Continuing the NewOld House construction, today's post is about disconnecting the furnace, and considering our options for what's next.
Hapy Update
I know I have not written much about cars lately, so here's a quick update on Hapy. I don't drive every day, but Hapy has been my main vehicle all summer. The other night, I grew frustrated with someone driving at least 10 mph below the speed limit in the left lane. I was cruising around 2k RPM in 3rd (around 30mph in a 45mph zone). An opening appeared in the right lane, so I stepped on it and started changing lanes. I guess I stepped on it too hard because I smoked the tires for a second before they grabbed, launching us forward. Goes to show, the KermaTDI bigger nozzles and Malone Tuning CPU chip were significant improvements. Since I have been driving him so much, it is now time to do his front brakes. I am still questioning the brake booster, so once the front brakes are done, I may revisit the booster and master cylinder. Since Hapy has become the gear-hauler for the band I've been playing in, taking him off the road has larger implications than ever. Anyway, back to the furnace.
Exhaust
furnace freed |
Cold Air Intake
On this furnace install, the cold air return/intake enters from above. So, while warm air rises and cold air drops, our cold air return was installed 6 feet up into the wall. Genius. It was simple to take apart, though. The protective grill was held on with 3" long screws, which also held the air filter in place. Behind that the HVAC flashing was bent to create a flute or trumpet-bell shape to route air from the grill through the hole in the wall into the main intake. From there, the intake took a 90* turn down into the top of the furnace. Easy-peasy. The intake was similarly held together with sheet metal screws, and it came apart just as easily as the exhaust had. The sole difference was that each seam had the fancy shiny duct tape. That came off fast too. Once in pieces and the trumpet-bell bits bent straight, the whole unit came free.
Hot Side
exhaust removed |
Electric
Next came the electric stuff. I started by removing the thermostat and the trigger cable from it to the furnace. We don't know if we are going to retain that thermostat, nor are we sure it is going back in the same spot. Either way, it was a standard 5-wire control cable, so re-installing it or doing net-new is very little difference in cost. Having it all out so we could make decisions was worth the few minutes.
Obviously, a gas furnace still needs electricity to run the squirrel-cage fan, so I flipped the breaker for the furnace and disconnected it at the furnace end. I pushed the wire through the hole in the floor. Next, I disconnected the ground wire which the prior installer had connected to the gas line. While I would like to accept that this was safe, it really didn't feel like it. I think we will run a fresh 3-wire line if we reuse this furnace. Since an electric furnace requires 220V, that would also get a new line.
Gas
gas and electric shutoffs |
Considerations
We have a curious cat, so we are leaving the furnace pretty much where it was while we figure things out. Otherwise, we would have a cat stuck in the heat system as fast as you can ask "where'd the cat go". Meanwhile we have some things to figure out. The furnace was manufactured in August 2019. The house was vacated around a year later, so the folks who installed the furnace got one winter out of it. We bought the place last year and used it this past winter so this furnace has 2 years of use. There are at least 15 more in it. Knowing that natural gas prices will continue to climb, eventually this furnace will be more expensive to run on a month-to-month basis than an electrical one, but that isn't the case today. Today, a gas furnace is considerably less expensive to run. A heat pump is different, but we don't have one of those. Adding a heat pump to this system would be a $8-10k upgrade. We are not in a financial place to do that. Assuming either system can reuse the existing hot side, and routing the cold return from the hole in the floor will be effectively the same, we can eliminate those from the decision: its a wash.
August 2019 |
Well, that's it for now. thanks, as always, for following along-