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 Pulse 21 Problems
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windguy

8 Posts

Posted - 12/06/2009 :  5:38:25 PM  Show Profile  Reply with Quote
Some of the other threads have very similar symptoms for different heating systems. I do plan on calling the local Lennox service company tomorrow, but was curious what the online experts think might be the problem. I hate calling in a tech since I'm a consummate DIYer but I have no experience with heating systems.

The system was installed in 1993 by the previous home owner and since 1997 it's never been serviced. I changed the blower motor myself last summer during the AC months. The one thing I did notice that's changed from last season is the outflow from the direct vent seems a lot less. The system used to spit out a good amount of moisture when starting up but it doesn't seem to do that when the system does turn on. Symptom wise, the automatic ignition system green light comes up, I can hear the purge blower running then the ignition system's relays click for about 5 seconds every 25 or so seconds for about 4 attempts then the purge blower shuts off and the green light flashes. The system has been intermittent the past few weeks but for periods would run okay. Now, the heater will rarely turn. If it does turn on, the blower will run for a few minutes then shut off, so the problem has progressively gotten worse to the point that it's not functional. The fan does work okay by itself if set by the thermostat. And yes, it is cold in the house and I'm in the doghouse until the heater gets fixed

Appreciate any advice
Thanks!

slctech

2085 Posts

Posted - 12/06/2009 :  8:40:51 PM  Show Profile  Reply with Quote
Pulses are a unique breed.
Sounds like an ignition issue of sorts. Most pulses will cough a bit before failing to start all together.

Technician should perform a heat exchanger pressure test as outlined by Lennox.
If the heat exchanger passes, then install new air flapper.
Clean and check all drain/condensate components and piping.
Clean secondary heat exchanger if needed
Clean A/C coil if needed
Be aware that the gas valve on the Pulse has very erratic readings on the output, this is normal. The gas valve is one of the only in the industry with a 2.0wc setting..most are around 3.5wc. See to many technicians screwing around with this and leaving a Pulse worse off than when they arrived.

Here is the Lennox's check list..
http://tech.lennoxintl.com/PDFs/9358e.pdf

As a Lennox Technician I feel basic repairs and maintenance can be performed by the homeowner. But I highly suggest that periodic maintenance should be made by a certified licensed technician. You should contact your local Lennox technician for any repairs or issues that are outside your comfort zone. Property damage, personal injury, and death can occur from improperly repaired or maintained systems. Replacing a part doesn't always resolve the issue that caused the part to fail!
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windguy

8 Posts

Posted - 12/06/2009 :  9:30:49 PM  Show Profile  Reply with Quote
Much thanks SLCTech.
Appreciate the quick reply and you taking the time to give me info on what to expect out of this service call. This is exactly what I was looking for.
I'll post an update after the tech is finished and I'm done crying over the bill

Happy Holidays
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slctech

2085 Posts

Posted - 12/06/2009 :  9:36:10 PM  Show Profile  Reply with Quote
Pulses are wonderfully efficient and reliable, in my experience. The only downfall is they require more maintenance than any other furnace out there. And maintaining them is not cheap.

Good Luck and do let us know how it goes.

As a Lennox Technician I feel basic repairs and maintenance can be performed by the homeowner. But I highly suggest that periodic maintenance should be made by a certified licensed technician. You should contact your local Lennox technician for any repairs or issues that are outside your comfort zone. Property damage, personal injury, and death can occur from improperly repaired or maintained systems. Replacing a part doesn't always resolve the issue that caused the part to fail!

Edited by - slctech on 12/06/2009 9:36:43 PM
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windguy

8 Posts

Posted - 12/06/2009 :  11:54:03 PM  Show Profile  Reply with Quote
thanks

just curious, what's the life expectancy of a Pulse system?
was wondering how many years they typically go. thanks
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windguy

8 Posts

Posted - 12/10/2009 :  8:08:20 PM  Show Profile  Reply with Quote
12/10/09 UPDATE

The service tech checked out the furnace today. Of course it was running great when he arrived. Actually, it's been running perfect for the last five days. Interesting.

