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IdahoBiker · Jan 8, 2009, 04:06 PM

:( I have a Day & Night Furnace MODEL # 397HAW036060 (1982), the Problem(s) are as Follows:
1) The Blower is coming on BEFORE the Burner starts to Cycle, and runs for about 10-12 minutes on Hi-Speed, blows a lot of cold air into the House...Isn't the Burner supposed to Start 1st?? How to Correct??
2) When the Burner starts Cycling, it ignites burns for about 10 seconds then "Blows-Out", REPEATS this 6-9 Times Before it starts Burning Constant...How do I Correct this??
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NOTES:
1) Electronic Control Board was Replaced with a New/Updated version 3 Years ago
2) Main Control Valve, Flame Sensor & Blower Motor were Replaced 2 Years ago
**Electronic Igniter "clicks" 4-5 times and then the Pilot comes on with a Constant 3/4" long Blue Flame.
**Burner Carryover is Good, and all burners Burning at Same Flame Rate, & Spread (Blue)
**When the Tech Replaced the Fan Motor, the Wiring was Different, but he said that was an Easy Fix, I wonder if he got his Wires Crossed:rolleyes:, Pardon the Pun...
************************************************** ************************
Seems That I'm using a Lot of Unnecessary Gas Usage to Heat My Home, can These Problems Be rectified?? What can "I" do to Correct these or this Problem(s)?? I have invested a Few Bucks in Updating this Furnace, and gotta draw the Line someplace, can't afford a New Furnace at this point. Seems like This is a Fixable Problem(s)??
Walkthrough on Repair/Troubleshooting?? WHERE? could I attain a Schematic of this Unit?? the one on the Cover is really worn.
THANK YOU

KC13 · Jan 8, 2009, 04:48 PM

Has there been a thermostat replacement recently, by chance? A heat pump thermostat, by chance? Under normal conditions, the blower doesn't run until the unit pre-heats, unless the thermostat fan selector switch is set to "on".

letmetellu · Jan 8, 2009, 05:31 PM

This furnace probably has a time controlled fan switch, mean ing that the fan will come on something like 90 seconds after the theromstat calls for heat. Since you spark ignitor is not igniting the pilot on the first few sparks, this is taking some time. Also after the spark ignitor does light the pilot the flame has to hit the pilot, shich is a bi-metal switch, long enough for it to switch off the sparker and then move further to open the second stage of the redundant gas valve, all of this is probably taking the 10 - 20 minutes that you are talking about.

One cause of all of this is that the pilot is not hitting the bi-metal strip in the right blace or the pilot may not be big enouh. Anothet cause could be that the tension of the strip has been shot from all the years of heating.

It has been a while since I bought one of these pilots but I think it is called a "2 H pilot assembly", you will want a three wire assembly. You might check for some prices on the internet and also on Carrier.

KC13 · Jan 8, 2009, 05:33 PM

Part # LH680005 if you need one.

IdahoBiker · Jan 9, 2009, 06:47 PM

OK, Checked that Part out, found an eBay one for $50/New... Since the "electrode-Flame Sensor" is separate, do you think it is OK?

letmetellu · Jan 9, 2009, 07:15 PM

Make sure that the part you found is the right part, look at some pictures or something.

If your flame has never come on while this has been happening there is no way to say that the flame sensor is good, but I would tell you to clean the sensor with a sand cloth while you have things apart. Just polish it up a bit and get all of the junk off that has built up.

IdahoBiker · Jan 12, 2009, 02:28 PM

Originally Posted by letmetellu

Make sure that the part you found is the right part, look at some pictures or something.

If your flame has never come on while this has been happening there is no way to say that the flame sensor is good, but I would tell you to clean the sensor with a sand cloth while you have things apart. Just polish it up a bit and get all of the junk off that has built up.

Yes, The Burners Light(which tells me the Igniter/pilot is working... just maybe NOT right? ), then go out, repeats this process 6-9 times Before the Burners continue to Burn Constant... and of course the Blower is Running during this whole "cycling-process"...
Sure Hope this Pilot assembly Part # LH680005 will cure this Problem?

IdahoBiker · Jan 12, 2009, 02:32 PM

Originally Posted by KC13

Part # LH680005 if you need one.

Would YOU have one of these for Sale? I was Bidding on One at eBay, and Had my Browser Crash 3 minutes before the Close... I'm sure you appreciate the Fact in this Time of Recession, I'm just trying to save a Few $$$

KC13 · Jan 12, 2009, 05:21 PM

Originally Posted by IdahoBiker

Would YOU have one of these for Sale?? I was Bidding on One at eBay, and Had my Browser Crash 3 minutes before the Close...I'm sure you appreciate the Fact in this Time of Recession, I'm just trying to save a Few $$$

Visit americanfurnaceparts.com

IdahoBiker · Jan 13, 2009, 02:44 PM

Originally Posted by KC13

Visit americanfurnaceparts.com

Do You have a Different URL for that site? Keep getting Page can't load error, Googled it too, and found no link?

