Dashing Thru the Smoke

After returning Hapy to service, I have not driven him much. As has been true for most of the time we have been together, he doesn't have heat. So it's like driving in an ice fishing shed... which probably brings some appeal to some folks, but it's not my favorite. Still, if I had to get somewhere and I could get there without using freeways, I would and have drive(n) Hapy. Why not freeways? This time of year, as I am sure you have noticed, drivers are especially distracted and others are driving specially, uh... nasty. This old bus needs more braking space than modern cars but other drivers don't always recognize that. When you add those factors together, it is tough sledding in the bus. Add in wet or slick roads and it gets scary. Regular roads are bad enough, but freeway speeds are too scary in the winter for me and the bus. With this backdrop, I start today's post.

Smoked Again

can you spot the loose wire?

A few years ago, on the return drive from 4Peaks, we were greeted with smoke billowing out from under the dash (See 4Peaks 2018 - Road Report). Somehow the ignition sub-harness had fried, leaving us stranded, riding home on a flatbed again. There's a song lyric in there somewhere. Anyway, I fixed that once and then again in a not-to-my-best-liking way with now 2 keys to operate the bus: one to unlock the steering and one to start/run the engine. This is working well enough so I leave it alone.

The other night, I had to drive out to Hillsboro for a final recording session with the band I'm playing in (shameless plug: Sunkicks), and Boo had not returned from work. So, I pressed Hapy into service. With the new starter and better glow-plugs, he fired right up and hummed like he was ready for some fun. It was damp out, so the lack of heat meant drying the inside of the windscreen with a towel, but for the ride out, it only needed that one wipe down. Even the driver door closed without too much trouble. It was like Hapy was really trying his best to show he was a real car and could be used reliably. We stopped for some home repair parts at the big box home repair store and he started right up afterwards. Again, "I'm a real car".

After the recording session concluded, the temperature had continued to drop, while the moisture held steady so the interior glass was quite foggy. Hapy fired right up and I flipped on the running lights while I refamiliarized myself with the controls in the dark. I thought I had the switch for the fans in my hand, but it was actually the headlight control... I turned hard it to the right (the fan control switch has always been a little resistant), and rather than turn on the fans, I caused something to ground, causing a wire to release it's smoke. When I saw the smoke, I turned the switch back left (anti-clockwise) but the damage had been done. All that was left was to figure out how widespread it was, and to apologize to Hapy; this wasn't his fault, it was all mine. The smoke was pretty bad though, considering the windows were closed, the bus wasn't moving and the fan wasn't on. The next day, my throat was still sore from it. When I opened the driver window, it must have looked like a scene from Fast Times at Ridgemont High with the billowing smoke rolling out.

dripping blue

Starting with the positive... the engine was still running. The cooling fans were on and could be turned on and off. The defogger (doesn't defrost, hardly de-fogs) fan could be turned on and off. As to the negative, the driving lights were out, I think the tail lights were out and there was an annoying buzzer like a seatbelt warning was on. When I flipped the turn signal or hazards, the front lights flashed correctly and the buzzing went away. I was still sitting, idling in front of my bandmate's house, so I decided that I would just drive home and deal with it later.

The drive home was quite uneventful other than the constant buzz noise and concern that drivers behind me could not see us nor tell when we were braking. When I got home, the engine and fans shut off without issue. It was too late and too dark to diagnose, but my hunch was that it's the wire that sends a signal to the running lights.

Wire Still a Puzzler

A few days later, when I could go out to the bus in daylight, I went out and removed the headlight switch from the dash. I could see one of the wires had become detached, but I was unable to see any truly fried wires. Puzzled, I plugged the wire into the open pin on the back of the switch, and tried the lights. Yep, headlights still turn on, dash lights still turn on.... running lights turn on. All of them, including the tail lights. So, I pulled on the hazard switch. Dash directionals flash, front directionals flash, rear directionals flash. At this point, I don't know what's fried, but the engine starts and runs, the cooling fans fire, the dash lights, switches and gauges work and all the lights work. In the middle picture, just above, there's a light blue orb thing on the lower left side of the image. That is a blue drip that I cannot account for, but I think something melted and that's the result. Neat.

I think it is time for me to determine which of the original circuits no longer need to be served and at the very least remove the fuses. After the cleanup I did in the back for running the engine, I think it would be wise to plan to do something very similar up front. I mean, in the end, the only things the "main" fuse box is running now are the dash, and the lights. That's like, 4 fuses tops? Regardless, this exercise should lead me to the smoked wire and reduce the electrical gremlins.

