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BillyHvac
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22311
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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I'm replacing a Honeywell ST9160 with SV9520 Smart Valve

Customer Question

I'm replacing a Honeywell ST9160 with SV9520 Smart Valve with a Honeywell ST9120B,U. In my original book it showed neutral 2 going somewhere and then nothing comes back to the control board on the hum spot my book also shows a line on neutral 3 but i have nothing.
Im quite lost
Submitted: 1 month ago.
Category: HVAC
Expert:  BillyHvac replied 1 month ago.

I know you probably already have it...but here is how the 9160 transfers to your 9120b

click here

As far as HUM..that is an accessory for a humidifier.

The neutrals are all the same and do not matter which is used by what as long as they are neutrals.

If you tell me specifically what wires you have a problem with I can help

Billy

Customer: replied 1 month ago.
Your link doesn't open, is it just the schematic in the book?Okay the HEAT wire makes sense into HEAT
The COOL into COOLI was confused about M1 & M2 But i think those go into UnUsedIf you say all that go into neutral doesn't matter then that makes it a little easierthe COM snd 24VAC i am a little unsure of but if I follow the schematics lines and keep the wires in line into the transformer snd back out then those go into C & XL1 im not sure about i don't think
Customer: replied 1 month ago.
the white w/ blue collar i was not sure about but if you say all neutrals go into either neutral thats okay and same with the white with no silver collar
Expert:  BillyHvac replied 1 month ago.

see page 3 here

Give me a moment and I will do a crossover for you

Expert:  BillyHvac replied 1 month ago.

try this one more time...if it doesnt work I will write it out

click here

Customer: replied 1 month ago.
for L1 as long as i keep them straight vs which got into the transformer I'm okay right?
Customer: replied 1 month ago.
i need that jumper in too correct?
Expert:  BillyHvac replied 1 month ago.

correct

the confusing ones are:

24vac =X

COM= C

m1=unused

m2=unused

and yes on the jumper plug

Customer: replied 1 month ago.
how do I tell 24VAC apart from COM
Customer: replied 1 month ago.
does It matter which one of the L1 goes up to the transformer and which is the black wire w/ blue collar
Expert:  BillyHvac replied 1 month ago.

the transformer has 4 wires..black and white on the 120v side.

black is located next to L1 as that is where it gets 120v to supply transformer. White goes to any neutral

The wires on the 24v side depend on if it is original transformer for color...what are the colors of the 24v wires from trans?

Expert:  BillyHvac replied 1 month ago.

and what is furnace model number so I can check color code

Customer: replied 1 month ago.
armstrong air ultra 5 okay turned it on i hear a beep and the control board flashes 4 then solid for a second
Customer: replied 1 month ago.
i get a steady hearteat on the gas valve
Expert:  BillyHvac replied 1 month ago.

when this all started...was it because the blower did not run?

Customer: replied 1 month ago.
the furnace was doing all sorts of issues not firing not running long enough we had a tech out and of course when we did it worked fine since until yesterday he told us last time to replace the control board which is where i am now
Customer: replied 1 month ago.
he checked everything else when it was running and said it looked okay when i just turned on the furnace now like i said it whines from the control board. and flashes 4 times here is everything wired
Expert:  BillyHvac replied 1 month ago.

page 23 here will show your colors

looks like blue is 24vac and yellow is com

is the main blower running ?

Customer: replied 1 month ago.
both my com and 24vac are yellow no nothing ran when I turned it on - the whine and 4 flash makes me think an error?
Expert:  BillyHvac replied 1 month ago.

I do not see a wire on IND? Should be a black wire from exhaust motor

Customer: replied 1 month ago.
what would that have come out of on my original board? ill send that now too
Expert:  BillyHvac replied 1 month ago.

follow the wires from the exhaust motor.....tell me where they currently are

Customer: replied 1 month ago.
okay from the bunch of cables the red goes to heat black to cool blue and yellow to unused and a white into neutral if the exhaust is the top one? there are some purple that go down to the gas valve area
Expert:  BillyHvac replied 1 month ago.

ok the exhaust fan down by gas valve.....has a black and white wire going into it...I cannot trace it in the pic...where does that black and white go?

Customer: replied 1 month ago.
okay two black wires come out of the motor into two pin connector which turns into black and white which run into the back of the gas valve
Customer: replied 1 month ago.
on the wiring diagram it doesn't show anything supposed to be on IND?
Expert:  BillyHvac replied 1 month ago.

thank you,

Now all wires appear right....also coming from the gas valve will be a couple wires that go to temperature safety switches.

By chance did your tech tell you that on this particular furnace the gas smart valve is most often the issue?

This is known as a honeywell smartvalve that failed in great numbers and was dropped

Customer: replied 1 month ago.
we had an issue previously with the valve snd it was replaced the valve has a solid heartbeat on the LED although I'm told that doesn't mean much does the whine / 4 flashes concern you? should i turn on the furnace and cycle the thermostat?
Expert:  BillyHvac replied 1 month ago.

before we start...try swapping the yellow wires from the transformer...

Customer: replied 1 month ago.
okay i'll do that and see if the result is different
Customer: replied 1 month ago.
okay swapped them and the same thing the board whines snd it flashes 4 times and on the 5th i solid for a second
Expert:  BillyHvac replied 1 month ago.

it is reading a open limit, but if the limit is open a blower should be running.

Try the thermostat for a cycle...

Customer: replied 1 month ago.
cycled down thermostat clicked off heat turn it up clicked to heat and nothing - no sound no movement
Expert:  BillyHvac replied 1 month ago.

the 2 black wires at L1....which goes to the door switch?

Customer: replied 1 month ago.
the left one goes to the door switch - i tried switching them it didn't change anything
Expert:  BillyHvac replied 1 month ago.

ok last checks...

on new board under the plug..what are those terminals labeled..They have 2 yellow wires right now.

Then above by other plug are 2 wires...blue and yellow...what are they labeled

Expert:  BillyHvac replied 1 month ago.

the blue and yellow unused?

and the 2 yellows C and X?

Customer: replied 1 month ago.
thats correct the blue and yellow are unused which came from M1 & M2 on the old board and the bottom 2 are the C & X which come from the transformer
Expert:  BillyHvac replied 1 month ago.

I am afraid thats all I can do from this venue...everything looks correct at this point.

I am going to open this to the others for a look for more opinions..

Billy

Customer: replied 1 month ago.
Just to update
Switched door switch and other wire back around turned furnace back on got steady heart beat on control board. But sadly no heat with cycle of thermostat. Furnace sat silent

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