They wanted $1,000 to perform a tune-up on the system. Yes, $1,000.
Supposedly his manager claims it's hard to get parts for the Pulse systems. After I scraped my jaw off the floor we discussed options on what I can do. He thought changing the ignition control would be a good idea. He also suggested cleaning/changing the air flapper.
I see there are tune-up kits available but how about just a flapper?
I see there is a diagraph kit. Would it be okay to just to get one of those in case changing the ignition control doesn't solve the problem?

Thanks for the help!
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windguy

8 Posts

Posted - 01/10/2010 :  10:56:55 AM  Show Profile  Reply with Quote
01/10/10 UPDATE

The heater started working again, sort of, so I put off changing out the control unit. That didn't last long so I went ahead and installed the new one that I got from CozyParts, who had the best pricing with shipping. Also got an air flapper as insurance, which I didn't need but well worth having.

For those DIYers, changing out the control unit is very straight forward and requires minimal tools. About a one hour job max but could be done in 10 minutes the second time around so don't shy away from taking on this type of repair. The new Johnson Controls replacement kit for pulse units is well designed. Can't say much for the small access panel in the furnace to get to the sensor wire, which needs to be replaced since the termination on the control board side is different, plus I needed more wire length. Suggest using a small mirror so you can see what's going on inside the housing. No step by step instructions with the replacement board so you will need to figure this out yourself. I could list out the step but that would ruin all the fun

Heater is working perfectly now. My only regret was that I didn't replace the part sooner.
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dan.meyer

2 Posts

Posted - 01/12/2010 :  9:32:27 PM  Show Profile  Reply with Quote
quote:
Originally posted by windguy

01/10/10 UPDATE

The heater started working again, sort of, so I put off changing out the control unit. That didn't last long so I went ahead and installed the new one that I got from CozyParts, who had the best pricing with shipping. Also got an air flapper as insurance, which I didn't need but well worth having.

For those DIYers, changing out the control unit is very straight forward and requires minimal tools. About a one hour job max but could be done in 10 minutes the second time around so don't shy away from taking on this type of repair. The new Johnson Controls replacement kit for pulse units is well designed. Can't say much for the small access panel in the furnace to get to the sensor wire, which needs to be replaced since the termination on the control board side is different, plus I needed more wire length. Suggest using a small mirror so you can see what's going on inside the housing. No step by step instructions with the replacement board so you will need to figure this out yourself. I could list out the step but that would ruin all the fun

Heater is working perfectly now. My only regret was that I didn't replace the part sooner.

windguy - Is the part you replaced the ignition control module - Johnson controls part number G891TCA-8103? I am having the same problem with my Pulse 21. I replaced this same module 7 years ago but I don't remember if the symptoms I have now are the same as then but I believe think they are.
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windguy

8 Posts

Posted - 01/13/2010 :  12:21:20 AM  Show Profile  Reply with Quote
quote:
Originally posted by dan.meyer

quote:
Originally posted by windguy

01/10/10 UPDATE


windguy - Is the part you replaced the ignition control module - Johnson controls part number G891TCA-8103? I am having the same problem with my Pulse 21. I replaced this same module 7 years ago but I don't remember if the symptoms I have now are the same as then but I believe think they are.



Hi Dan,

The JC ignition control module is "60J00 Ignition Control Used on ALL Lennox Pulse furnaces, 60J0001 - $210.77" It's a blue painted module. I'm pretty sure this unit is good for all pulse furnaces based on the description and it is the right one for a Pulse 21, but confirm this with the guys at Cozyparts. I was told by the Lennox repair tech that initially stopped by, for a $90 chat, that the JC boxes last about 7 years, not as long as the original control box so you may be due for one. The control box really had a bad case of dementia near the end of its life. Was planning an official autopsy first before burial but may forgo and let it rest in peace with dignity.

Good Luck.

Edited by - windguy on 01/13/2010 12:26:27 AM
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MechAcc

1499 Posts

Posted - 01/13/2010 :  07:40:16 AM  Show Profile  Reply with Quote
Pulses need servicing from time to time. Heat exchangers need to be pressure tested every 4 years. Heat exchanger leaks can cause ignition problems. So rather than spending money on ignition controls that may or may not fix the problem get the heat exchanger pressure tested to eliminate that a possible cause. If the heat exchanger passes the pressure test then have the furnace serviced. Air diaphragm holder cleaned, diaphragm replaced. The gas port opposite of the spark plug opening needs to be cleaned. Have flame sensor cleaned. Vent pipe drip leg condensate piping. Debris collects in the bottom of the drip leg and restricts the flow of condensate. The production of condensate can exceed the removal rate. When the condensate builds up high enough where it restricts the venting of combustion gases and the flame signal strength will decay on cycle the furnace off. If the bottom of the drip leg has a glued on pvc cap your technician will need to remove the cap to clean out the debris. A rubber hub cap with hose clamp can then be installed in place of the glued cap. This will allow the cap to be quickly removed for future cleanings. Erratic gas pressures can be smoothed out by replacing the gas flapper assembly.