Furnace Update

furnace control board

Our electrician is semi-retired. He used to run a HVAC company and has installed literally hundreds of furnaces before focusing on general residential electrical instead. Now, as he is slowly divesting of his electrical business, he has observed my work on our furnace. In a fit of holiday fever (he swore off furnace work years ago), he popped by for a couple of hours, got the gas line hooked up and leak tested as well as the 110V electrical feed completed, with a worker shut-off switch. He even got most of the exhaust venting put in. He hit a wall when he was unable to connect the control cable because the access screws are hidden behind a panel that you can't get to once the first piece of exhaust venting is attached to the furnace. That's some poor design.

Still, I saw the furnace project as 7 big individual efforts: demo/move/mount, conditioned air distribution, cold air return, gas, electric, exhaust vent and the thermostat/control cable. I had completed the first 2. He knocked down 2 more (gas and electric) and set me up to get the next 2: thermostat control and exhaust vent. Once I have that done, he will confirm things, and test the system. Then, I just need to get the cold air to pull from inside the house and we have a complete system. For testing purposes, I may simply smack a filter on the plenum.

Since I started this thread, I caught a cold, celebrated Christmas and installed the thermostat control cable. As I indicated, I had to remove the exhaust venting all the way to the firebox before I could remove the panel which covers the control board. I ran a new wire from beneath the furnace (where the old one entered) and connected the control wires. Before putting everything back together, I took the opportunity to spray the snot out of the control board with a can of computer-cleaning compressed air. I figured that panel won't be coming off anytime soon, so may as well get the board as clean as I can. After that, it was simple replacing that which was removed, re-using the same fasteners.

That's about where things are today. Hapy appears operational, and I will be test driving him here in the next couple of days. The furnace is almost ready to test. I need to complete the assembly of the exhaust vent and properly suspend it from the floor to retain the correct exit angle, but I think that is a couple of hours effort at most.

Thanks as always, for following along. Have a peaceful, pleasant, hapy new year-

Completing the Furnace Conditioned Air

In my last HVAC/furnace post, I had described the conditioned air plenum, and my efforts to create and then attach one. Today, I get on with the rest of the "conditioned air" venting. As before, I call it that so there's no confusion between the venting that has the output from the furnace and the venting that is the cold-air return side that feeds the furnace.

Rectangular Vent Prep

long arm

Recall that the crawlspace in this house had been infested with rodents. I mean it was bad. We had it emptied of rubbish and insulation by a team who seemed borderline hazmat. The work was disgusting, that team was amazing. They replaced some, but not all, of the circular vents with insulated flexible venting, but left the larger rectangular trunk lines. Perhaps they thought those vents were clear and clean or maybe they just wanted to complete the job (not that I blame them). Those vents were unobstructed, but far from clean. I had intended to clean them in-place with a microfiber cloth on an extendable pole. Once I got to really looking at them, I knew this was simply not going to be sufficient, and chose to ignore the fact that these vents were used last winter. Yuck.

ga-ross

To remedy, I dismantled them, and hauled them piece by piece out of the crawlspace into the backyard. Using the highest pressure setting on my hose-end sprayer, I jetted off the worst of the caked on filth, inside and out. Then, with a scrub brush and dish-soap, I cleaned each piece inside and out. Once rinsed, they were set aside to dry and I took one of my most-needed showers ever. The insides are clean, but I noticed a very slight brown staining. I concluded that it's probably from many years of people smoking tobacco in the house. I considered spray-painting all of the inside surfaces, but decided that the off-gassing of the paint was worse than whatever caused a stain (but was now gone). I did, however, spray paint bits of the outside of the venting which had rust or remnants of the old fabric (asbestos-imbedded?) tape which was removed by the hazmat guys.

Rectangular Vent Install

cleaned

Once cleaned, partially painted and moved back into the crawlspace, I was ready to start installing. I started at the furnace and worked by way out. First were the bits that connect the plenum to the rectangular vents. These are angled and change shape from one end to the other, converting whatever size hole you had in the plenum to the size of the vent. I found that by bending the lip wide open, the piece fit easily, and then just fold the lip back against the inside of the plenum. With high-end foil tape, I sealed the seams from inside the plenum.

I read about and considered using a brush-on goop to seal the seams but decided that painting goop while army-crawling around a filthy crawlspace just did not sound like a great idea. Consider too, the goop seals as well as tape, for the most part, and it's effectiveness is directly tied to user application. So, again, lying prone (or supine) with a brush of goop sounds like errors would abound. Taping is hard enough when you're lying down.