KC13 · Jan 13, 2009, 03:34 PM

Originally Posted by IdahoBiker

Do You have a Different URL for that site?? Keep getting Page can't load error, Googled it too, and found no link??

Sorry dude, it's actually furnaceparts.com

IdahoBiker · Jan 18, 2009, 02:12 AM

Originally Posted by KC13

Sorry dude, it's actually furnaceparts.com

Well I finally found the Pilot Burner, Igniter, & Flame Sensor} got them ALL Brand New OEM for 41.99 including Shipping:)
Will wait for them to get here, and Install, and see what Happens, sure hope this solves this issue?
A Few Posts ago you referred to a Heat Pump Thermostat, YES, one was Installed several Years ago when We had a Heat Pump, but then that got replaced a couple of Years Later by a AC Compressor (But they opted to Keep that Thermostat)... the Way it was wired, I have to switch to "Emergency Heat" & set the Fan to Auto ( I was informed that it wouldn't be cost effective at this point to do a Re-Wire of this System)... While we are on this Subject, since the New Motor(Intake Fan/Blower) was installed, I have never Heard it run on Low-Speed, it always Runs on High, so WHY? Have a 2-speed Fan anyway?

hvac1000 · Jan 18, 2009, 06:37 AM

Ebay

LH 680 005 Carrier 3 Wire Pilot Burner - eBay (item 320333211310 end time Jan-24-09 07:35:42 PST)

KC13 · Jan 18, 2009, 06:45 AM

Check the wiring between the blower and the circuit board. It may have been wired to use the same speed at all times. This unit typically has a 3 or 4 speed motor, and an increase or decrease in speed by 1 (i.e. medium-low to medium-high) is not always very noticeable. Usually the heating speed (red) is connected to the "LO" terminal and cooling speed (black) to the "HI" terminal at the board. The blower originally had a 4 tap molex connector for convenience of changing speed. I prefer to preserve this feature when replacing the OEM motor with an aftermarket motor, but some techs will eliminate it and wire direct to the board.

IdahoBiker · Jan 18, 2009, 01:36 PM

Originally Posted by hvac1000

Ebay

LH 680 005 Carrier 3 Wire Pilot Burner - eBay (item 320333211310 end time Jan-24-09 07:35:42 PST)

Thanks for the Heads-Up on That eBay item, but I already made a Purchase @ eBay from a different seller Saturday. I Bought a New Carrier OEM Pilot Burner, Igniter, AND Flame Sensor for $40.99 including Shipping... But THANKS for letting me Know, appreciate that!

KC13 · Jan 18, 2009, 01:50 PM

Originally Posted by KC13

Check the wiring between the blower and the circuit board. It may have been wired to use the same speed at all times. This unit typically has a 3 or 4 speed motor, and an increase or decrease in speed by 1 (i.e. medium-low to medium-high) is not always very noticeable. Usually the heating speed (red) is connected to the "LO" terminal and cooling speed (black) to the "HI" terminal at the board. The blower originally had a 4 tap molex connector for convenience of changing speed. I prefer to preserve this feature when replacing the OEM motor with an aftermarket motor, but some techs will eliminate it and wire direct to the board.

Umm, this was supposed to go somewhere else... don't know how it got here...

IdahoBiker · Jan 18, 2009, 03:14 PM

Originally Posted by KC13

Umm, this was supposed to go somewhere else...don't know how it got here...

Perhaps, This is the RIGHT Place... as in My Original Post, I had Stated that I Had Replaced the Blower Motor (after-market) that appears to Run on Hi-Speed always... My Blower is Running BEFORE the Furnace starts the Ignition Cycle...

KC13 · Jan 18, 2009, 03:17 PM

Originally Posted by KC13

Umm, this was supposed to go somewhere else...don't know how it got here...

Umm, this was supposed to go somewhere else... don't know how it got here... how's that for a recovery?

KC13 · Jan 18, 2009, 03:19 PM

Originally Posted by IdahoBiker

Perhaps, This is the RIGHT Place...as in My Original Post, I had Stated that I Had Replaced the Blower Motor (after-market) that appears to Run on Hi-Speed always...My Blower is Running BEFORE the Furnace starts the Ignition Cycle...

Say... is there a wire connected to "GH" on the circuit board?

IdahoBiker · Jan 18, 2009, 03:28 PM

Originally Posted by KC13

Say...is there a wire connected to "GH" on the circuit board?

Don't Know, will have to Go Look... will be In touch