As of mid-2019, A.O. Smith has discontinued the BTH 200/201 Series Cyclone Mxi units to its discontinued product line.

This discontinuation includes, but is not limited to the following models: BTH 120(A)-250(A) and BTH 300(A)-500(A) (the full list of A.O. Smith units that are no longer in production can be found here).

The Cyclone Mxi series first started production back in 1996, as a part of A.O. Smith’s ever increasing effort to increase the thermal efficiency of their units via engineering and production methodology. With 95%+ thermal efficiency, A.O. sold over 250,000 Cyclone Mxi units between 1996 and 2015 alone. We typically tend to service these commercial water heaters in various restaurants, salons, spas, medical care facilities, and local businesses across
the Midwest.

What happens if your BTH 200/201 Series water heater breaks down?

In the unfortunate event that your unit is discontinued and not fully functioning, there are still various options for repair: local water heater service providers who stock parts are likely to have many of the common parts (ie gaskets, switches, and gas valves) because of the popularity of these units over the past two decades. As of July 2019, we are currently stocking the majority of replacement parts, from switches to exhaust elbows to the burner and blower assemblies. In the event that your local distributor or service provider is unable to locate the necessary parts, they may recommend other service providers or suggest that you purchase a new unit.

What part of your 200 Series unit should you monitor and why? | No Blower Feedback

The main areas of the unit to monitor are the display, blower, and connections to your water and gas lines. In addition to thermal efficiency, these units have also been engineered to produce user friendly self-diagnostics. The display screen will typically be provide you with the diagnosis to help begin the repair process (whether it is a blower based error code or another error code). We have received several calls for service on BTH 200/201 Series units where the unit’s display read an error code of “No Blower Feedback” or “Low Blower Speed.” In this case, with the blower being one of the most crucial parts on the unit, it must be changed to ensure that the unit will function to its full abilities. Since this is a somewhat common error code, we have also recently increased our stock of these blowers, as locations with these units (especially medical care facilities) may not be able to close down or get immediate approval of the funds required for an emergency water heater changeout. Commercial water heater changeouts may also take over eight hours to complete. | Further information on blowers under the next subheading

It is also important to ensure that your unit’s gas and water connections have solid connections to the unit. In these cases, it is possible that your unit may need to have its connections re-piped, as opposed to requiring parts to be changed or a complete changeout.

General Information on Blowers | Commercial & Residential Units

Power Vent units utilize blowers to propel the exhaust (gas biproducts produced when the unit is active) out through the venting system. You can find more information on venting terminations with real examples of customers before/after photos here. The way your unit was installed is crucial to its functionality! Your unit’s intake must be a certain distance from the exhaust (exact distance is specified in the unit’s installation manual). If the intake is too close to the exhaust, your unit will be recirculating the exhaust gases, possibly leading to premature Hot Surface Ignitor (HSI) failure (HSI: the “spark plug” of the water heater; its point of ignition). In addition, it is also important to monitor your unit’s flame rods, which can bend as a result of delayed ignition or gas pressure. 

Due to the large amount of rain the Midwest has received over the last few months, it is also important to consider examining your unit’s venting from the outside. If there is not a proper vent termination kit, condensation and rainwater may be seeping directly onto your blower! This is also possible if the termination is not properly angled, as seen in this article. Moisture can cause the blower motor bearings to squeal, eventually causing permanent damage.     


If you have concerns about your unit’s venting and/or parts for your BTH 200/201 Series unit(s), please call us at 1-877-879-4776 for availability and pricing