I have a day and night high efficiency furnas. The forced induction fan comes on then quits. Sometimes it will stay on long enough for the ignitor to light then everything quits. I used a volt meter on the pressure switches I have two. One of them doesn't receive the 24 volts. I have turn the power off the furnace overnight and when I turn it on everything works normal one time but the next time it is just like before. Could it be the cuircut board? Thanks

Quote:

---

Originally Posted by ardad

I have a day and night high efficiency furnas. The forced induction fan comes on then quits. Sometimes it will stay on long enough for the ignitor to light then everything quits. I used a volt meter on the pressure switches I have two. One of them doesnt recieve the 24 volts. I have turn the power off of the furnace overnight and when I turn it on everything works normal one time but the next time it is just like before. Could it be the cuircut board? Thanks

---

Try this first. Clean the flame sensor. Do not mess with the ignitor.

Quote:

---

Originally Posted by hvac1000

Try this first. Clean the flame sensor. Do not mess with the ignitor.

---

I did that, most of the time I never get to where I have a flame.

Then you will have to start testing components. You say the inducer fan will start then stop. Why? Did you check if the circuit board stopped producing voltage for the fan or is the fan motor itself defective? You need to test to be sure what is the problem before you start replacing parts.

Quote:

---

Originally Posted by hvac1000

Then you will have to start testing components. You say the inducer fan will start then stop. Why? Did you check if the circuit board stopped producing voltage for the fan or is the fan motor itself defective? You need to test to be sure what is the problem before you start replacing parts.

---

The ciruit board stopped producing voltage to the inducer fan.

Then I guess the board is bad.

Quote:

---

Originally Posted by ardad

The ciruit board stopped producing voltage to the inducer fan.

---

That's pretty definitive to be your board. Just to be sure, check the input voltage to the board that's passed through to the inducer fan.