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BillyHvac
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22115
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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I have a ruud achiever 90 plus. Blower works on manual but

Customer Question

I have a ruud achiever 90 plus. Blower works on manual but will not fire up or stay on when I click over to the heat button on thermostat. Both green lights are on 1) power 2) ok.
The unit worked last season. The only thing that changed was had my LP line broke last fall by construction workers. That is fixed an have LP running in lines again.
Submitted: 1 year ago.
Category: HVAC
Expert:  BillyHvac replied 1 year ago.
Hello,
What is the exact fault you have? Is the unit not lighting or lighting and going out?....or is the heat blower not running?
Use reply
Customer: replied 1 year ago.
There is nothing. Originally the ok light was blinking twice and then pausing for 2seconds. Now When I push on the safety door switch the green ok light and the yellow light blink off then stay lit for 5 seconds. Still nothing at all happening. No clicking or any sound at all
Customer: replied 1 year ago.
Now I hear a click from a switch on the board that happens at the same time the lights click on and off (the green and yellow lights mentioned above)
Customer: replied 1 year ago.
Tapped on the switch and tried it again and the main fan kicked on and stayed on but no gas or flame came on
Expert:  BillyHvac replied 1 year ago.
do you see a glow from an ignitor?
Customer: replied 1 year ago.
No glow at all.
Expert:  BillyHvac replied 1 year ago.
Ok so for cooling the blower works as it should.
For heat, we do not get any flame....exhaust fan starts and runs...pressure switch is new, but unit never lights?
Customer: replied 1 year ago.
Yes
Expert:  BillyHvac replied 1 year ago.
On heat start up...can you tell if the pressure switch is closing?
Customer: replied 1 year ago.
I cannot tell if it is closing or not
Expert:  BillyHvac replied 1 year ago.
is it a 2 wire switch?
Customer: replied 1 year ago.
Yes
Expert:  BillyHvac replied 1 year ago.
do this exactly
furnace off
remove 2 wires on pressure switch
furn on
AFTER THE DRAFT MOTOR STARTS...touch and hold the 2 wires together.
tell me if starts
Customer: replied 1 year ago.
No gas, fire or ignition. Main fan still keeps running
Expert:  BillyHvac replied 1 year ago.
did exhaust fan start?
Customer: replied 1 year ago.
No
Expert:  BillyHvac replied 1 year ago.
we off on a safety then.
Do you have voltmeter?..we want to check the thermostat wire terminals in furnace R to C
Customer: replied 1 year ago.
Yes I do. Will check
Customer: replied 1 year ago.
When set on ohms the meter show that there is a strong current
Expert:  BillyHvac replied 1 year ago.
we want volts ac~
Customer: replied 1 year ago.
Trying to read the right multimeter line correctly.....it either gets 6.5v or 19v
Expert:  BillyHvac replied 1 year ago.
what is meter selector on?...is that a Simpson 560?