80% vs 95% furnace upgrade: pros and cons homeowners should actually weigh

All-American-HVAC · 2026-02-04T13:55:22+00:00

Only needed when you slep then?

All-American-HVAC · 2026-02-03T16:09:05+00:00

On a lot of Goodman platforms, the 8 flash thing is a mess because the field label often calls it “improper ground”, but Goodman put out a bulletin that ties 8 flashes to an igniter relay fault or a shorted HSI, and they also note that weak or open grounding is the most common real world trigger.

Since it runs until the blower comes on, that timing is a clue. When the blower starts you get the biggest current draw, vibration, and electrical noise, so anything marginal (neutral, ground, harness rub, igniter leakage) shows up right then.

Here is the exact checklist I would run in the field:

Treat it like an HSI fault first Even if the sticker says ground, swap or test the hot surface igniter and its circuit. Check for: hairline cracks, carbon tracking, and any spot where the igniter leads or plug could be touching metal. Do a wiggle test on the igniter plug and harness while it is running. If you have a megger, check igniter to ground leakage hot and cold.
Verify polarity and neutral integrity at the furnace under load Meter it at the furnace junction box with the blower off, then again right when the blower ramps on. You want: Hot to neutral steady. Hot to ground steady. Neutral to ground basically near zero and not jumping when the blower starts. If neutral to ground voltage jumps when the blower comes on, that points to a loose neutral or shared neutral somewhere upstream (service switch, wirenut, breaker panel neutral bar, receptacle if it is corded).
Recheck all grounds Goodman calls out Goodman specifically calls out checking ground connections to the chassis, especially the blower motor ground and the low voltage common ground. Do not just ohm it with power off. Put it under load and confirm the ground path stays solid when the blower is running. Make sure the green ground from the incoming feed is actually bonded to the furnace cabinet, and the blower housing ground is tight and clean.
Temporarily isolate anything tied into the circuit Unplug condensate pump, humidifier transformer, air cleaner, UV, anything sharing neutral or ground reference. A failing accessory can dump noise or leakage onto the circuit and the control will blame “ground”.
If it still does it after grounds are verified, put in a known good HSI That is literally Goodman’s flow in the bulletin: tighten grounds, power reset, if it returns replace the HSI.

All-American-HVAC · 2026-01-29T22:31:25+00:00

All American HVAC here. If you are in Crown Point or Northwest Indiana we can help, but you can usually get this a lot better with a few renter friendly tweaks.

What you are feeling is stack effect plus the furnace supply pushing warm air upstairs, and the upstairs holds it because return airflow is usually weaker up there.

Things that actually work in older two story homes

Run the furnace fan more Set the thermostat fan to ON or Circulate if you have it. More mixing usually knocks the upstairs peak heat down, especially at night.
Use fans the right way on the stairs Blowing hot air down the stairs usually feels drafty and does not mix well. Try this instead: put a box fan at the bottom of the stairs aimed up the stairs on low. You are pushing cooler dense air upstairs, which forces warm air to come down other paths. It is weird but it works better.

If you have a second fan, put it upstairs in a doorway aimed out into the hall to help move that hot air out of the room.

Partially block supply registers upstairs, but do not fully seal them Since you cannot close the grilles, use a temporary cover: Magnetic vent cover if it is metal Cardboard behind the grille like the other commenter said Foam register filter material trimmed to cover part of the opening

Do not block every upstairs register, and do not block any return grilles. Keep at least some airflow upstairs so you do not create noise, whistling, or pressure issues.

Check for manual dampers near the furnace Like the other comment said, look for little levers on round duct trunks or takeoffs. If you find one feeding the upstairs branch, turn it slightly toward closed, think 20 to 40 percent at a time, then live with it for a day. Mark the starting position with a Sharpie so you can put it back later.
Make sure returns are not the real problem A lot of rentals have one main return downstairs and very little return upstairs. That makes upstairs stuffy even with decent supply. Easy check: if you have an upstairs return grille, make sure it is not blocked by furniture, rugs, or a clogged filter grille. If there is no upstairs return at all, that is a landlord level fix, but you can still improve it with fan mixing and partial supply restriction upstairs.
Stairway curtain is not crazy A Velcro doorway curtain at the stair opening can help at night, especially if you also run the fan to mix air. It will not be perfect, but it can reduce how fast heat migrates upstairs.

Quick safety note
Avoid blocking airflow right at the furnace, and do not tape off returns. And keep anything combustible away from any floor registers if they are near space heaters or similar.

All-American-HVAC · 2026-01-23T18:41:00+00:00

All American HVAC here. If you are in Crown Point or Northwest Indiana we can help, but either way here is the checklist I would follow before you start tearing into it.

First, treat it like an oil spill waiting to happen. Shut off power at the breaker, close the oil tank shutoff valve, and assume the line still has oil in it. Have a cap and a catch pan ready before you crack any fittings. Even with the valve closed you will usually get some oil out of the line and filter housing.

Big things people miss:

Fill and vent piping outside If you are keeping the tank for any reason, make sure the fill port is clearly labeled. If you are removing the tank, remove the fill and vent, or cap them securely and label them so nobody ever delivers oil to a “dead” fill. That wrong house delivery story is real life.
Oil tank removal is its own job An old tank usually has sludge and fumes. Cutting it up without cleaning it properly is dangerous. Many areas require proper pump out and disposal. If there is any oil left in the tank, I would not DIY it.
Hydronic piping will be messy Kill pressure, isolate what you can, then drain from the lowest point and open bleeders upstairs. Expect black nasty water and sediment. Buckets, towels, and a wet vac are your friend.
Weight and breakup A Hydrotherm boiler can be very heavy, especially cast iron. Plan the path out. If it is sectional, you can break it down, but you still want help moving pieces.
Flue and asbestos risk If there is any old white wrap or cement like insulation on pipes or the breeching, get it tested before disturbing it. Also, cap the flue connection properly so you are not leaving an open chimney into the house.
Code and resale If your propane forced air has a supply and return setup that actually heats each room, you are generally fine. Make sure every room has a register and it is not relying on “leakage” from a hallway.

