Yet another furnace age question, Old Airco

[howardpike]

I always hate to see that done because it cuts the filter surface area in half (less than half). If they're using a pleated filter with fine media in it, that reduction in surface area can throw up a high static pressure across the filter and cause the furnace to run hot.

Jim, you are right, of course, but when this model was going through certification, the 12" x 16" x 1" filter was within a few square inches of the requirements for airflow. Because it was a downflow and air conditioning was so sparse up here, the supplied filter was only designed for the heat-only application. The manufacturer at the time could have upgraded the filter to a washable foam variant that on paper showed a greater airflow capacity than the fibreglass filter but was in reality denser and more restrictive. They/we chose to go with the custom-made filter plus the side filter in order to meet the rules.

In the field, we regularly changed the filter to the single 12x16 fibreglass and have seldom (read, never) seen them plugging up between annual checkups. We monitor the temperature rise and find no issues with the filter change whatsoever. Even dirty filters are not putting the furnace anywhere near its limit point. The reduced filter size has had no negative effects for our customers.

Those pleated filters, however, were never certified for use in any furnace back in 80's and 90's. I doubt if they are now. Unless they are watched closely and changed often, they will kill a perfectly good furnace. Hopefully, the furnace airflow is balanced with a dirty pleated filter in place. Ideally, the filter system is replaced with a wider version, complete with a bigger and better filter flame.

[Red89GT]

Thankyou for taking the time to share your knowledge

[HeatherB]

The WBS2 is a reliable furnace with quality parts and a good design. It is a "standard efficiency" model with a rated AFUE (Annual Fuel Utilization Efficiency) of 55%. However, if the furnace is in a dedicated furnace room off the garage, as many are here in the Lower Mainland, the off-time losses are considerably reduced. This furnace is one worth keeping until the heat exchanger shows signs of rusting and pitting at the top of the clamshells.

Thank you very much for your detailed response. I had the furnace cleaned and they couldn't tell me there where two filters.

What we are looking to do is to move the furnace from the closet in the house to mount it horizontally in the crawl space. It is a small house and we need the room. I will get someone to take a look for the pitting/rust that you mentioned to see if it would be worth moving this furnace or buying a new one. I estimate this one to be around 26 years old.

Much appreciated.

[howardpike]

What we are looking to do is to move the furnace from the closet in the house to mount it horizontally in the crawl space. It is a small house and we need the room. I will get someone to take a look for the pitting/rust that you mentioned to see if it would be worth moving this furnace or buying a new one. I estimate this one to be around 26 years old.

The Airco/Olsen WBS2 is a naturally-aspirated, downflow gas furnace. It is only approved for an upright installation in the orientation that it is currently working; that is, with the blower at the top. There is no way that it can be mounted horizontally. Besides being contrary to the specifications on the Rating Plate, it would be extremely dangerous.

The WBS2 is an old furnace design with no other installation options.

[Murray G]

I have a question about a WBS2-90 furnace apparently installed new in a condo completed in 1990.  During the installation a custom sheet metal flue was constructed from the top of the furnace via a 180 degree turn to the floor where fresh enters through from more custom sheet metal in the crawl space to intake grills in the house.  Whatever filter arrangement there was in the original furnace design is provided now in a single 18" x 12" x 1" slot at the top of the  custom sheet metal flue just as it turns 180 degrees into the furnace intake.  I have not been able to find filters to fit the slot.  I am using a 12' x 16" filter now but there a lot of leakage around the filter.  Suggestions please?

[Marc]

12 X 18 X 1 air filter

[Murray G]

Thank you Marc!

[raymond c]

i have a airco brand furnace model no. 85 AGH serial no. 8D-33. 

it recently started making a loud buzzing noise for about a minute and stops and repeats when the heat is turned on. 

i have read the past comments and believe the motor is done, we are considering replacing this furnace with a new furnace but i would like to get some advice.

the motor is an 1/4 HP GE Belted Fan Motor MOD: 7J401AS1 

Any idea where i could purchase this motor or if i could use a similar motor to replace the furnace with?