Have them clean the blower assembly and the secondary heat exchanger and evaporator coil. These actions will improve air flow.

Have technician perform a combustion test as is required. This will ensure that the furnace is burning correctly. Just because the furnace runs doesn't mean that it is running correctly a combustion test will determine if it is burning correctly.

I am not an employee of CozyParts. The opinions that I post are my own.

Please have your furnace inspected annually by a qualified service technician. Have all of your fossil fuel appliances tested annually for carbon monoxide production by a professional.

Get a good Carbon Monoxide Alarm. Replace it according to manufacturers recommendations usually every 3-5 years. CO concerns are not just for the winter but 24-7. UL approved alarms alarm high. For a low level alarm do a search for CO Experts or NSI 3000 a low level CO monitor.

Edited by - MechAcc on 01/13/2010 07:45:07 AM
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dan.meyer

2 Posts

Posted - 01/23/2010 :  12:46:52 PM  Show Profile  Reply with Quote
Update: I replaced my ignition control module and now the furnace is working normally again.
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MechAcc

1499 Posts

Posted - 01/23/2010 :  1:26:37 PM  Show Profile  Reply with Quote
Excellent. Did you get the other cleanings and checks done?

I am not an employee of CozyParts. The opinions that I post are my own.

Please have your furnace inspected annually by a qualified service technician. Have all of your fossil fuel appliances tested annually for carbon monoxide production by a professional.

Get a good Carbon Monoxide Alarm. Replace it according to manufacturers recommendations usually every 3-5 years. CO concerns are not just for the winter but 24-7. UL approved alarms alarm high. For a low level alarm do a search for CO Experts or NSI 3000 a low level CO monitor.
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dmehmen

1 Posts

Posted - 01/26/2010 :  8:15:07 PM  Show Profile  Reply with Quote
I am having problems with my pulse furnace starting. I think I have figure out what the problem is but wanted to get info from some experts. I went down to check out the furnace since it was not running and I flipped the braker off and turned it back on. The furnace tried to ignite but had a gurgling sound that seemed to be coming from the air intake piping. This pipe goes out of the house to the west and we have had some good rains/ snows this winter with some pretty good winds. Would this mean that the flapper is going or has gone bad? Also there is a plug at the bottom of the intake piping, should I remove the plug and drain the fluid out of it and install the plug again? If any of you have any suggestions or info on this please let me know....The furnace just started again but not sure if it will keep running all night with out one of us checking on it. hank you in advance for the help and info.
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MechAcc

1499 Posts

Posted - 01/26/2010 :  10:12:47 PM  Show Profile  Reply with Quote
The furnace heat exchanger needs to be pressure tested every 4 years for leaks and the air diaphragm needs to be replaced as well. You'll need to contact a Lennox dealer to get the heat exchanger pressure tested.
The following are the recommended service procedures that need to be done to the Pulse furnace.

In order to maintain the efficiency and reliability of the Pulse furnace, the following service guidelines have been established and should be performed on each scheduled service inspection of a unit. As with any gas-fired appliance, incomplete combustion (CO) caused by improper maintenance along with leaks in the system could result in serious personal injury.

Inspect heating system yearly. Inspect intake and exhaust PVC pipe for condensate leaks or joint separation. Repair, as necessary.

Check supply and manifold gas pressure. Adjust pressure, as necessary.

Check furnace firing rate by clocking gas meter. (Refer to installation instructions.)

Test oxygen / carbon dioxide level of flue gas to determine if proper combustion is taking place.

Test carbon monoxide levels in flue gas. Level should never exceed 50 PPM.

Check temperature rise and make sure proper blower speed is selected to match nameplate rating.

Inspect heat exchanger assembly for any signs of corrosion.

