the box.
Richard