Fixing Hapy Furnace (part 2)

Picking up where I left off the last post, Hapy has an operational furnace again.

Fuel Pump Swap

As I mentioned in my last post, the fuel pump which originally delivered with the heater/furnace would not work when I tried to bring things back to life. I splurged and bought a more expensive "quiet" model for $50US rather than another standard pump for $20US. I figured quieter or not, the more expensive pump may have better parts in it, and it may last longer whether it is quieter or not. Or it was just a marketing gimmick and I got took. Let's chalk it up to the cost of an experiment.

The old fuel line path was relatively simple. The "hard" (clear but firm plastic) lines that delivered with the furnace had short (50mm / 2-inch) stretches of fuel hose between them and the pump. The pump was suspended from a cross beam by the included rubber mount held in place by a single sheet metal screw. After a few turns with a screwdriver, the pump was on the ground. A few more and the fuel lines were removed from it. The supply fuel line started dripping fuel after a few seconds, so I caught it with a pan. The line on the pressurized side was completely empty, so no drips. I simply reversed the removal: added the rubber mount from the supply end of the pump, added the supply fuel line, suspended the pump from the cross beam and then added the pressurized-side line.

Prime and Fire Up

The Afterburner has a control page where you can direct only the fuel pump to fire up. This allows you to get fuel all the way to the furnace without the glow plug turning on (drawing the battery and maybe burning out the glow plug). I had not connected the pressure line to the furnace, but I wanted to clear the lines of any bad fuel, so I moved the pan under the dangling hardline and triggered the Afterburner to prime. Within a minute of the prime starting, fuel started spurting out the end of the line. It took longer than I expected it to, but perhaps that is an indication of how little fuel these units actually consume. Once the fuel leaving the pressure line looked like the fuel supplied at a filling station, I stopped the prime function and connected the hardline to the fuel hose dangling from the furnace.

While the pump was slightly larger than the original, it did not seem much quieter during the prime. Of course, I hadn't heard it pump in a couple of years, and memory is a funny thing. I do recall that when the furnace was running, I could hear the tick-tick-tick of the fuel pump over the whoosh of the furnace. With this in mind, I set the furnace to start. I did not want to consider the experiment with the new thicker, dedicated wiring yet, so I left the battery tender hooked up. At no point did the battery fall below 13.5V so either the tender was working hard, or the new wiring is a hit.

Regardless, the glow plug got lit, the fan started spinning and after 2 or 3 minutes the furnace ignited. This felt like a considerably longer period of time than before. Perhaps the priming was incomplete and I needed to prime again after connecting the hose to the furnace. Perhaps it took time to ignite simply because it had been so long. Once it ignited, a huge plume of smoke poured out of the little muffler. There was virtually no wind, so the cloud grew and sat slowly obscuring first the rear end of the bus and slowly 2/3 of the bus before a light breeze broke it up. After a few minutes, the cloud dissipated and the exhaust emission was reduced to nothing. All that remained was a light smokey haze inside the bus. I regret not taking a picture of that.

Noise Observations

While the temperature inside the bus slowly crept up from 55*F (13*C), I noted the noises. I could only hear the fuel pump ticking inside the cabinet where the furnace is located and even then, only when I stuck my head into the cabinet. I think the pressurized line is transmitting it. I stuck my head into the rock-n-roll cabinet above the spot where pump is actually installed and could not hear it. Maybe this new pump is quieter. Then, I moved outside where in the past I could clearly hear the pump from several feet away, even from the passenger-door side. I could not hear it, but I could hear the furnace whoosh. Of course, my muffler-ing of the furnace is different this time, having removed the second small rectangular muffler and the motorbike muffler. Perhaps the pump is no quieter, but the furnace is that much louder. To determine if the muffler configuration is a variable, I decided I will conduct another test at a different time, after re-attaching the other muffler bits. I had thought about bringing them along for while-parked use, and maybe I will need to, out of respect for our festival-going neighbors. In the past, I took decibel readings, but they were for while the furnace held a temperature, not during temp catch-up (full blast).

I will continue to experiment with noise readings and post if I find any readings are different than they were 4 years ago. I expect that once I put the extra rectangular and motorbike mufflers on, the readings will be what they were before. The only real mystery to me is whether the fuel pump can be heard over it. At this point, though, the pump seems significantly quieter.

