Tried to plug my furnace into my solar.

[400bird]

NC_hydro
(No, I'm not trolling you).

I'll have to post a picture...I think I grounded the 2000watt pure sine inverter.

Despite your previous disclaimer, I'm still picturing something like this:

 

[JWLV]

When I grounded my inverter, I told it, "No more power for 2 weeks mister!"

 

[hwy17]

I can't imagine how or why a furnace would be "checking" for a ground. I have never in my experience come across any electrical appliance that does this.

My guess is the inverter is failing to support the heavy load of the probably resistive igniter.

Check the output voltage while it's under load and the furnace is supposed to be trying to light.

 

[zanydroid]

I can't imagine how or why a furnace would be "checking" for a ground. I have never in my experience come across any electrical appliance that does this.

My guess is the inverter is failing to support the heavy load of the probably resistive igniter.

Check the output voltage while it's under load and the furnace is supposed to be trying to light.

Furnace is one of three appliance types I can think of that check for or assume there is a N-G bond, besides:

EVSE
UPS

 

[hwy17]

Furnace is one of three appliance types I can think of that check for or assume there is a N-G bond, besides:

EVSE
UPS

Well, I'm open to being ignorant on it if furnaces really are part of a tiny subset of appliances where this is a thing. I don't have a furnace.

 

[hwy17]

Yeah I see now, it's a reverse polarity check that needs the ground reference to determine the polarity.

 

[Supervstech]

I can't imagine how or why a furnace would be "checking" for a ground. I have never in my experience come across any electrical appliance that does this.

My guess is the inverter is failing to support the heavy load of the probably resistive igniter.

Check the output voltage while it's under load and the furnace is supposed to be trying to light.

The flame confirmation circuit uses a micro volt signal it detects as it passes through the flame. The circuit board uses the ground to neutral connection to pass through. If it isn’t bonded, then it gets crazy voltage variation, and refuses to give signal for fuel to flow.

 

[hwy17]

The flame confirmation circuit uses a micro volt signal it detects as it passes through the flame. The circuit board uses the ground to neutral connection to pass through. If it isn’t bonded, then it gets crazy voltage variation, and refuses to give signal for fuel to flow.

I would be curious then to understand if this is was a technical necessity for the function of the flame rectifier, or some particular safety necessity. AC is nonpolar of course so I don't see how it technically couldn't just reference itself on the designated neutral neutral side irrespective of whether there is or isn't a reversal, but I guess there are multiple possible safety reasons why they would decide that wouldn't be acceptable.

 

[Supervstech]

The circuit is looking for a SPECIFIC mv result, so unbonded to neutral, the reference would be all over

 

[400bird]

I would be curious then to understand if this is was a technical necessity for the function of the flame rectifier, or some particular safety necessity.

I don't think it's a technical necessity. My gas dryer just uses a light sensor to know when the ignitor is hot and to open the gas valve.

 

[hwy17]

I don't think it's a technical necessity. My gas dryer just uses a light sensor to know when the ignitor is hot and to open the gas valve.

Yeah lol. The last gas dryer I fixed used a literal tensioned bimetallic strip that would click when it got hot enough and it's running great for 5 years after I replaced that $7 part. I'm getting a bit schooled in the fact that furnaces were apparently not allowed to continue that way even into the 90's.

 

[hwy17]

The circuit is looking for a SPECIFIC mv result, so unbonded to neutral, the reference would be all over

Yes but couldn't it just reference neutral in an isolated capacity, and then it wouldn't technically matter if hot and neutral were reversed it would just reference hot, which would work because AC has no polarity. So it seems like at some point there would have to be some ancillary safety reason to decide to ground or ground or ground reference anything.

Anyway, I should probably just back off the subject because I don't have a furnace and don't intend to, so I'll leave it to you furnace experts.

 

[Supervstech]

Yes but couldn't it just reference neutral in an isolated capacity, and then it wouldn't technically matter if hot and neutral were reversed it would just reference hot, which would work because AC has no polarity. So it seems like at some point there would have to be some ancillary safety reason to decide to ground or ground or ground reference anything.

Anyway, I should probably just back off the subject because I don't have a furnace and don't intend to, so I'll leave it to you furnace experts.

Well, the mv signal flows through the grounded chassis to the signal probe, through the flame. So this type of ignition verification references the neutral to ground signal.

