Installed 53L90 in Lennos G23 but won't start
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Installed 53L90 in Lennox G23 but won't start
I have a G23Q3/4-100-4 furnace (1997) and have been having problems since last winter. Last month I called a repairman because of the intermittent problem of the burners not lighting and was told the flame sensor was cracked. He replaced it and everything was fine for a few days. He came back and readjusted the sensor and said if this didn't resolve the problem it probably was the ignitor (he said this was a common problem with these furnaces) and he wanted $500 to install a new one. Since I couldn't afford that I bought a 53L90 kit and installed today. Now I'm freezing since the furnace doesn't come on and when I switch to fan on, even the fan doesn't come on. The Johnson Control was a G776 model and I made sure to label the wires and even took several pictures before removing anything. I hear a hum, but nothing works. Do any of you guys have an ideas what I can do? I've took pictures of the wiring in the Johnson box and can email to anyone interested. I wired the new box:
1 - Red MV (had to splice on new spade connector)
2 - Yellow (ground) - to me this looks like it's going to the gas burner area (not sure if the correct wire but the only one left) - Didn't have a PV/MV???
3 - Orange PV (had to splice on new spade connector)
4 - Green - new wire screwed to the metal mounting bracket
5 - Yellow (ground) - tracing this wire it goes to the bottom of the furnace
6 - Brown - goes to the combusion air switch
7 - nothing (empty spot)
8 - white - goes to the flame sensor
9 - Redish - goes to the spark electrode - I had to cut off the old, strip it a little and used a quick connect to attach
If needed I can send a picture of this wiring.
Help, I'm really starting to get cold.
1 - Red MV (had to splice on new spade connector)
2 - Yellow (ground) - to me this looks like it's going to the gas burner area (not sure if the correct wire but the only one left) - Didn't have a PV/MV???
3 - Orange PV (had to splice on new spade connector)
4 - Green - new wire screwed to the metal mounting bracket
5 - Yellow (ground) - tracing this wire it goes to the bottom of the furnace
6 - Brown - goes to the combusion air switch
7 - nothing (empty spot)
8 - white - goes to the flame sensor
9 - Redish - goes to the spark electrode - I had to cut off the old, strip it a little and used a quick connect to attach
If needed I can send a picture of this wiring.
Help, I'm really starting to get cold.

Last edited by terrisinstl; 01-07-06 at 08:03 PM. Reason: misspelled words
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How do I send pictures?
Can't seem to find how to add attachments. Send me an email and I'll reply with the pictures. Thanks.
I've put the pictures here: http://photos.yahoo.com/terrisinstl
I wasn't sure which wire to put in the second slot (the PV/MV) since the Johnson one didn't have that. I used one of the yellow ground wires (the one I thought went to the gas valve). I really can't figure out what I did wrong. I thought I followed the directions, checked to make sure everything was snapped in tight and rechecked when it wouldn't turn on, but now even the blower won't turn on when I change it from auto to on.
Thanks for any help, it's getting colder and colder and my 1 little space heater's not doing much.
I've put the pictures here: http://photos.yahoo.com/terrisinstl
I wasn't sure which wire to put in the second slot (the PV/MV) since the Johnson one didn't have that. I used one of the yellow ground wires (the one I thought went to the gas valve). I really can't figure out what I did wrong. I thought I followed the directions, checked to make sure everything was snapped in tight and rechecked when it wouldn't turn on, but now even the blower won't turn on when I change it from auto to on.
Thanks for any help, it's getting colder and colder and my 1 little space heater's not doing much.
Last edited by terrisinstl; 01-07-06 at 08:36 PM.
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you need to check your power to the unit.
You said the fan wont come in even in fan only mode.
looks like that module is installed correctly. did you see if you have 24 volts between TH and GRD do you have 120V to the transformer and 24 out
maybe you disconnect the main power?
So the thermostat gives 24volts between brown TH yellow GRD
unit detects power and does 30 sec prepurge completes a circuit between yellow GRD and orange PV and Ignitor orange then sends 1200 volts DC to the pilot ignitor and ignites the pv gas. then sense white completes a circuit that opens main valve red and turns off spark flame sense continues to sense.
You said the fan wont come in even in fan only mode.
looks like that module is installed correctly. did you see if you have 24 volts between TH and GRD do you have 120V to the transformer and 24 out
maybe you disconnect the main power?
So the thermostat gives 24volts between brown TH yellow GRD
unit detects power and does 30 sec prepurge completes a circuit between yellow GRD and orange PV and Ignitor orange then sends 1200 volts DC to the pilot ignitor and ignites the pv gas. then sense white completes a circuit that opens main valve red and turns off spark flame sense continues to sense.
#5
With the Honeywell you installed there is a wiring change if I remember correctly..It states so in the packaging instructions.. Also you will notice there is a 30 second delay before spark starts
oops master already mentioned 30 sec
oops master already mentioned 30 sec
#6
Check the blower door safety switch. Sometimes they are flimsy enough that if you push on it the wrong way the mounting tab will give a little and not trip the switch when the door is replaced. Like the others already said. Check for 120vac at the main connection and check for 24vac at the thermostat terminals. Let us know how you did. I think the $500 estimate was a little salty and I would have done the same thing you did and tackle myself.
Ken
Ken