Thanks, as always, for following along-

Fixing Hapy Furnace (part 1)

Having finally arrived at a place where we have some heat while we're moving, I felt motivated to fix the heat for when we are standing still. Today's post covers most of the saga of getting a Chinese diesel heater operational again. Spoiler alert: the heater isn't running by the end of this post.

Brief History

Back in the early days of CoViD, I installed one of those Chinese diesel parking heaters into Hapy (See Parking Heater 1, 2, 3, 4, 5 and Final for deep detail). While I was able to run it a few times, I found that the heater pulled the voltage way down on whichever battery was connected to it. I tried to solve by providing multiple batteries to source from: one to start, one to run, but switching from battery to battery seemed like a bad practice. I had other priorities, so I just let the furnace sit unused. When I did the sound deadening effort and the luxury electrical re-wire, I dismantled the cabinet which housed the furnace so I could get sound deadener underneath it and electrical cables through it. This meant dismantling part of the furnace too. Later, when the band wanted to use Hapy for the album cover, I removed the furnace exhaust so it would not appear in pictures. So, I had a furnace without an exhaust, and would draw way too much juice.

Electrical

Over time, and with more learning about electrical stuff, I have concluded that the wire used to convey electricity but perhaps more importantly the wire for a ground were far too thin. It was due to these thin wires that the voltage would drop so badly as the furnace attempted to compensate. Wires which would have been barely up to the job had the battery been sitting right on top of the heater will definitely NOT be up to the task once you move the battery a few feet away. This is exacerbated by running the ground to the body of the bus instead of back to the battery. The ground location should not matter as much, but I'm citing it as a participant cause anyway. So, addressing the electrical came first after removing the furnace from the bus.

A small harness of wires leaves the furnace body and enters a black plug (see picture on the right). The harness that ships with the furnace includes a pigtail that clicks into the furnace black plug. To my eye, the red and black wires in the pigtail are not nearly as thick as the wires leaving the furnace. This probably saved the manufacturer a few pennies, but the amp draw issue starts right there (and in my case got worse). So, I cut the main power and main ground wires from the furnace black plug and put male/female wire ends on them (12V/ground respectively). I made them different so I couldn't accidentally plug it in backwards. I then prepped a thick 2-wire black/red cable with matching wire ends, and routed it over to the luxury battery. At the battery end, I added a ring terminal for the ground and added a 20Amp fuse into the positive side before adding a ring terminal on that end. I left things detached as I switched to preparing for the exhaust.

Exhaust

From under the bus, it was clear that I had not made the hole(s) large enough for the exhaust, intake and fuel to be easily maintained. Quite the contrary, I had installed it such that once it was all together, it would have to all come apart to fix anything. Frowny-face. So, I started by cutting a 4-inch square hole into the lower belly pan. Many buses do not have these, but I got lucky. Anyway, with the hole cut I could see where the furnace sat, and noticed that the exhaust was getting pinched by the too-small hole in the floor as the exhaust left the furnace. So, I went topside and expanded the upper hole both in the floor of the cabinet and the steel floor of the bus. With the larger hole, the exhaust easily fits and things could be maintained from below. Still, I did what I could on the furnace itself before lowering it in: Connect a 6" long stretch of fuel line, attach a small circle of window screen to the intake (so bugs and pebbles don't get in) and then attach maybe a foot of heat-wrapped exhaust. I set the furnace in place and attached a small subset of the muffler arrangement I had used before: just one rectangular muffler. I may bring the expanded muffler set up for use when we are in tighter camping spots (like festivals), so we can bolt-on some extra quiet. I mounted the muffler to the underside of the frame rail, with the outlet pointing rearward and slightly away from center (picture on the right).

A keen eye can see some fresh Rustoleum primer + paint above the muffler where I discovered some rust had eaten all the way through the body. When I was working on the other stuff I ground the metal down, removing the rust, but exposing the holes. Sadness. That rust traces back to when this bus had a small vent window directly above this spot. That vent window was badly leaking and the rust had already been forming to the point of marring the paint when I bought this bus over 20 years ago. I eliminated the vent window in 2015 (See Calling "glass") with a window I purchased from BusBoys in Redding, CA in 2009. Some things move slower than others.