 

[hafbakd]

No! No! No! No! No!
Please, don't ever think that again. 12v is NOT short form for 120v. And 24v is NOT short form for 240v.

12v generally means 12 volt DC such as commonly used in car batteries, although there are some devices that use 12v AC. It's rare to see anything that uses 12v AC. Some door bells are powered by 12v-24v AC (not DC). 120v is generally 120 volt AC, such as your home's wall outlet. AC and DC are two different things. 12v and 120v are two different things. You cannot mix and match and hope for it to work.

only VERY OLD cars use (6V DC or) 12v DC except perhaps for charging. all modern cars use ALTERNATORS that provide ALTERNATING CURRENT

 

[hafbakd]

LakeHouse
I don't know what it means to ground the inverter.
Of the dozens of tiny homes and van life + google search research I've done;
Panels are plugged into the mppt controller.
Batteries are plugged into the controller.
Batteries are plugged in parallel (red to red to red. Black to black to black).
They are plugged into the inverter (via black and red plugs in the back).

I've got a power bar plugged into the inverter with a bunch of extension cords coming out of it.
1 for an outlet in the kitchen (for small appliances)
1 for the washing machine
1 for the fridge
1 for the living room (tv, laptop, stereo).

Not all at once. We kinda rotate through the week.

As far as grounding the inverter...no.
There's nothing plugged into the ground pin at the back.

hafbakd
As far as a surprise explosion is concerned.
I tested it out with a gas generator (champion 4450), plugged in with a 100 foot 3 prong extension cord, from the shed to the basement. It worked.
I only ran it for 10 minutes, because the generator is loud, even in the shed).


42OhmsPA
please edit your post to clarify 12V vs 120V.

(I thought 12v was a short form for 120v, like 24v is a short form for 240).


To group a response to the rest of the comments;
I hoped the furnace would fire up with a jolt of power, but once the gas was burned, I hoped the endurance part of the solar system was going to power the fan and keep the house warm.

I can accept if the furnace is defecting an inadequate power source.
My question is, why would the gas generator do it with a 3 prong extension cord, but my solar set up, with a 3 prong extension cord won't fire it up?

cuz the gen is sending ADEQUATE AC to the furnace but YOUR SOLAR HARDWARE ISN'T

 

[Supervstech]

only VERY OLD cars use (6V DC or) 12v DC except perhaps for charging. all modern cars use ALTERNATORS that provide ALTERNATING CURRENT

Nope...
The alternator makes alternating current, but thw diode pack converts it to DC before it leaves the case...

 

[Supervstech]

cuz the gen is sending ADEQUATE AC to the furnace but YOUR SOLAR HARDWARE ISN'T

Nope again... current is fine, lack of bonded neutral to ground is the issue.

 

[400bird]

cuz the gen is sending ADEQUATE AC to the furnace but YOUR SOLAR HARDWARE ISN'T

Wut? This doesn't make sense at all

 

[SparkyJJO]

only VERY OLD cars use (6V DC or) 12v DC except perhaps for charging. all modern cars use ALTERNATORS that provide ALTERNATING CURRENT

Internally to the alternator yes, but it is converted ro DC before being connected to the car's electrical system.

Can't connect AC directly to a 12V DC car battery now can you?

.... have you worked on a car before?

 

[OffGridForGood]

I've got an EAsun 80v mttp controller. A 2000 watt pure sine inverter.

Which Inverter do you have?
Some Inverters make an internal N-G bond while they are invertering.
However many small inverters do not form this bond.
When we say "Bond" we mean connection: The Neutral terminal is electrically connected to the Ground terminal - and as the guys say In ONE place, and only one place.
The reason a typical portable generator will work is because inside the generator wiring they put a jumper wire (a wire) connected from Neutral to Ground. This is because without that jumper (wire) the generator operating on it's own (not part of a house electrical system) would have NO Neutral-Ground bond.
Now Guys - OP is new to electricity and clearly not sure of the lingo and terminology, lets focus on exactly what he needs to tell/show us so we can help him get the furnace to operate. He says he can get the fan to run - that means to me he has enough power to supply the motor in-rush, and should - with proper N-G (neutral to ground) bond be able to get the ignition system to function as well.
So, Which inverter do you have, show us a picture of that inverter and how it is set up. If your furnace is plugged in with a three prong plug, but the Neutral and Ground have no connection (no bond) anywhere, the ignition system will fail.