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Doomed Lennox Pulse in Awkward Location?

niftyc Member Posts: 17
We bought a new house in Michigan and found ourselves the proud owner of a 1988 Lennox Pulse furnace.

Pics of the label:

<a href="http://www.flickr.com/photos/niftyc/7717314158/in/set-72157630913585462/">http://www.flickr.com/photos/niftyc/7717314158/in/set-72157630913585462/</a>

<a href="http://www.flickr.com/photos/niftyc/7717318022/in/set-72157630913585462">http://www.flickr.com/photos/niftyc/7717318022/in/set-72157630913585462</a>

Before we bought the house, the home inspector tested the furnace and found it worked (including a CO test). He warned us the unit was old but he thought we could get a few more years out of it. After we bought the house, we had an HVAC guy come to service the unit and he educated me about how "special" the Pulse is. He wouldn't touch it.

I found another HVAC guy -- a Lennox dealer who works with the Pulses -- and he came out and did a pressure test. He found that the heat exchanger has failed and he says the only solution is to replace the furnace. He suggests a Bryant 987M.

After reading all about the Pulse on this board, that's sounds OK. However, the home inspector and now two HVAC guys have also had some comments about the installation location and I'm wondering if I should address that as well. The two pros do not agree about how important this is, and so I'm not sure what to think. Here's the rundown:

The unit is located in an uninsulated attic space above bedrooms.

Access is via a very narrow and difficult stairway: (c. 1890) <a href="http://www.flickr.com/photos/niftyc/7717318662/in/set-72157630913585462/">http://www.flickr.com/photos/niftyc/7717318662/in/set-72157630913585462/</a>

There is extensive water damage below the unit:

<a href="http://www.flickr.com/photos/niftyc/7717317332/in/set-72157630913585462">http://www.flickr.com/photos/niftyc/7717317332/in/set-72157630913585462</a>

<a href="http://www.flickr.com/photos/niftyc/7639630436/in/set-72157630734825436">http://www.flickr.com/photos/niftyc/7639630436/in/set-72157630734825436</a>

A previous owner constructed a drywall room in this attic space and put the Lennox in it with a fire suppression sprinkler system.

As I understand it from the information from the HVAC pros:

- the attic is not insulated and it is not ideal to locate a furnace in an uninsulated area

- the fire suppression sprinkler line is directly below the uninsulated roof, and it could freeze and burst.

- there should be a drain pan in case of leaks. it should have a separate drain (not the condensate drain) and a float cutoff switch to shut off the unit if water is detected in the pan

We could simply replace the furnace and not worry about these three points. We could try to retrofit a drainpan (I'm told this is a really big job -- a problem is that there is no logical drain except the condensate drain which is very small). We could insulate the room. We could move the furnace somewhere else in the house (obviously a big job).

Any comments on this situation? I like to research this stuff, so if there are threads that I haven't found that would help me I'd be delighted to read up.

I really appreciate the generous people on these boards who like discussing HVAC with homeowners like me. Thank you so much in advance for any pointers.


Also I saw on the boards that Pulse owners used to get a discount on a new furnace if they went with Lennox since Lennox abandoned the design and there are no replacement parts. However my most recent info on that is a 2007 PDF (<a href="http://www.globalqualityhvac.com/articles/wgya/50958_wgya_pulse_furnace.pdf">http://www.globalqualityhvac.com/articles/wgya/50958_wgya_pulse_furnace.pdf</a>) on a third-party site and I can't find any info on the Lennox Web site. The HVAC guy knew all about the earlier recall of the Pulse but he didn't know about any warranty discount program that would still be active. Does anyone know about that?


  • VictoriaEnergy
    VictoriaEnergy Member Posts: 126

    You can hunt down an original warranty card to be sure, but typically longer warranties apply to the original purchaser only, so you'd possibly be out of luck if it was only 7 years old, at 24 it has had a reasonably good service life.  The pulse was one of the very early models of condensing furnace.

    The 987M is an excellent furnace.  Ask your installer to do a heat loss calc and confirm the capacity of the furnace he installs is the smallest possible.  If you install one, please post and tell us about how it works for you.  Its li'l brother the 986T is also a good unit too.
    Home Owners Please Note:

    You are receiving advice from some very skilled pros completely free of charge. One of the reasons I participate is to sharpen my own troubleshooting skills. So; did we get it right? I would be grateful if you extend this courtesy back by posting the final outcome of the issue you are inquiring about. Thanks
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