Bryant Furnace Relay Clicking

Paul2021

I have a Bryant/Day & Night/Payne model 395B from the 80s. Intermittently, it would fail to restart. When that happens, some relay would click as shown here: https://youtu.be/kizyBcWPrBQ

I have changed the main control board and the gas valve. But the problem persists.

If I manually turn the furnace off and on again, it sometimes would not start. When it fails to start, the induction motor would often move by a tiny step, then nothing happens. It typically takes a few on-off toggles to get it going. Once started, it would run OK until at some point it fails to restart, and the clicking starts.

HVACNUT

Can you post a pic of the wiring diagram?
Do you have enough money left for an electrical meter?

mattmia2

who adjusted the gas valve after you replaced it?

i assume you jumpered r-w before parts changing to rule out a bad t-stat or wiring

and traced the power from the transformer to the gas valve or at least the control board on both sides. sounds like a loose connection somewhere, either the t-stat or the power from the transformer or possibly the contacts in one of the safeties

that sounds like what you'd get if you intermittently touched a wire to the power source or the t-stat wires together

EBEBRATT-Ed

Shooting the parts cannon at it is not the answer. You need a test meter

Jamie Hall

Without a test meter you're just guessing. You might get lucky and hit the bad part or the bad connection, but more likely not.

Using the circuit diagram, check all your voltages everywhere -- including the moto start and run windings and the caps.

HomerJSmith

Why not shed a little light on the subject? What is the blue light ? Maybe it is the sparking of the spark electrode? Maybe the pilot orifice is not fully open and gas isn't getting to the spark.