Once the 2 main bits were connected to the plenum, I first did a 90* turn bit on the smaller distribution arm (8 x 12 rather than 8 x 18) and then shifted to completing the larger arm. This took many hours, even though there were only 4 sections. For each section, I would wrestle the rectangle into the connectors on the end of the one prior. I used another section of HVAC to hold the far end up while I fastened the new piece to the old with sheet metal screws. Then, I suspended the far end from the floor with nylon webbing stapled to the floor joists above. Once free-standing, I sealed the seams with that high-end foil tape and then wrapped the vent with (R8) foil-wrapped closed cell HVAC insulation. I expected the venting to take a little while, but did not anticipate that the insulation step would take maybe twice as long as the venting assembly. I took care to seal up the insulation seams, but the time was consumed by, again, lying down and wrestling large rectangular insulation panels, trying to wrap them around a rectangular vent which had circular vents jutting out of it. I don't know if having the insulation sealed up tight matters much in the grand scheme, but I made sure they were relatively well sealed anyway. I spent probably 8 hours in total getting the larger arm assembled and insulated.

original round vent

Before I moved to the smaller arm, I attached the round vents to the larger arm. I had initially intended to remove the original remaining round vents, believing they were not up to snuff. While I was assembling the larger arm, I looked at the 2 remaining larger circular vents (picture on the right shows what condition they were in) and while there is some dust and more brownish stain, there is no rodent evidence. What I did not expect was just how close the rectangular venting is to it's original location. The round outlets on the rectangular vents are a few inches off center and less than a foot away from the original. So, I placed a short stretch of insulated flexi-venting between, taping both the inner hose and the outer insulation wrap at both ends. I did not capture a close-up picture of that, but I found that these sections were so short that it was actually easier to remove the inner sleeve from the insulation, attach it to both ends and then wrap the flexy-hose with the insulation jacket afterwards.

Smaller Arm

When I changed the vents around on the larger arm, I inadvertently removed the vent intended for the bathroom. I will re-integrate that later. The bathroom floor vent has not been connected since we first got the house. Recall above where I described where I made the cut in the plenum, I removed another vent access, which was direct-connected there, to the bedroom. Since it was not part of the air design plan for either arm, adding it to one or the other could upset the pressure for the other destinations. Since the bigger arm distributes to the west side of the house and the smaller arm goes east, I decided to tie it into the east (smaller) arm simply because that's the side of the house the bedroom is on. As it stands, the smaller arm only had 2 destinations (the kitchen and one main living space) so I felt adding a 3rd there would be less intrusive than adding a 5th destination to the larger arm. Also, I considered that the kitchen is an uninsulated space, cordoned off from the rest of the house with plastic. I decided to connect the bedroom to the used-to-be-kitchen vent in the smaller arm. When the kitchen is ready for a vent, I'll cut a hole and tie it in or I will move the bedroom connection back to the plenum.

short arm completed

The smaller arm took less time, and other than threading new stretches of flex-hose from the arm to the vents, it was a reflection of the larger arm work. Each arm-piece-to-arm-piece connection was metal-screwed in multiple spots, foil-taped and suspended with webbing. The entire arm was insulated with the R8 closed cell stuff, each circular connection was double-taped (inner tube and insulation jacket). The only real anomaly was with one rectangular-to-circular connector not aligning between the floor joists because of the furnace move. To remedy, I simply flipped it upside down (see picture on the right) so it is on the bottom instead of the top. I'm sure some HVAC person somewhere doesn't like this, but it fits, and it's sealed. All told, building the large arm took a weekend while attaching the circular vents to it and doing the entire smaller arm took a second weekend.

At this point, it had grown dark on a Sunday afternoon/evening. So, I picked up my tools and supplies and put everything away. With some scrap paper and a pen, I started contemplating the cold-air supply side. I will start that work next, but I think getting the "conditioned air" / distribution part completed was a significant milestone. Sure, I still need the gas hooked up, the exhaust re-assembled and suspended, the cold air return I just mentioned, the trigger wiring done and, last, the electrical (and walk thru by our electrician / HVAC guy). Yes, that is a lot, but I feel like the largest, hardest part is now behind me. I know... "famous last words".

Thanks, as always, for following along-

Starting to Solve for the Furnace Conditioned Air

If it feels like this furnace saga is unending, it definitely feels that way on my end. Every passing day, the weather gets colder, but I will not short-cut this work. It being correct is too important for health and safety. I do want to stress that our electrician, Gary, owned an HVAC company and did hundreds of furnace installs. He consulted on the plan and will be reviewing my work / confirming everything when he connects the electrical at the end. So, we keep going. Honestly, the hardest part is putting on cold clothes in a cold house to get into an even colder (and, frankly, filthy) crawlspace.

Anyway, today, I am focusing on what I refer to as the "conditioned" air. This is the air that is leaving the furnace, presumably warmer, but on those days we are only running the fan, it will just be filtered. For simplicity, and since this was the way I did it, we are working from the furnace exit to the floor vents. Sadly nothing was as easy as it seemed in my head, resulting in this expanding to cover many weekends. This is just the first part of it.