Fuel

I shifted over to fueling at this point. The fuel line that had been between the included "hard" line and the furnace had breeched, probably when I did the sound deadening. The fuel in the line looked dark, so I dropped the line into an empty pail, and figured I would prime the fuel system, and purge the bad fuel at the same time. Unfortunately, the fuel pump is no longer functional, so I am waiting on a replacement to finish this job.

Afterburner

Back when I first did this job, I bought an Afterburner from the guy who hand builds them in Australia. Apparently, there are people building knock-offs, eating into his business, since they basically have cloned his work. So, if you are looking at getting the much nicer controller for your parking heater, please connect with Mr. Jones in Australia and get the real deal. Anyway, with the Afterburner, I tried to prime the fuel system, but the fuel pump wouldn't respond. When I unplugged the pump, I got a code; I concluded the wiring to the pump was good but pump was bad. So I ordered a new, supposedly quieter, one. We'll see. While I was clowning around with the Afterburner, I got it onto my home network, downloaded the newest firmware and wandered around the new-to-me website that the Afterburner hosts. It's really cool. I am looking forward to triggering the furnace to warm the bus from inside. For reference, here is a link to the user manual.

This is as far as I've gotten. I am waiting for a new fuel pump to arrive. I need to purge the old lines of nasty fuel, and install that new pump. I expect there will be other discoveries, and I need to rebuild the cabinet innards. There's always opportunities to improve things. Anyway, thanks, as always, for following along-

Hapy Heat Circle-Back

Brief post this week. I've been tearing down the electrical in the bus, and it's really not that photogenic. I'm not really sure how to post about it since it really is very boring from a read-all-about-it perspective. It does, however, take an incredible amount of time. I have spent probably 10 hours just slowly working through the circuits, figuring out what's what and then cutting and labeling things so I can put it all back together, but cleaner. So, while I figure out how to not bore people to tears, here's a quick update on the furnace.

Hapy outside townhouse
before Champoeg trip

As I post this, I am realizing that it was 10 years ago that my first marriage dissolved and, perhaps correspondingly, the TDI transplant really got legs. How time flies. Over the course of this next year, I will be hitting other 10-year milestones: getting my townhouse apartment (See Hey Strangers), that first camping trip with the boys to Champoeg State Park (See One Small Step for Van) in the TDI-powered bus, and meeting Boo (See Football, Friends and Further). Funny how 10 years later, we are still making improvements on Hapy, I am still fiddling with the TDI electrical and his exterior doesn't look much better. Where were we? Oh yeah, furnace fun.

 

Yeah Yeah, Follow the Manufacturer's Instructions

It's been a few months since I did the parking heater / camping heater install. As directed by the manufacturer, I have been turning the heater on and letting it run through it's cycles about every 6 weeks since. My last runs have been these last 2 weekends. 2 weeks ago, it was super cold (low 40*F's or ~5*C), so I thought it would be interesting to see how the heater sorted itself out. The heater had the interior of the bus genuinely warm in about 10 minutes.

 

Can't Leave Well Enough Alone

I thought I would experiment with the fuel pump frequency at the low end of the maintain cycle. This is the speed at which the heater would run when you achieved the target temperature. I figured that even at the recommended 1.3, the noise coming through could be disruptive when you're sleeping in the middle of nowhere. So, why not see if it can go super slow? So, I set it to 1, which is below the manufacturer's recommended low. I left the bus alone for a while to see if it could arrive at stasis. When I returned about an hour later, the inside of the bus was kind of exhausty-smelling. Yuck. I shut things down, and thought about whether I had an exhaust leak. I had not had that smell before, so either I hadn't run the tests long enough before, or maybe that manufacturer setting was related.

