Lennox Gas Furnaces Specifications
Lennox G8 Furnace Manual
Lennox G8 Furnace
Lennox Furnaces Gas
Lennox G8 Furnace Manual Diagram

Lennox® Furnace Service Manuals The Adobe Acrobat Reader® Application is Needed to Read '.pdf' Files Click Here to Get a Free Copy of Acrobat Reader® Click on Your Model Number Below to View the Service Manual for Your Unit. Click Here to Watch a Video on How to Locate your Model Number. O23/OHR23/OF23: 80MGF Series: 80UHG Series: 90UGF.

Looking for more information about your Lennox product? Find your owner’s literature, like product manuals, by searching your product’s model number.
MLA, MPA, MPB and 3PB Single and Multi-Zone Outdoor Units wih Compatible Indoor Units Service Manual Packaged Elec/Elec / Heat Pump LRP14AC, LRP14DF, LRP14GE, LRP14HP, LRP16GE and LRP16HP Residential Packaged Units.
MLA, MPA, MPB and 3PB Single and Multi-Zone Outdoor Units wih Compatible Indoor Units Service Manual Packaged Elec/Elec / Heat Pump LRP14AC, LRP14DF, LRP14GE, LRP14HP, LRP16GE and LRP16HP Residential Packaged Units.

Heat exchanger can crack for various reasons and should be checked every time furnace is repaired or maintained.

Visually check heat exchanger for cracks

You will find most cracks form near the back and where the heat exchanger metal bends, Since this is where it will be weakest due manufacturer weakening the metal by bending it.
Watch the flames as the furnace fan starts if you see the flames are blowing around or out the front of the burners then you will need to take a closer look at the heat exchanger

Water test

This test worked best on the old Lennox G8 and would find cracks or pinholes on the heat exchanger that sometime could not be seen.
If there is no air conditioning then it will be easy to access above the heat exchanger through the humidifier. Once the heat exchanger cools down spray water on the heat exchanger from the top insuring full coverage and being careful of the electronics and motors. Then watch inside the burners for water to seep through, A good heat exchanger will not let moisture into burner chamber

Using carbon monoxide detector

Test for carbon monoxide at return air as well at supply air and compare the two readings or test at supply air with burners on then off making sure furnace is not back drafting and compare.
If you take reading once and only at supply air you will not be 100 percent sure the problem is with the heat exchanger. You are testing the accumulation of carbon monoxide over a long period of time from other sources like the furnace or hot water tank back drafting also it could be from outside sources like a vehicles near the intake air.

Reasons for cracks

Lennox Gas Furnaces Specifications

If the furnace does not have enough combustion air it will cause the furnace to run hotter then designed. Then with more expansion and contraction in the heat exchanger it causes cracks. The gas pressure must be set as per furnace name plate derated for location altitude if too much gas heat exchanger will run too hot.Blower speeds must be checked by comparing furnace temperature difference to name plate rating if running too hot increase fan speed and recheck temperature supply air minus return air.

Any crack in a heat exchanger is dangerous and the heat exchanger must be replaced when crack is found

Thank you for visiting my blog I would appreciate any feedback I can get, Please leave a comment on whether my information has helped you. I am always interested in more topic to write so feel free to leave a comment asking about anything related to HVAC-R (Heating, Ventilation, air conditioning, refrigeration).

Thanks for reading my blog

Tagged: carbon monoxide, cracked heat exchanger, heat exchanger

POST a QUESTION or COMMENT about where to find furnace or boiler installation and service or maintenance manuals and guides

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Lennox Manuals, parts lists, wiring diagrams for HVAC equipment:

Free downloadable manuals for Air Conditioners, Boilers, Furnaces, Heat Pumps. Here we provide free downloadable copies of installation and service manuals for heating, heat pump, and air conditioning equipment, or contact information for the manufacturers who can provide that information for nearly all major brands of HVAC equipment.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Lennox Furnaces, Heat Pumps, Air Conditioners - Contact Information, Manuals, Data Tag Decoding - contact information

Free Lennox Furnace, Heat Pump, Air Conditioner Installation & Service Manuals, Wiring Diagrams, Parts Lists

Below we provide HVAC manufacturer contact information and direct links to free downloadable installation, service, and users manuals, focusing on hard-to-find manuals for older models or discontinued equipment. We also provide links to the manufacturer's current model lists and literature.

See LENNOX HVAC MANUALS & PARTS GUIDES Industries Air Conditioners, Furnaces, Heat Pumps , Manuals, Guides

To find a Lennox Dealer near you go to http://www.lennox.com/residential/ and enter your zip code in the box at the web page upper right corner,ORuse the links to Lennox at the left side of this web page (supplied by Google).

Contact information for Lennox industries, in Dallas Texas:
Lennox Corporation - 1-800-9-LENNOX (1-800-953-6669)
2100 Lake Park Blvd.
Richardson, TX 75080
P.O. Box 799900
Dallas, TX 75379-9900
NAIC: 333415 Air Conditioning & Warm Air Heating Equipment & Commercial & Industrial Refrigeration Equipment Manufacturing; 333414 Heating Equipment Manufacturing, Except Warm Air Furnaces; 333994 Industrial Process Furnace & Oven Manufacturing; 336322 Other Motor Vehicle Electrical & Electronic Equipment Manufacturing; 42173 Warm Air Heating & Air Conditioning Equipment & Supplies Wholesalers

Also see Lennox data tag decoding information under the letter L

at DATA TAGS on AIR CONDITIONERS

LINKS to OLDER, hard-to-find Lennox HVAC equipment manuals are provided at this website - LENNOX MANUALS & GUIDES - HVAC just below.

The Lennox Pulse furnace safety inspection is (or was) free, but if the furnace has to be cleaned in order to be inspected, the customer could be charged for the cleaning.

See Lennox PULSE FURNACE SAFETY WARNING .

At Technical Reviewers & References we provide more contact information, links to current model list information, product specifications, and installation/operation manuals

Lennox: free, downloadable Lennox Pulse Furnace User's Manuals and Service Manuals are listed just below:

Safety: owners of older model Lennox Pulse Furnace heating equipment should also see Lennox PULSE FURNACE SAFETY WARNING - Lennox Pulse Furnace Safety Inspection/Warranty Program: Carbon Monoxide Warning
That document describes carbon monoxide gas (CO) leak safety hazards on certain models of Lennox hot air heating furnaces and announces an inspection and recall/repair program for these systems.
Lennox PULSE FURNACE SAFETY FAQs - web page
Lennox PULSE FURNACE SAFETY WARNING - web page
See also HEAT EXCHANGER LEAKS for more information about heat exchanger leaks and furnace safety
and
See also CARBON MONOXIDE GAS TOXICITYfor information about carbon monoxide.

Also see ARMSTRONG Air: Armstrong oil furnaces, Armstrong gas furnaces, Armsrtong heat pumps, packaged units & air handlers or coils
Lennox AIR COOLED CHILLERS IO MANUAL [PDF] retrieved 2019/01/07 original source http://webmanuals.lennoxeurope.com/Current%20Products/Chillers/Water_cooled_chillers/MCW/Installation%20and%20op.%20manual%20%20(IOM)/CHILLER_AC-IOM-0105-E.pdf<

Lennox G8 Furnace Manual