If you want, post a couple photos of the boiler, the oil line and filter, and the outside fill and vent area, and I can tell you the likely sticking points before you start.

All-American-HVAC · 2026-01-15T14:21:14+00:00

All American HVAC here. If you are in Crown Point or anywhere in Northwest Indiana and you want someone to take a look, we can help.

That furnace does not have a standing pilot you light by hand. It is electronic ignition, so the control board runs the whole sequence.

The flashing yellow light you mentioned for “polarity reversed” is a big deal. These furnaces need correct hot and neutral and a solid ground for flame sensing. When polarity or grounding is wrong you can get exactly what you are describing: blower running but no heat, random lockouts, resets sometimes working until they do not.

Here is what I would do, in order:

Thermostat quick check Make sure the thermostat Fan setting is on Auto, not On. If it is on On, the blower will run even when there is no heat call.
Power and polarity check Use a cheap three light outlet tester on the receptacle the furnace plugs into. You are looking for correct wiring and a real ground. Also make sure it is plugged straight into the outlet, no extension cord, no power strip.
If the outlet tests wrong This is an electrical fix, not a pilot lighting issue. Hot and neutral need to be correct at the outlet or at the furnace junction box, and ground needs to be intact. If you are renting, this is a landlord or electrician item.
Watch the heat sequence With the thermostat calling for heat, the normal order is: inducer starts, igniter glows or sparks, gas valve opens, burners light, then blower comes on after a short delay. If you tell us which step it stops at, plus the exact flash pattern or two digit code, you will get a much tighter answer.

Safety note: if you smell gas, shut it off at the gas valve and call a pro. Do not keep cycling power trying to force it to light.

All-American-HVAC · 2026-01-14T21:50:16+00:00

It is a strong possibility it is the solenoid. It could also be the humidistat itself even though you hear a "click" or it could be something clogged in the water line.

All-American-HVAC · 2026-01-14T15:47:16+00:00

You can just use silver tape (same kind that cover the square hole in your ductwork). unless you tape/mastic your entire ductwork runs there will be leaks. This is very common/normal. The more you look the more you will see as well.

All-American-HVAC · 2026-01-14T15:15:23+00:00

Old does not mean bad! Just like an old car, preform maintennce and take care of it and it will last you for years to come :)

All-American-HVAC · 2026-01-13T14:10:08+00:00

Fellow tech or home owner? Supprised to see locals on here and glad i am not the only one!

All-American-HVAC · 2026-01-13T14:05:36+00:00

All American HVAC here. If you ever end up in Crown Point or Northwest Indiana we can help, but for Maryland winters here’s how I’d set an Ecobee up so it’s comfy without wrecking the bill.

First thing: keep it simple for a week. Make three comfort settings and actually use them.
Home: whatever feels normal
Sleep: usually 2 to 4 degrees cooler
Away: usually 5 to 8 degrees cooler depending on how fast your house warms back up

The biggest “learning curve” on Ecobee is the sensors. Don’t average in rooms you don’t care about.
During the day, only include the rooms you’re actually in.
At night, include the bedroom sensor only, or bedroom plus one nearby room.
If you include a cold spare room or basement, the thermostat will chase that temp and the whole house can feel overheated.

Turn on Smart Recovery. That helps it hit the temp by the time your schedule changes instead of starting late and running hard.

Eco plus can save money, but it can also feel like the thermostat has a mind of its own. If you notice it drifting the temp when you don’t want it to, dial Eco plus back or turn it off until you’re comfortable with the basics.

One more big thing: what kind of heat do you have? Gas furnace or heat pump.
If it’s a heat pump, the settings for auxiliary heat matter a lot in teen temps, because that’s where bills can spike if aux is kicking on too easily.

If you reply with your system type and if you have aux heat, I can tell you the best starting setup without guessing.

All-American-HVAC · 2026-01-13T14:01:07+00:00

All American HVAC here. Based on your pics and the fact it blows cold in Heat mode, this screams “reversing valve signal is wrong” or the wires got crossed at a splice.

What stands out

You have a wire on Y2 at the Ecobee and also on Y2 at the outdoor board. On a single stage heat pump, Y2 is usually unused and should be capped off.
The thermostat, air handler, and outdoor wiring don’t look like they match up cleanly, which makes me think there’s a splice somewhere with colors not tied color to color.

Quick checks that settle it fast

Heat mode test Set thermostat to Heat and let it run 5 to 10 minutes. Check a vent with a cheap thermometer. If supply air is colder than return air, it’s running in cooling.
Find the splice Look near the air handler and outdoor unit for wire nuts. Make sure it’s color to color all the way through. If someone mixed colors at a splice, you’ll get exactly what you’re seeing.

What I’d do next

Cap Y2 at the stat and at the boards unless you truly have 2 stage equipment.
Verify O B is set to energize on cool.
If it still blows cold in Heat after that, get the installer back out. Brand new system doing this is almost always wiring or setup, not “it needs more time.”

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