Thanks,

Ray from Vancouver

 

[Marc]

Isn't there a fan relay between the fan/limit control and the motor?  Relays make humming noises when the magnetic faces become too corroded to make good contact.

[Ben L]

Airco TH-130 Serial TU3-1082
What can you tell me about reliability of this furnace?

Presently inducer air blower getting noisy and I'm looking to replace but getting horrendous quotes of around $500 just for the blower, would install myself.  Looking on Amazon.ca found blower that appears to have the correct rotation and RPM, and physical layout looks similar, for $210. Thinking of trying it, only question is air switch connection - one is in blower discharge into the vent and the other in vent housing a few inches above. Blower photo doesn't show side that connection should be.

[Marc]

4 hours ago, Ben L said:

Airco TH-130 Serial TU3-1082
What can you tell me about reliability of this furnace?

Presently inducer air blower getting noisy and I'm looking to replace but getting horrendous quotes of around $500 just for the blower, would install myself.  Looking on Amazon.ca found blower that appears to have the correct rotation and RPM, and physical layout looks similar, for $210. Thinking of trying it, only question is air switch connection - one is in blower discharge into the vent and the other in vent housing a few inches above. Blower photo doesn't show side that connection should be.

I'd stick with getting an exact replacement part.  Keep shopping.

[Jim Katen]

Why not just replace the bearings on the existing motor? 

[Marc]

13 hours ago, Jim Katen said:

Why not just replace the bearings on the existing motor? 

Aren't they bushing bearings?  Can't replace them because you can't locate new ones.

[Jim Katen]

45 minutes ago, Marc said:

Aren't they bushing bearings?  Can't replace them because you can't locate new ones.

Never seen a bearing that I couldn't replace. 

[John Kogel]

Maybe Howard is still around. Go back to page 1, read what he says and try his contact info.

$500 for a blower that fits versus $200 for one that probably doesn't fit and if made to fit, will leak or won't do the job. Just pay the money and get the right one. I know money is tight for most home owners but there are some places where cutting corners doesn't pay.

I think 1082 is a 1982 unit, so it's had a good run and is still worth a repair.

Edited October 13, 2019 by John Kogel

[Phil101]

Hi all,

I stumbled across this amazing forum. I too have an Airco furnace that I'm looking for info on. From what I've read so far from previous posts, I assume with my specs below that mine is an upflow 2 burner built in Dec. 1977? 

Brand: Airco

Model: AH-90

Serial: U2-1277 

 

[Marc]

8 hours ago, Phil101 said:

Hi all,

I stumbled across this amazing forum. I too have an Airco furnace that I'm looking for info on. From what I've read so far from previous posts, I assume with my specs below that mine is an upflow 2 burner built in Dec. 1977? 

Brand: Airco

Model: AH-90

Serial: U2-1277 

 

Seems correct.

[Zaphod]

I've got an Airco AH-130 in the house I recently bought in Edmonton, AB.  The furnace tech I had do the inspection says the heat exchanger is rusting(though no apparent holes) and we should replace the furnace.  Now it is old, and probably dates back to construction in 1975. But personally I'd prefer to keep this thing, as I don't trust the new high efficiency models to last more that 10 years, and with problems at that.  I've asked a couple places for a quote to replace the heat exchanger, and am told that parts aren't available.  What I'm wondering is if that's legitimately true, or if they just want to sell me a new furnace.  Anyone able to tell me if there is a place to get parts for these things?

[John Kogel]

Read all three pages of this thread and you will know more than you do right now.

Howard Pike, Chimo (Cheemo?) Heating services, Coquitlam , BC, hasn't been checking in lately.

Good bet you are SOL for a new heat exchanger for a 1975 Airco, but check the date code from Howard's info. The newer owner of the company was Olsen, an they probably stopped stocking parts for the older models. I don't know this, just a guess.