Inspect secondary heat exchanger for dirt build-up and clean, as necessary.

Inspect air diaphragm flapper material for dirt or deterioration and replace, if necessary. Air flapper material must be replaced every four years regardless of appearance.

Perform a pressure test of the heat exchanger and combustion chamber every four years.

Inspect gas intake flapper material for dirt or deterioration. Replace entire gas intake assembly if flapper material is found to be worn.

Inspect purge blower for dirt build-up every year and clean, as necessary.

Inspect stainless steel flexible gas connector for corrosion.
Remember -- Some soaps used for leak testing are corrosive to stainless steel. Failure to thoroughly rinse gas connector after leak check can lead to corrosion.

Check supply air blower wheel and clean, as necessary.

Check fan and limit controls for proper operation and setting.

Check all wiring for loose connections. Check for correct voltage.

Inspect intake and exhaust pipe terminations to make sure they are free from obstruction.

Inspect condensate lines for free flow of condensate during operation.

Instruct homeowner to inspect filter monthly and clean or replace, as needed. Dirty filters cause inefficient operation. Running the unit with a dirty filter or without a filter could cause premature
heat exchanger failure.

Verify and check operation of existing CO detector.

The gurgling sound is coming from backed up water. Tell the dealer that you have a water back up problem.

I am not an employee of CozyParts. The opinions that I post are my own.

Please have your furnace inspected annually by a qualified service technician. Have all of your fossil fuel appliances tested annually for carbon monoxide production by a professional.

Get a good Carbon Monoxide Alarm. Replace it according to manufacturers recommendations usually every 3-5 years. CO concerns are not just for the winter but 24-7. UL approved alarms alarm high. For a low level alarm do a search for CO Experts or NSI 3000 a low level CO monitor.
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windguy

8 Posts

Posted - 01/26/2010 :  11:51:42 PM  Show Profile  Reply with Quote
quote:
Originally posted by dmehmen

I am having problems with my pulse furnace starting. I think I have figure out what the problem is but wanted to get info from some experts. I went down to check out the furnace since it was not running and I flipped the braker off and turned it back on. The furnace tried to ignite but had a gurgling sound that seemed to be coming from the air intake piping. This pipe goes out of the house to the west and we have had some good rains/ snows this winter with some pretty good winds. Would this mean that the flapper is going or has gone bad? Also there is a plug at the bottom of the intake piping, should I remove the plug and drain the fluid out of it and install the plug again? If any of you have any suggestions or info on this please let me know....The furnace just started again but not sure if it will keep running all night with out one of us checking on it. hank you in advance for the help and info.



dmehmen,

Sorry to hear you're having heater problems.
I am not a repair person and have very limited experience with heaters. The experts have weighed in with their advice. I'll give you my take. Don't know your situation in getting a repair person out to see your unit, but in my situation it was cost prohibitive.

MechAcc gave some good advice a few posts ago regarding the vent pipe. I actually want to drain mine but it has a glued on cap now. I bought at Home Debit a 1.5" PVC adapter that has male threads on one end so I plan to cut the cap off and glue that on and use a threaded cap for future cleanings. I like this solution better than using hose clamps on a rubber hub cap but I like the idea he suggested in terms of maintaining this part of the system and appreciate his advice. As far as the other tests that need to be performed, everyone's situation is different in what can be accomplished. When the heater turns on, there is a purge motor that runs for a set amount of time, it might be 30 seconds. Then the fan motor should turn on. I had problems with my controller board and the turning on process was very erratic. Recycling power sometimes helped, but it was a short lived solution. By recycling power, you are resetting the controller board so it starts the sequence all over. A new controller board cured the problem for me. It's my understanding that controller boards last around seven years or so. The original one in ours lasted 16 years. Hope this info helps. Again, I'm not a repair person but only a DIYer. Good luck and hope you stay warm


Edited by - windguy on 01/27/2010 12:06:38 AM
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teacher10258

1 Posts

Posted - 02/02/2010 :  9:32:43 PM  Show Profile  Reply with Quote
I bought the 60J0001 Control Unit and the sheet in the package said neutral wire is not needed on this unit, tape it off etc. I have been trying to find the information that says which wire is the neutral and have had no luck. Anybody that has done this replacement and figured it out? Is it on of the 6 wires in the connector or somewhere else in the unit?
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