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1950s Olsen Airco Furnace, described by the companys product catalog as an Olsen / Airco Luxaire HVAC Manuals, Parts Lists, Wiring Diagrams

Airco / Olsen HVAC Manuals, parts lists, wiring diagrams for HVAC equipment.

Page top photo: a 1950's Olsen Airco Luxaire heating furnace.

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.

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- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

Olsen Airco HVAC Systems parts, manuals, contact information

Olsen Duomatic wood furnace cited & discussed at InspectApedia.com

Illustration: an Olsen Duomatic CWO / CWO-B Wood Heater - able to burn coal, gas, oil, or wood fuel. BTU output depending on model and fuel, ranged from 90K BTUh to 151K BTUh. Our research (January 2026) did not find parts for these heaters.

Free Olsen Airco Luxaire 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.

Olsen / Airco Heating & Cooling Products include central air conditioning systems, condensing gas fired boilers, conventional gas fired heating boilers, oil fired heating boilers, electric furnaces, oil fired furnaces, and indirect fired water heaters.

The company provides an extensive literature download library for which we give a link just below.

Olsen was re-branded as Luxaire in 1965 and marketed under that brand and also Moncrief. The company was bought by Westinghouse in 1981, sold-on to York.

DMO Industries was a manufacturer of Olsen furnaces and Airco furnaces. Those brands are currently owned by ECR International whose address we give below.

Olsen / Airco is a brand owned by ECR International in Utica, NY. Olsen's headquarters is in Wallacburg, Ontario, Canada, as you'll see in the second contact address given below.

In 1965 Olsen HVAC was re-named Luxaire, Inc. and sold equipment under the brand names Luxaire & Moncrief. Luxaire was cquired by Westinghouse, subsequently re-sold to Borg Warner's York Division in 1981.

Olsen/Airco brand heating furnaces were produced by Duomatic-Olsen, DMO Industries. In 1989 DMO Industries was renamed Olsen Technology, Inc. OIsen Technology was purchased by Canadian Manoir Industries Ltd. and the new company, ECR International Ltd., kept Olsen as a division.

Airco, Olsen & ECR Gas Furnace Manuals

Airco / Olsen Oil Furnace Manuals

1950s Olsen Airco Oil Furnace, described by the companys product catalog as an Olsen's oil furnaces include

Olsen Airco Coal, Wood, Oil, Gas Electric Multi-Fuel Heater Manuals

OlderOlsen Airco Heater Manuals - Archived & Discontinued Products

ECR International Miscellaneous Bulletins

...


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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

Inducer relay used on Olsen Airco Ultramax LP Furnace: White Rodgers WR134-20102-101 wiring

We have an Olsen Ultramax LP fired furnace, Model HDS 90M, Serial #056524-HDLPU. The inducer blower has started to run constantly. I can make it stop by wiggling a contact post on the Inducer Motor Relay, which I want to replace. My relay part #134 20102 101, made by White Rogers, has four contacts..Replacements seem to have six contacts.

Are the four contact relays still available or do I simply use the four needed contacts on the replacement. How do I make sure I'm using the correct posts if the six contact part is my only choice?

BTW- furnace was installed in 1990, been inspected and lubed every year and still runs great!! Thanks for any info. On 2021-01-19 by Steven Manning

Reply by (mod) -

Fair question, Steve; I'd want to look at the White Rodgers wiring diagram for the relay ...

White Rodgers inducer relay WR134-20102-101 at InspectApedia.com

I add that this part is widely available in both OEM form and in third-party manufacturer substitutes.

Here is the wiring diagram found on the White Rodgers inducer relay WR134-20102-101

White Rodgers inducer relay WR134-20102-101 Wiring diagram

 

How to install the air filter on an Olsen Oil Furnace

Air filter in an Olsen Duomatic Oil Furnace (C) Inspectapedia.com PeterWe have a duo matic/Olsen oil furnace and the serial number is 24419 bcilu and model number BCL 115h

and would like to know proper installation of air filter need to know if this is right. On 2020-12-26 by Peter

[Photo above]

by (mod) - check that Olsen furnace air filter is installed on the support brackets in the air handler

Peter

The air filter size in your photo [ 20 x 25 x 1 inches] is correct but

Watch out: it's installation MIGHT be improper if the air filter is not supported on its brackets, and if so, potentially unsafe if the filter collapses and is drawn into moving parts such as the blower (motor overheats, fire risk).

In any air handler an air filter like the one you show is supposed to be resting on supporting angled-steel brackets in the plenum. I can't see those in your photos.

Take a look at the manual drawings for your furnace [or my example below] where they show the air filter location and position.

The manual for your furnace is given as a free PDF download on the page above

OLSEN AIRCO ECR Int'l OIL FURNACE BCL BCL-S BFL IO MANUAL

This manual shows the air filter location on the BCL 120S - 145S - perhaps similar to your Olsen BCL 115 (smaller model); I've marked the air filter and its location in blue. Olsen describes a "permanent" air filter that is to be cleaned.

Your photo shows a replaceable air filter that would be changed monthly or when visibly dirty.

Olsen Airco BCL series furnace parts cited & discussed at InspectApedia.com

- adapted from the Olsen Airco manual cited above.