Furnace Mounted

checking pitch

Before I shift to the new topic, I had a couple of final things I needed to do with the furnace: confirm the pitch and attaching it to the stand. To confirm the pitch, I found a straight bit of hard plastic tubing that was over a meter long. At exactly 1 yard (36 inches or 3 feet), I attached a 1 inch thick piece of scrap wood. Recall the minimum pitch for the exhaust from a furnace installed on it's side is 1/4 inch of rise per foot (or 1 inch of rise per 4 feet). I figured that if I made sure my work was at 1 inch per 3 feet I would have exceeded the minimum and have some wiggle room for the furnace or the ground shifting. I set the plastic tube jig on top of the furnace and set the level on top of that. Bubble between the lines? Yes, so somewhere along the way between my level crawlspace patio and the top of my furnace the world tilted. Glad it pitched the right way for me. I had planned to shim the exhaust-exiting end. Do I want to know why it shifted? Yes, but I think because the furnace is offset rearward (you can see the stand in the lower right corner of the picture), the weight of the burner is causing the tilt.

Feeling fortunate, I grabbed a longer run of that plastic tubing to simulate the exhaust from the furnace to the chimney and set the jig on that. We have good angles, though I will need to add a brace near the chimney end to make sure it doesn't relax downward over time because the exhaust needs to enter the chimney near the top of the hole. To make sure the rest of my efforts don't cause the furnace to move, I sent sheet metal screws through the now-bottom of the furnace into the stand so it is fixed-in-place. I re-checked the pitch, and it is still 1 inch for 3 feet even after sending screws through. On to the conditioned air!

Plenum Pablum

building a plenum

The first thing the conditioned air enters is a box called a "plenum". It acts as a singular junction box for all of the conditioned air, but it does more than that. Consider what happens when your furnace kicks on. The fan starts and very quickly air pressure increases at the furnace outlet. To cushion the system from that large pressure increase, there is the big box (plenum). Secondarily, this box allows the air to flow smoothly and evenly into the ducts. If the box is too small, or nonexistent, the air would not enter all of the vents evenly, leaving some spaces with too much airflow and others getting an old microbus heating system experience (virtually nothing). I am over-simplifying it as there are air dynamics about back pressure from the branch lines, etc. that I really don't understand.

The original plenum to this house was just that. The original plenum, as in it was the plenum when the heat source was something other than gas, we believe. I think it may have been coal based on the soot we have found and then oil since there's an old oil-tank shed in the back of the house. Still, airflow is airflow and if the thing that is pushing the air is heated by coal or wood or geo-thermal fanciness, and the venting beyond the plenum is the same, I would expect the plenum should be relatively the same. Of course, 15 years after the house was built they added 2 rooms to the back, so maybe the plenum has been the wrong size since. I suppose, this could be a recently-added bit, but none of the other metal venting looks remotely new.

furnace entry

The plenum was almost a meter tall and about 2 feet square. From my research, this is excessive, but was unable to arrive at a clear answer as to what size it should be, like with a calculator or simple rubric. The most basic advice seemed to be "make it a little bigger than the outlet of your furnace". I am fairly sure that would lead you to a too-small plenum and poor circulation impacts, but I defer to experts. Regardless, I took all of this and decided that I needed the plenum to fit in the space I had, so if it was smaller, well... we'll just deal with it and worst case I'll make another one later. I simply built what would fit in the space without digging again. 

Plenum Fab-lum?

So, what did I do? The original plenum had the air enter from above and then it routed air sideways out 2 rectangular vents and one round one. In order to keep the orientation of the rectangular outlets, I needed the top covered and a new entry added on one of the other "horizontal" sides. In order for the 1-meter-tall plenum to fit into my not-quite2-feet-high crawlspace, I needed to shorten it too. So, I measured and then cut (with the death wheel) 9 inches down from the top in each of the 4 corners. Then, I folded the sides in like a cardboard box. With a hammer and dolly, I squared the newly folded lines. Content with the shape, I drilled and then pop-riveted the new top in place (upper image). Last, I sealed all of the edges with high-end foil tape.

Plenum added

So, I have a box, but no entry for the furnace. Onto the side which had a circle-vent, I applied blue tape and then measured the dimensions of the furnace exit. Half an inch inside this rectangle I marked the actual cut line. That extra 1/2" will be the lip which will press against the exit "flange" on the furnace. I cut the hole with the death wheel, turned the lip with some pliers and cleaned up the fold with the hammer and dolly again. The circle-vent used to feed the bathroom, which does not currently have a vent. If we re-introduce a vent into that bathroom, I can re-integrate it into the system.

I lowered this new plenum into the crawlspace, army-crawled it past the furnace and attached it to the furnace. It barely fits between the ground and the floor joists, but it does and it did not disturb the angle of the furnace. Once it was in place and the edges sealed, I was ready to look back at the main trunk / vent lines (the big rectangular ones).

As often happens when I get to posting about something, this got very long. This feels like a logical transition point so, I am going to stop here, and pick it up next time. Thanks, as always, for following along-