My 15 yr old Lennox
#1
11-16-22, 03:49 PM
My 15 yr old Lennox
My 15 yr old Lennox fires up when plugged in but doesn't blow heat (and I pull the plug to prevent overheating).
It's a G60UHV(x) series.
I've had "Tecs" loook at it and said I needed a new control board but they were cosly so I went out on Ebay
and bought one (100870-01) and hooked it up last winter but when I wanted heat I'd have to plug it in- the Thermostat seemed to be ignored but did say Wait and Heat On but the furnace would try to start even when the thermo was set to off.
When going back to the original control board that worked for the air conditioning but not heating this spring the AC didn'r work - so I suffered when Sacramento was 116 degrees on Sept 6 2022 .
This winter (now with original CB) the heat would come on for 2 seconds and then shut off - and repeat every 5 minutes.
It pays to take notes when analyzing what the furnace is doing since being 87 tomorrow - I may forget something helpfiul ;-)
I had a controll board that I bought for $25 that I installed today and got past the 2 secaond firing and seemed to be ready to start but heard Expansion noises indicated to me the main blower wasn't working and the heat exchanger was probably taking a beating. so I unplugged.
Think I'm being too comservative - the last "Tec" quoted a prce of $1000 for a control board.
Lennox being proprietary sucks..
It's a G60UHV(x) series.
I've had "Tecs" loook at it and said I needed a new control board but they were cosly so I went out on Ebay
and bought one (100870-01) and hooked it up last winter but when I wanted heat I'd have to plug it in- the Thermostat seemed to be ignored but did say Wait and Heat On but the furnace would try to start even when the thermo was set to off.
When going back to the original control board that worked for the air conditioning but not heating this spring the AC didn'r work - so I suffered when Sacramento was 116 degrees on Sept 6 2022 .
This winter (now with original CB) the heat would come on for 2 seconds and then shut off - and repeat every 5 minutes.
It pays to take notes when analyzing what the furnace is doing since being 87 tomorrow - I may forget something helpfiul ;-)
I had a controll board that I bought for $25 that I installed today and got past the 2 secaond firing and seemed to be ready to start but heard Expansion noises indicated to me the main blower wasn't working and the heat exchanger was probably taking a beating. so I unplugged.
Think I'm being too comservative - the last "Tec" quoted a prce of $1000 for a control board.
Lennox being proprietary sucks..
Last edited by sactostan99; 11-16-22 at 05:15 PM.
#2
11-17-22, 01:29 PM
Group Moderator
Welcome to the forums.
You have an expensive high efficiency furnace there.
That is not a DIY'er friendly furnace.
It's two stage with a multispeed electronic blower.
I doubt the board had a problem. More likely the ECM blower motor failed.
Now you may also have a board mis-wiring problem.
G60UHV(X) installation manual.
I'll help you as much as I can.
You have an expensive high efficiency furnace there.
That is not a DIY'er friendly furnace.
It's two stage with a multispeed electronic blower.
I doubt the board had a problem. More likely the ECM blower motor failed.
Now you may also have a board mis-wiring problem.
G60UHV(X) installation manual.
I'll help you as much as I can.
#3
11-20-22, 02:47 PM
Thanks Pete - I have the manual for G60 - and looking at the blower with flashlight I don't see a capacitor like what shows in the manual.
Not looking forward to pulling the blower housing (cutting zip ties etc) but looks like I have no choice.
Been comparing the wiring to thermo - is the C means cyan and the R red?
Not looking forward to pulling the blower housing (cutting zip ties etc) but looks like I have no choice.
Been comparing the wiring to thermo - is the C means cyan and the R red?
#4
11-20-22, 03:40 PM
Group Moderator
If it's an electronic motor..... there won't be a capacitor.
There will be a lot of wires to the blower motor.
There will be a lot of wires to the blower motor.
#5
11-20-22, 06:13 PM
By bunch of wires you mean for the various speeds the motor provides.
How about the c for cyan and r for red?
How about the c for cyan and r for red?
#6
11-21-22, 10:20 PM
Member
You need to see if the blower motor is getting 120v and speed signals.
Need to use a multi-meter and use service manual (install manual is different) to know what to check. involves probing the molex connector pins.,
If the motor is getting 120v and right signal but not turning on, it could just be the motor control module and not the whole motor/module combo.
Need to use a multi-meter and use service manual (install manual is different) to know what to check. involves probing the molex connector pins.,
If the motor is getting 120v and right signal but not turning on, it could just be the motor control module and not the whole motor/module combo.
#7
11-22-22, 03:13 PM
"You need to see if the blower motor is getting 120v and speed signals."
I found a service manual? - I have a multi-tester
Don't see what would be the motor control module.
I haven't attempted to pull out the blower housing yet.
I found a service manual? - I have a multi-tester
Don't see what would be the motor control module.
I haven't attempted to pull out the blower housing yet.
Last edited by sactostan99; 11-22-22 at 03:35 PM.
#8
12-03-22, 01:04 AM
I understand now how the motor is set up with the controller attached to it.
Finally decided to have an Hvac outfit replace the motor.
Talk about costly - Amyway the furnace works ok for heating only (plug and unplug). There's a jumper from 1 to seven that IGNORES what is set on the thermostat.
It's great having heat again.
Finally decided to have an Hvac outfit replace the motor.
Talk about costly - Amyway the furnace works ok for heating only (plug and unplug). There's a jumper from 1 to seven that IGNORES what is set on the thermostat.
It's great having heat again.
