oil heat gurus

[70bigblockdodge]

In the shop. Two words "hot wire"

Safety

 

[eldubb440]

flame eye works......I even made it turn the little green light on and off

I mimicked a "call to heat" and got zero voltage to neither the "motor" nor the "ignitor" tabs on the controller.......power in, but not out

headed out to buy a controller.....

 

[eldubb440]

In the shop. Two words "hot wire"

Safety

at this point, yes, I could rig it to run....... but I wont, at least not yet

 

[eldubb440]

ok.....I'm pulling my pudd ..... to a point

the new controller didnt fix it, but it's the updated model with diagnostics..... ok

it says the limit is open, and needs to be closed.......

I see no limit switch...... just a sensor, with 2 wires to the circuit board.......there are relays on the board, do these serve as the limit switch?

the sensor has continuity

the relays are soldered on, not serviceable....... if the "limit" is within the board, it's only 60 bucks or so

 

[RemCharger]

Can you see the back side of the old circuit board?
Resoldering relay joints etc is a common repair. A pic if you can

 

[Don Frelier]

The 120 volt power from your breaker should go to a high limit temperature switch and then supply power to the burner control.
It's a normally closed switch which opens on temperature rise.
Recheck your connections maybe just a bad wirenut connection or something.
The high temperature cutout would almost never be a point of failure.

 

[hunt2elk]

Without seeing a pic of what you have going on, I'm going to guess. You need to tie the black "L1" and red "limit" wires together on the back of the control. These 2 go to your power supply hot. I personally have never seen a unit that needed the red wire tied by itself to a limit switch.

 

[Don Frelier]

Without seeing a pic of what you have going on, I'm going to guess. You need to tie the black "L1" and red "limit" wires together on the back of the control. These 2 go to your power supply hot. I personally have never seen a unit that needed the red wire tied by itself to a limit switch.

Maybe it's your wording, but it sounds like your suggesting bypassing the high limit?

 

[eldubb440]

Without seeing a pic of what you have going on, I'm going to guess. You need to tie the black "L1" and red "limit" wires together on the back of the control. These 2 go to your power supply hot. I personally have never seen a unit that needed the red wire tied by itself to a limit switch.

this is the old unit........ there is no tab where it says "limit"

the new unit is a direct replacement as it says on the box, it replaces several....... and it DOES have a "limit" tab

 

[Don Frelier]

The older style were powered by the high limit switch.

The newer ones are powered right from the breaker and take the high limit switch as an input.
So not really a direct replacement. You need to find where the high limit is powered and the wire coming back from the switch.
Shouldn't be too hard.
High limit goes in above the fire chamber.
But don't confuse it with the fan limit switch.

 

[eldubb440]

back of the new controller...... has the "limit" tab

 

[eldubb440]

You need to find where the high limit is powered and the wire coming back from the switch.
Shouldn't be too hard.
High limit goes in above the fire chamber.
But don't confuse it with the fan limit switch.

see above......

I don't see any "switches", therefore no wire

that's why I am asking if the relays on the board do the switching?

 

[eldubb440]

 

[eldubb440]

Overview​

ST9103A integrates control of burner and circulating fan operations in an oil furnace.

Features​

• Central appliance wiring point simplifies service
• Oil burner primary control
• Fixed or field-adjustable heat fan on delay
• Field adjustable heat fan off delay
• Controls two speed circulating fan

Product Specifications​

ApplicationA single circuit board providing combustion air blower control, two speed circulating air blower control, oil primary control, limit circuit inputs, thermostat wiring terminations, & a central appliance wiring point for an oil fixed furnace.Frequency50 Hz; 60 HzApprovals, Underwriters Laboratories Inc.Listed: Report MP466Approvals, Canadian Standards AssociationCertified: File No. LR95329-17Ambient Temperature Range (C)-40 C to +66 CAmbient Temperature Range (F)-40 F to +150 FReplacesST9103A1002Heat Fan On Delayfixed, 45 secHeat Fan Off Delayadj. 60, 90, 120, 150 sec (set at 150 sec)Cool Fan On Delayfixed 0 secCool Fan Off Delayfixed 0 sec

 

[hunt2elk]

Look at the instructions with the new control. It will tell you to add a wire to the red "limit" and tie that to the L1. That is all you have to do. Your old control didn't use that feature either. Your high limit switch is either in series with the power wire already, or tied into the other circuit board.

 

[Don Frelier]

Pretty sure the object highlighted here with the yellow box is your burner high limit switch.
But I can't tell where the wires go in your existing controller.
Schematic shows below in yellow.
If the wires from that switch match what I've shown below you need one connected to L1 (120V) and the other back to the limit terminal on the burner control.

Note that your existing controller controls the fan speed as well.
So if you modify the wiring you may want to consider putting it back into the original style board some day.
You can test the limit control by disabling the fan and running the unit (don't do it too long).
But the burner should kick off when the chamber gets above the high limit.

 

[hunt2elk]

View attachment 1602613
Pretty sure the object highlighted here with the yellow box is your burner high limit switch.
But I can't tell where the wires go in your existing controller.
Schematic shows below in yellow.
If the wires from that switch match what I've shown below you need one connected to L1 (120V) and the other back to the limit terminal on the burner control.
View attachment 1602618
Note that your existing controller controls the fan speed as well.
So if you modify the wiring you may want to consider putting it back into the original style board some day.
You can test the limit control by disabling the fan and running the unit (don't do it too long).
But the burner should kick off when the chamber gets above the high limit.

The high limit switch you drew a box around is already wired in. The new control he bought is a replacement for what he had. I will say it one more time and am then I'm out. In the box with the new control will be a red wire. Stab the one end to "limit" on the back of the control. Wirenut this red to the black "L1" wire and the black power wire. Don, you are making this way to difficult. No need to rewire anything....

 

[eldubb440]

The high limit switch you drew a box around is already wired in. The new control he bought is a replacement for what he had. I will say it one more time and am then I'm out. In the box with the new control will be a red wire. Stab the one end to "limit" on the back of the control. Wirenut this red to the black "L1" wire and the black power wire. Don, you are making this way to difficult. No need to rewire anything....

lol..... I'm gonna do as you suggest...... and Don agrees....... I was in no way ignoring good advice...... and thank you...... I will report back

 

[1 Wild R/T]

 

[eldubb440]

wife cooked for me, didn't eat all day..... and a couple other random distractions..... headed out there in a few minutes