Excerpt:

A: Routine Maintenance By Home Owner

Other than remembering to arrange for the annual professional servicing of the furnace by the service or installation contractor, the most important routine service performed by the homeowner is to maintain the air filter or filters.

A dirty filter can cause the furnace to over-heat, fail to maintain indoor temperature during cold weather, increase fuel consumption and cause component failure.

The furnace filter(s) should be inspected, cleaned or replaced monthly. The furnace is factory equipped with a semi-permanent type filter. If the filter is damaged, replace with filters of the same size and type. (See Appendix A, Table A-11).

During the routine service, inspect the general condition of the furnace watching for signs of oil leaks in the vicinity of the oil burner, soot forming on any external part of the furnace, soot forming around the joints in the vent pipe, etc. If any of these conditions are present, please advice your service or installation contractor.

Age of an Olsen Furnace Serial 34470HTRL

Can you tell me how old my olsen furnace is. serial 34470HTRL (Jan 23, 2014) Anonymous

Reply:

Referring to Carson Dunlop Associates Technical Reference Guide for Olsen Furnaces (www.olsenhvac.com) the key is the "HTRL" in the serial number.

I'm guessing it's a 1996 furnace based on the following explanation:

In one type of Olsen the year is in the 3rd letter - but the "R" in your serial does not translate - or if it does this unit was built after year "N" which was 1992/3. If we keep counting and guess Olsen kept the same encoding "O"= 1993/4 "P" = 1994/5 "Q"= 1995/6 and "R" would date from 1996/7 model year.

Reader comment:

Thank you so much. There was another number FBL 17327E but the first number I listed was clearly marked as the serial number. Not sure if the FBL17327E was the model, or if it helps in any way. Thanks again for your help.

 

Olson HDS Gas Furnace Ignition Trouble - need manual

I have a 1980's olson gas fired furnace model # HDS 90M Inducer motor runs but wont fire. Spark igniter flashes red light. now on the igniter box it says if flashing refer to manual. I don't have one! been trying to fine one online for the last hour can't find one.

I just want to know what troubleshooting things I need to check. don't think it's the spark igniter says on the unit only replace if red light stays on. any information would be helpful (Dec 10, 2017) terry

Reply:

See our Olsen gas furnace manuals on the page above. If I can find more I'll add them or their links here.

About checking the igniter on your Olsen gas furnace, see the diagnosis and repair procedure

at GAS IGNITER DIAGNOSIS & REPAIR 

Manual for a c. A. Olsen mfg co. Elyria O. Forced air gas furnace

I am looking for a manual for a c. A. Olsen mfg co. Elyria O. Forced air gas furnace model A-1258 series 5 ,100000 btu furnace . Help ! On 2023-01-24 by Mike

by InspectApedia Publisher

@Mike,

A quick search of InspectApedia using the on-page search box to find

"Olsen HVAC" finds this page - the page you're on.

OLSEN AIRCO HVAC MANUALS & PARTS GUIDES

Here we provide free PDF downloads.

 

Duomatic-Olsen Ultramax gas furnace blower seems to not have a working fan limit switch

I have an older Duomatic-Olsen Ultramax gas furnace (1990) that has always worked well. Lately, the main furnace blower starts and stops at the exact same time the thermostat (Honeywell programmable) calls for and cancels heat.

The blower limit switch, a Honeywell L4064B, was replaced about 3 years ago. The inducer blower works as it should. It almost seems like the limit switch no longer controls the furnace blower, but the thermostat instead. Help ! On 2019-11-04 by JW

Reply by (mod) -

JW I'm no smarter than you on this but it does sound as if the limit switch isn't working;

Watch the limit switch dial on the furnace.

On a call for heat, as the plenum heats up the dial should begin to rotate; the blower ought not come on until the dial rotates to show FAN ON under the pointer.

Also typically the fan will continue to run for a bit after the end of a call for heat, to extract and use the remaining latent heat in the furnace though the burner is off, and to cool down the heat exchanger, reducing thermal stress and cracking risk there.

You might also check thermostat wires and thermostat setting - first to be sure there are no shorted wires and second to be sure that the settings on the TT are correct (such as fan AUTO & HEAT modes)

Show us a photo of your thermostat and of your Duomatic (one photo per comment)

Honeywell L4064B pull out tab for low voltage wiring (C) Daniel Friedman at InspectApedia.comby JW - How do I determine if I need the jumper or not on the fan limit control?

Thanks -- The wiring seems to check out OK. Went ahead and replaced the Honeywell L4064B limit switch with a new one.

This switch has a break-away jumper in it.

How do I determine if I need the jumper or not (already discarded the old switch) ? I have three wires running to the limit switch. Thanks again .

by (mod) - The fan limit breakaway jumper is removed for using the switch on a low-voltage circuit

JW

Handling the breakaway jumper or pull-out tab on a new fan limit control switch:

I don't know which brand and model limit switch you've got but removing a tab typically is for use with low voltage - that breakaway or pullout is explained in the article I'll cite below.

Hop over to FAN LIMIT SWITCH INSTALLATION & WIRING where you'll find installation instructions and manuals for fan limit controls.

About the breakaway tab in our photo above,

Honeywell says:

The brass jumper is the breakaway type. It must be removed when the limit is used in the low voltage circuit.

Details are at HONEYWELL L4064B LIMIT WIRING WHEN CONTROLLING LOW VOLTAGE

 

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