Wall Furnace

I had to splice the yellow Power Pile wire with 12 gauge wire because the correct crimp fitting had been changed for some reason to a male fitting when it actually GOES to a male fitting. So, that didn't work and it was too short to snip and put a new terminal on that wire, so I spliced two Female terminals on there.

 This mess is the wiring for the cozy wall furnace valve. This is older so it is basic. I'm not saying how I wired it is right, but it works. I had some trouble because I removed the critical overheat wire from the TH-PP terminal and misjudged where I got it from so I put it back in the TH terminal with the thermostat wire. My older notes did suggest this is how it was wired but it didn't work. This led to the pilot light working but the thermostat would not engage the burner. I battled it and you can see that the diagram in the manual sort of blurs where the hell the connections are for the power pile is. In fact, you can't even see where the power pile is in the diagram but it's in the lower left corner...it has a yellow wire coming from the center of a threaded unit in one photo where I had to identify what it is. That wire doesn't wander off to the left. No, it is terminated like in the unit on the right with the red wire that goes to the TH-PP terminal. That's the Power Pile.

So, the TH-PP terminal gets a wire from the Power Pile, AND a wire from the Pilot Generator, which is sometimes called a thermocouple which actually generates 500 millivolts from the heat of the pilot light. Pretty clever! And that terminal gets an overheat/blocked flue wire too. Now, if they called that terminal the TH-PP-OH (for OverHeat) then I wouldn't have been confused. But they didn't and I messed up when I put it all back together.

The TH terminal gets exactly one THermostat wire. This makes sense but also makes me wonder what the TH stands for in the TH-PP terminal that does NOT get a thermostat wire. I guess that TH means THermocouple, but am I the only one who thinks two different TH terminals that mean two different words is a mistake? Thermostat and Thermocouple...how am I supposed to know the top TH means Thermocouple? Especially when their own diagram calls it a Pilot Generator. Call it PG-PP. Right? Pilot Generator + Power Pile. Does that make too much sense? And the manual itself is not clear either. So, the terminal ID and the diagram are both crap. They figure only an experienced HVAC tech would wire this, but then they provide horrible diagrams? why bother? To tempt me into thinking I can do this myself. Like crimping lugs on wires is so hard?

The PP terminal gets exactly one pilot generator wire. Maybe the PP means Pilot Power? Maybe Pile Power.

That will still leave you with one Overheat/Blocked Flue wire and also one wire from the Thermostat. These two wires are connected with either a male/female crimp fitting, or just a wire nut.

As near as I can tell the overheat sensor is a normally closed circuit that will OPEN when it gets too hot. The Thermostat is a normally Open circuit that closes when the mercury blob (in my case) completes the circuit between the two wires.

The mini-split heater does generate heat and it keeps the room around 70 degrees, but I'm sitting here with blankets because a super dry 20% humidity and 70 degrees is not super comfortable. I'd prefer more like 75 and I'm not sure the split unit can get to 75 degrees. And even if it does, it will use electricity and wear down the unit, which is best saved for cooling in the summer. See? I had to decide if the wall furnace was going or staying and I decided it would stay. The minisplit also blows warm air out that kind of creates a draft I don't like. The furnace simply produces hot hot air that drifts through the room. It's superior heat.

So I sawed through the wall, connected new B style gas vent and then put the wall furnace back together since a wall exhaust exit with B vent is not so easy unless you cut a huge hole ,which I did not. I cut the minimal hole and there was no way to get the adjustable elbows through it and then back down onto the heat diverter where the gases exhaust from the furnace. So, I had to take the combustion chamber out with the heat diverter and then get the vent all situated and then put the combustion chamber and heat diverter UP INTO the stationary duct. It was a pain.

But it's all for the purpose of optimal heat in the house, using what I have, gas is cheap and the furnace worked all winter last year and I expect it to last this winter too. I could replace the valve but I treat the furnace like a temporary unit that I shut on and off each time I use it. I even turn the gas valve off, which I don't have to do since the valve on the furnace works, but the automatic shut off stopped working so I don't fully trust it. This means the pilot light comes on without having to depress the knob. Gas immediately goes to the pilot light when I turn the knob. I can tell no gas comes out when it's off, but is it such a big step to turn the hose valve off too? No, it's better to keep all the valves off, and when I want heat I turn both valves on, light the pilot light, turn the thermostat up, etc.

If this is confusing imagine how confused I was when I was looking at these wires.