How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask BillyHvac Your Own Question
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22513
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
Type Your HVAC Question Here...
BillyHvac is online now
A new question is answered every 9 seconds

are you there to answer my question to my issue concerning

This answer was rated:

are you there to answer my question to my issue concerning heat?

I answered to another one so if you get 2 disregard.

So you have no heat with a 8 flash code?


Customer: replied 3 years ago.

Sorry bout that...dont know why it was like that for over an hour but perhaps the problem was someone wanted to answer it and we wanted you...yes the problem is turn heat on and it comes on for a second while the light flashes two tmes then pauses and comes on solid,,,,the light, the furnance acts like it is going to actually kick on all the way since the tubes light up and then it instantly kicks off and flashes 8 times, pauses and flashes 8 times again...recall from previous that there was a new thermostat installed and then you told us that it was actually the control panel since the test you had us do led to this and then you told us how to bypass it so that we had ac if we manually turned it on and off, now with new control panel the a. c is good running without us doing it manual, but the issue listedabove is with the heat and heat is what we need


first thing.

Lets take doors off furnace and tape the door safety switch down.

Remove the thermostat wires from R, G, Y, W, etc.

Then turn furnace on and tell me if solid lght.


Customer: replied 3 years ago.

Heading there to now, door panel is already off so he is going to remove the wires....just a second please

Standing by...

Customer: replied 3 years ago.

yes light comes on

Thank you

Now with a short wire or jumper....carefully jump R to G first.

Tell me if blower runs and light stays solid.

Customer: replied 3 years ago.

just minute hooking up jumper...paper clip...

Take your time.

I am in no hurry so lets be careful and sure.

Customer: replied 3 years ago.

it kicked on flashed twice and then stayed constitnly ran til i turned the power switch off


remove R to G jumper.

Now put jumper R to W

Same thing...tell me code and what happens

Customer: replied 3 years ago.

r to g does this....kicks on stays solid and does so til i remove jumper with fan as well ...sorry redid to make sure this was correct and now r to w with jumper kicks on flash twice stays solid and runs til shuts of switch even if removed jumper it still did until shut off by main power

Do you know what the pressure switch is? Looks like size of hockey puck...has rubber tube from it...

Customer: replied 3 years ago.

what is it???switch u had me tape down? i doubt that is what you are talking about so tell me where this may be found....general area or so

Customer: replied 3 years ago.

i thnk there is two of these hockey pucks things as they both have a white rubber tube coming from them....and two wires on each as well...???

See page 5 HERE
Customer: replied 3 years ago.

ours has two,,,,one for each burner maybe?

This may get a bit involved so at any time let me know if you wish to backoff.

remove the wire to the pressure switch...either one...

Start unit and tell me if we get a 3 code

Customer: replied 3 years ago.

i unpluged a wire from one of the switches, and turned main power on and light stays solid....????

Customer: replied 3 years ago.

i also put the wire i unplugged back into the switch and unplugged the wire from the other hockey puck switch and the same thing happened when i turned on the power....the light stayed on solid

Ok...I think we have an air switch that is stuck closed. This confuses the circuit board.

Lets try this.

R to W jumper in place.
Power is off
wire removed from pressure switch

Turn power on
AFTER the exhaust fan kicks on plug the wire bacl on the pressure switch.

Tell me what happens and code
Customer: replied 3 years ago.

the furnace turned on.....when we r to w with jumper and then turned power on while jumper r to w and replaced the wire to the switch that looks like hockey puck, the light stayed solid and then we heard click and pilot cdame on burners ignited no code and since we have open flame so i took jumper off and turned power off since not sure what wanted me to continue to do....

THis worked though we had it on....

Thank you.

We have a stuck pressure switch.

One of the 2 switches is stuck in the closed position

Remove the tube to each and gently blow and draw air from there. Hook tubes up.

No jumper r to anything...

Thermostat as normal
Power on and try a heat cycle.

Customer: replied 3 years ago.

unhooked a grey tube that goes to the hockey puck or pressure switch and then blew in each one and put them back on do that i have to hook up the thermostat switches again correct? THen try to turn the heat on like i would if nothing ever was wrong? just blow threw each of them rbber tubes and hook it all up? just checking to make sure i follow correctly

Correct...but we need to blow and draw air from the will hear a click if you listen carefully. This is the microswitch inside that activates with air flow.

