New owner of Vintage Bus 1980

[Joe Camper]

My bus in Chicago in 32 degree weather went like this.

If i used the electric block heater it was 4 hr. 2 hr point was more than enough warm for an easy start but to get it toasty warm like about 4hr at 32 degree.


If i used the espar the burner would begin to cycle in and out at about 45 min.

[freds]

My bus in Chicago in 32 degree weather went like this.

If i used the electric block heater it was 4 hr. 2 hr point was more than enough warm for an easy start but to get it toasty warm like about 4hr at 32 degree.


If i used the espar the burner would begin to cycle in and out at about 45 min.

Thanks for the feedback Joe.

[Gil_J]

More good stuff!

[freds]

Just finished a big project mounting the solar panels on my bus. I would say I averaged one panel a day for the installation as I was doing it by myself.

I installed ten LG375N2W-G4 panels on the top of my forty foot bus. These panels are 375 maximum watts apiece.

Here's the head on view from the front of the bus:



Here's a view looking back along the top of the bus:



Here's a side view of the first three panels:



In this view you can see that the first two panels are mounted in a slope for hopefully a little bit of aerodynamics though I know that this is probably a dead zone given the almost flat front ends on our buses.

This arrangement only adds about an inch to the clearance height of the bus. I didn't continue with the panels going straight back so as to give the air-conditioner hot exhaust a chance to go upwards and not heat the following panels which would affect their efficiency.

Given the poor aerodynamics of our buses all reports that I have heard is that there is no change in fuel efficiency for mounting solar panels. I don't have a base line on this bus, though the previous owner reported 9 MPG; which given his other statements I would discount.

Here's a side view of the last seven panels:



Note the very last panel behind the rear air-conditioner is also mounted low to allow the hot air to raise.

I think a nice side effect of this arrangement is that the roof will be shaded and the solar panels should have good airflow to help cool them. Also most of the rain will hit the panels and then run off the sides.

[PrevostNewbie]

Wow, Amazing work, will you have enough space to service the roof AC units? Or maybe just unbolt the panel and move it to the side? I am installing 3 new penguins on mine this week.

[freds]

Yes the plan is to just unbolt one of the panels and move it aside. My current units are quite old, so if I need to replace I would think a newer unit would be more low profile.

[PrevostNewbie]

I bought the Penguin II's, they were the lowest I could find. My last RV had a Dometic Brisk 2, that was taller than the Penguins. You could integrate the AC units into your Automation also, since the new AC boards won't be compatible with the stock thermostat if that's what you have in the bus. you could track the AC run time and cycle them based on avail battery and solar power/Time of day/ and weather conditions.

[freds]

I am going for functional first. The current unit's are really old school where you manually control them. So using a network power switch to toggle them on and off as needed. At the moment I am going for base line functionality.

I am using Shelly EM1 switches which also give a read out of power consumption on the circuit that they switch.

[freds]

Well hey the bus now has heat since I got the zone fans working!!!

The bus was previously setup with each heater outlet having it's own manual fan control switch, can't have that with my automation/smart bus goal LOL!!!

Anyway I decided to change out the old fans with Noctua NF-F12 iPPC-24V-3000RPM Fans.

In the PC world Noctua has a great reputation for quite and long lasting fans. I went with 3000RPM fans for when I need maximum air movement.

This series of fans have what is called a four wire interface where the fan's speed is controlled with PWM (pulse wave modulation) signal.

The four wire interface has the following wires:

1. Ground
2. Power
3. PWM control
4. RPM feedback signal



I don't use the RPM feedback signal in my configuration.

In my DIY hydronic system I have multiple heat zones in the bus, with control of each zone done by switching the power on/off for the pump and the fan associated with the zone.

My bus automation controller is Raspberry Pi 4 running NodeRed. The Pi has two pins that can be assigned to do PWM under hardware control. However only one pin can be used at a time for PWM.

Given this I currently have the PWM control line shared by the different fans in each zone. I could add separate cheaper Raspberry Pi's and have each zone be adjustable.

The initial NodeRed flow that I created is very simple.



It consists of just three function nodes:

1. Set initial msg.payload on startup to 50 which means 50% fan speed. (Note I took my snapshot after I manually set the speed to 100%.)
2. GUI slider control that allows the user to change the speed on the manual control web page.
3. Generate the PWM signal on the GPIO12 pin.

This is just my starter flow it will get a bit more complex when I add voice control via Alexa. I might also add logic to run the fans at full speed if the delta to the target temperature is greater then ten degrees.

If you are not doing automation you can purchase cheap add on PC fan controllers that you can manually adjust, otherwise when you give these fans power they run at full speed.

Another attribute of Noctua fans is that you can set the PWM duty cycle to zero and the fans turn off. Not something all generic PC fans can do.

Anyway it was easy to change out the fans. Here's the old fan:



And the new Noctua fan:



Actually this last picture show's me accidently installing the fan backwards, opp's!!!

Test before you close up....

[freds]

I thought I would post about my adventure in getting the solar panels mounted on my 1980 Prevost bus.

I guess the moral of this story is to use the proper tools!!!

This adventure was delayed as I thought I would have to bend offset brackets and was figuring out how to get them bent correctly as I thought the length of my panels was less than the width of the bus. It was a measurement error on my part as I used a two by four that was close to take initial measurements. I should have boosted an initial panel up to the roof for a more accurate measurement. By totally serendipity the length of the panels (77 inches by 40 inches) exactly matched the mounting points on my bus!!! So no need to bend brackets!!!

Anyway here's a picture of the offset brackets that I so proudly made to mount the first solar panel at the rear of the bus.



Using a bench vise you have to plan the order of the bends based on the distance between the top of the vice and the space to the draw bar. I used a vise mounted four inch metal brake from Harbor Freight.



Like I mentioned earlier the my solar panels LG375N2W-G4 were an exact fit to use flat plates as standoff's on my bus. The previous owner had a very accurate paint line that was I able to key off of when installing these supports. The roof structure on my bus is aluminum sheets installed over a metal frame. This results in a hollow square tube that I could drill into to install rivnuts for mounting the panels.

Drilling through aluminum and then steel rapidly wore out my drill bits and I kept having to buy individual bits until I broke down and brought a drill sharpener. Nothing worse then being at the top of ladder and having dull tools to work with!!!

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I was working alone so the next item on my learning list was how to get the panels properly into position!!!



I started off using wooden blocks that I had on hand, however this lead to a comedy routine of going up and down ladders repeatedly on both sides of the bus. Which had friends commenting "hey have you lost weight?" to which I would say the answer was yes, lost count of the number of times I have been up and down those ladders!!!! The solution was to get light weight jack stands to accurately position the panels before starting to drill.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Speaking of ladders and proper tools. I initially started using an extension ladder that I had split into two pieces. In the case of my ladder this results in one piece missing a rung which I came very to regret as I had to position a step ladder next to that section to get past the missing rung. I just bet you can see this coming, but at the end of one day I forgot about the missing rung and wound up ringing my chime on the pavement!!!! I also sprained the thumb on my right hand which is still bothering me three weeks later.



Needless to say I broke down and immediately purchased a telescopic extension ladder for the bus.


https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I have also purchased a number of thick kneeling pads for use around the bus and have zip tied one permanently to the ladder to protect the paint when placed on the bus.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Enough for today, will do another post of consumables that I used to mount my panels.