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Draft Inducer Cross Reference Guide
Find the Correct Replacement with Our Draft Inducer Blower Cross Reference Guide
Draft inducer blowers are original equipment manufacturer (OEM) replacements used in furnaces and water heaters. They are a shaded pole or permanent split capacitor (PSC) motor-driven small blower wheel assembly. Because draft inducer blowers are considered critical components, they should never be a replacement part that you randomly select.
Since government-mandated efficiency standards were enacted in the furnace industry, draft inducer blowers have become a common replacement part. Since furnaces are being designed with specific blowers, it is very important to use exact replacements that match the original blower for safety reasons.
View our expanded line that includes 14 new drop-in OEM draft inducer blower
Requirements of Proper Draft Inducer Blower Replacements
Proper draft inducer blower replacements are designed to meet OEM specifications and are then tested to match OEM performance requirements. They must effectively move the hot flue gases and combustion by-products through the heat exchangers and out of the house or building. Beyond the obvious need to withstand flue gas temperatures up to 450 degrees Fahrenheit, the unit must mount correctly on OEM equipment and the blower housing and impeller must be made of materials that can withstand the corrosive chemical compounds present in flue gas.
Other not so obvious factors also exist:
- OEM exhaust coupling design has a strong influence on air flow rates and pressures which could have upstream impact on burner efficiency and deadly carbon monoxide creation
- Improper airflow rates can impact the function of the pressure switches and other safety device
The Issues with Copycat (Non-OEM Approved) Designs
In many cases, copycat designs that are reverse engineered have shown in lab testing to be inferior, as these alternative manufacturers are not privy to all the details and lab testing that went on in OEM product development. Therefore, they shouldn’t be trusted as equals to OEM approved replacement parts.
These non-OEM approved “copycat” induced draft blowers can provide a pressure signal capable of closing a switch which then allows gas to flow. However, the pressure signal is only an indicator of the airflow. The OEM’s true design actually requires a specific airflow (CFM). The OEM has modeled the inducer blower to give a pressure signal as an indicator of airflow for their design only. A pressure signal in a reverse engineered induced draft blower does not guarantee proper airflow that is sufficient for safe operation.
Low airflow can cause condensation in places the furnace manufacturer did not intend. Corrosive compounds in the flue gas then “rain out” acidic condensates, which may attack furnace materials and might even eat through heat exchangers. The furnace manufacturer intends that the walls of the heat exchangers remain intact for safe and proper operation. A compromised heat exchanger can both create and propagate deadly carbon monoxide gas.
A copycat draft inducer blower that delivers too much air flow can cause combustion air temperatures in the system that are higher than the furnace manufacturer intended, which could result in over-heated furnace components and in turn a shortened component life. On a two-stage furnace, insufficient draft inducer airflow on low-fire can cause the pressure switch to open, which tells the furnace control to run on high-fire. This results in poor efficiency. A copycat inducer draft blower with marginal performance on high-fire can cause nuisance trips and even a lockout until reset.
In addition to the issues outlined above, a copycat draft inducer blower is not approved by the OEM for use on the system and makes the appliance non-compliant with the OEM’s original agency approval. This can cause problems for both contractors and their customers.
The Bottom Line for Contractors
As a contractor, your goal is to restore the equipment to full and safe operating conditions. While we all understand that managing your parts costs is a critical part of business survival, there is potential for harm if using any “equivalent” induced draft blower instead of an OEM approved part. This could include:
- Harm to your bottom line due to call backs and insurance claims
- Harm to your reputation through customer frustration with lock outs and early equipment failure
- Bodily harm to the occupants or family by carbon-monoxide poisoning or other safety concerns
At the end of the day, using cheaper replacement parts might end up costing you more in the long run. Instead, take the time to select the correct replacement part using our new Draft Inducer Blower Cross Reference Guide (link).
Using the Draft Inducer Blower Cross Reference Database
We have created a Draft Inducer Blower Cross Reference Database to help contractors select the correct product. Since we build the original draft inducer blowers for OEMs, we can sell the exact same parts, which have been tested and approved for the original manufacturers in the first place.
In order to find the correct replacement, you will need to locate the model number on your original draft inducer blower. Once you have your model number, use the Cross Reference Database (linked below) to find the correct replacement part.