Not a Leak, Just a Bad Idea

Fast forward a week, and I'm ready to test again. This time, the temperature is just above freezing. I turned on the heater, using the built-in Afterburner WiFi, from my living room. This is so cool. So, I'm in my living room, and simply connect to the WiFi and go to 192.168.4.1 on a browser and bam, there's the controls for the heater. Tap on the thermostat image and a popup asks if you want to start the heater. Once that process started, I changed the fuel pump low setting back to 1.3. After about an hour, I checked the Afterburner browser on my phone. The heater was maintaining 68*F (20*C), and was in a maintain cycle running the fuel pump at 1.3. So, I put on my shoes and coat and went out to Hapy. No exhaust smell, just the smell of warm metal from the furnace. Of course it was totally comfy.

 

I now conclude that when you go below their recommendation, the heater still works, but I think the fan speed is somehow involved in the force at which the exhaust is expelled. Continuing this thought, since the fuel pump was set so low, the fan ran super slow, and the exhaust fumes built up inside the bus. Neat.

So, that's it for today. Basically, if you were wondering if you can run the heater at a setting below the manufacturer's recommendation, that answer is "yes", but the risk is not just premature wear. The greater, or at least more immediate, risk is that exhaust may not properly vent, so you could create an unsafe condition inside your bus. Thanks for following along-

Parking Heater - Final

In March, I posted a series about installing one of those inexpensive Chinese Diesel Heaters into Hapy, the TDI-powered microbus (See Parking Heater 1, 2, 3, 4, and 5). I have completed the little things that I had left undone, so today's post takes a break from the oil temperature and pressure stuff and wraps up the heater.

Power Switch

I had left off with a power switch wired between the main (drive) battery and the heater. It was dangling around in the cabinet behind the old refrigerator-turned-cabinet. I added a wire to the luxury battery housed under the rock-n-roll bed through the fuse box I have controlling circuits to that battery. I also bored a hole into the wood support I have in that rear cabinet holding the old westy battery maintenance panel. I don't really use that panel, mostly because I haven't finished wiring up shore power to charge the luxury battery. Anyway, I punched a 5/8" hole through and fed the switch through, nutting it down. It looks fairly finished now; it just needs a label.

Cabinet a Cabinet Again

floor back in.

The heater sits on the floor of the old refer cabinet. I only need about 7 inches of clearance, but I gave it 8-1/2 so I could add a layer of insulation later. At the 8-1/2 inch point, I attached 2 wood supports running along the front and rear walls. On top of these, I put a thin run of foam to reduce any noise or rattling, and then settled a rectangular board for a cabinet floor. In the future, I will probably attach some kind of insulation to the bottom of that floor. For now, it is just a bare piece of wood.

The smaller cabinet can still hold quite a bit of stuff. I re-stowed the zombie-apocalypse Red Cross first aid duffel, some paper products, and a few other fairly important yet random things (playing cards and a cribbage board, for example).

Afterburner

Afterburner installed

Afterburner unpacked

The Australian guy (Ray Jones) who makes the Afterburner appears relatively unaffected by the CoVid-19 lockdown, so he was able to process my order and sent it to me. Bear in mind, he is a one-man operation, so the waiting list can be rather long. I let the package sit for a few days in quarantine (on concrete garage floor) before digging into it. The included install instructions are easy to follow, and all of the parts are easy to identify. I had it installed, complete with wire routing and final wall mounting in a couple of hours. I have only scratched the surface of what this thing can do, but I am very impressed with it so far. In my opinion, the white case and grey buttons looks great. Like so many other improvements, this shows me how much I can raise the aesthetic simply by adding carpeting to the wall cards. All of the scratches in the picture on the right, here, highlights how overdue this is.

Afterburner operating

Okay, today's post was a little light, but all combined, those short passages took me hours to complete. More important, the heater is complete. Once I have the Afterburner figured out, I'll be able to pre-heat the bus in the winter time, have the heater turn on based on a schedule, shut off based on temperature, etc. Basically, it will have the same capabilities as a home thermostat... but in a 50 year old VW bus. This heater install was originally so we could get warm during the summer solstice music festival in Bend (4Peaks) which would have been next month had the CoViD pandemic not happened. Assuming everything is back to normal in June 2021, we will use it there. Maybe, just maybe, next winter I will be able to achieve my old dream of taking Hapy to the mountains for some fun in the snow.... now that we have a way to get the cabin warm. Hmm.. maybe I need to figure out how to add a defroster first.

Thanks again for following along. More next time-