Do this to both switches listening for click...hook tubes back up

Start in normal use.

Customer: replied 3 years ago.

oh okay,,,give me second to hook it all bakc up and listen for the click when we blow and draw air doing either or both til isten for a click....just a minute or so

No proble, you see furnaces are not like they used to be...much more involved now.

Sometimes I think they just want to design them so folks have to call for service...

Customer: replied 3 years ago.

This all did not work it all came on just like before and shut off as before and then it gave the 8 flashes after it shut itslef off again...could the prob be the thermostat? When the problem was just the ac and the people came out thnking it was the thermostat and brought in a new one they were arguing about how it hooked up...also on the thermostat to the board on the furnace is there suposed to be a jumper going from c to y...on the actual furnace? thats the way it was wired...i dont know but there wil be a tip for the size fo the paymetn since this is five or free just ot let yu knwo we dont expect u to do allthis for nothing

Can you confirm how the thermostat is wired?

red to r
white to w
yellow to y
green to g

At no location at all should be a jumper of Y to C

Customer: replied 3 years ago.

going upstairs to look at the thermostat....was downstairs with the we go thanks so much this is alot esp online but its cold and im at my last straw here....need you to come out to our house...ha ha...

Dont worry...

The inconvenience is after I have you run up and down stairs a few times...

Customer: replied 3 years ago.

therm upstairs with it off goes red to r, yellow to yy2, and green wire to g, and white wire to the ww(this one is hard to read so if it has slash or number after it i cant tell nnot in color imprinted) my concern now is with the furnace when i took off the old contol module there was two wires coming off and the red goes to c and the white wire goes to y where the yellow wire goes as well this is what i was scalling the jumper to y to c...wanting you to understand that there is two wires coming off of one loom or hook up on the furnace control module

There will be 2 wires from the outdoor ac unit that (on control board) go to Y with a yellow from thermostat and the other to C. thermostat..remove the red wire and the white wire and twist together.

I am hoping the red is on R in the furnace and white is on the W.


Customer: replied 3 years ago.

ok at therm i twisted the red wire and white wire together and hcekced to make sure that on furnace the red is on r and the white is on the w....the above checks out as well regarding the issue on outdoor ac to the therm as well so now ????

With the r and w twisted together...and power on...what is operation and code on light?

Customer: replied 3 years ago.

when those two are together there is no code when i turn it on was running and stayin on no code....i turned off the pwoer on it and came back upstairs to type to you

So the unit is running normal now and heating with r and w connected at thermostat
Customer: replied 3 years ago.



One issue was a stuck pressure switch.
You freed that up and now it is functioning correctly.

The thermostat is not working as it should. We currently have it bypassed to make a connection between R and W which is what the thermostat do.

So...short story is we have fixed the pressure it is justa problem with the thermostat or it is programmed...but something is wrong in the thermostat.

Thank you so much for being patient with me. You can get heat anytime you want by twisting r and w but it will not shut off. I know you had work done with thermostat but it needs to be replaced...

Thanks again for hanging in there!

Customer: replied 3 years ago.

I cant believe that...but should go with gut huh? Even had we had pinpointed the thermostat as being messed up somewhere along the way we still would of had issue with the stuck pressure thank you so much and also the first time when you gave us relief with air by tellin us to replace the control module...funny how you can fix the problems that four men, professional supposedly, and you do it online! To bad we cant just contact you straight out when we have problems or have friends or family with problems as you really know what u are doing and we are very grateful and now warm too! Thanks for sticking in there with us esp we calling things hockey pucks haha

Even with thermostat issue you had that stuck switch...which can drive many batty.

Remember if that pops up again what to do...or replace the switches.

You can always request me...but when I am not online they tend to get snatched up..but all you need to do is mention to release to Billy.

I fit this in around my "real job" and as in today cleaning guttersSmile.

Let me know if any further issues,

I thank you again for the patience


BillyHvac and other HVAC Specialists are ready to help you

Related HVAC Questions