Rust on the outer surface doesn't mean the heat exchanger is leaking. Was there an actual gas leak, or flames escaping?

[Jim Katen]

On 11/29/2019 at 1:21 PM, Zaphod said:

I've got an Airco AH-130 in the house I recently bought in Edmonton, AB.  The furnace tech I had do the inspection says the heat exchanger is rusting(though no apparent holes) and we should replace the furnace.  Now it is old, and probably dates back to construction in 1975. But personally I'd prefer to keep this thing, as I don't trust the new high efficiency models to last more that 10 years, and with problems at that.  I've asked a couple places for a quote to replace the heat exchanger, and am told that parts aren't available.  What I'm wondering is if that's legitimately true, or if they just want to sell me a new furnace.  Anyone able to tell me if there is a place to get parts for these things?

That 1975 heat exchanger probably had rust on in in 1976. The mere presence of rust on a 45-year old furnace means little. I wouldn't condemn it for that alone. 

There's no way you're going to find a new heat exchanger for that furnace. When that heat exchanger goes, the furnace will then be scrap metal.  

[ejager]

Inspecting just a bit to the south (Calgary), I can tell you that I have seen many many new high efficiency furnaces that have been operating for almost two decades already. Admittedly things have change since the first iteration of furnaces were put on the market, one of the most significant being installers learned they needed to read the new instructions because things were different!

There's lots of competent companies out there. Find one that has been in business since before these economic doldrums and has a proven track record. They won't install a garbage unit and they'll do it right. If you don't trust them, get a third party inspection after install before you make payment.

[richard hargreaves]

good morning I have an old but very reliable Airco Furnace model WBS2-90, I need to replace the filters in the unit but I cannot locate where they are.  Any clues

Thank you Richard

[Jim Katen]

7 hours ago, richard hargreaves said:

good morning I have an old but very reliable Airco Furnace model WBS2-90, I need to replace the filters in the unit but I cannot locate where they are.  Any clues

Thank you Richard

The filter (or filters) will be somewhere in the return air stream - they could be anywhere. Start at the furnace's blower compartment and work your way back to the return-air grille. If you don't find the filter, hire an HVAC contractor to install a filter housing for you. 

[Ramona R. Stults]

I have an Airco AH-130 in the house I as of late purchased in Edmonton, AB. The heater tech I had do the assessment says the warmth exchanger is rusting(though no clear openings) and we ought to supplant the heater. Presently it is old, and presumably goes back to development in 1975. In any case, actually I'd want to keep this thing, as I don't believe the new high productivity models to last more that 10 years, and with issues at that. I've approached a few spots for a statement to supplant the warmth exchanger, and am informed that parts aren't accessible. What I'm thinking about is whether that is truly valid, or on the off chance that they simply need to sell me another heater. Anybody ready to let me know whether there is a spot to get parts for these things?

[Marc]

delislej said:

 

I have an Airco Model AH-75 serial 1F3-97 or IF3-97. Any idea on age?

Name plate appears to be a label and not metal, and has more information than the 60's ones I see here. The house was built in 1967 I believe, and the furnace looks original.

 

 

Quote

 

The furnace was indeed built in September of 1967, so it is the original.

 

As you've read in the previous posts, this model of furnace has an excellent life expectancy - 60 years. And, it is trouble-free. The chance of you have a life-ending failure is remote, but if you've got the money and are investing in the future of the house, then it's as good a time as any to upgrade.

 

However, if you are thinking of replacing it because "it's old", or "it's got a crack in it", or "it's very rusty", then get a second opinion.

 

Other than a hole in the heat exchanger or a burner damaged beyond repair, everything else on the furnace is a fairly low cost and straight-forward repair.

 

I dragged this old post out of the trash heap.  Your model is a higher btu/hr rating and different serial but I think this post may help guide you a little in deciding whether to trash your Airco or keep it. The response to delislej is by Howard Pike, who has posted here many times and whom I regard as the member most familiar with Airco heaters.

Edited February 22, 2020 by Marc