When people install a new pellet stove, one of the first questions they have is whether or not they can use a computer UPS, or uninterruptible power supply, to run their appliance in the event of a power outage. Many pellet stove owners’ manuals will say that the answer is yes, but there are some risks and considerations associated with this practice that every pellet stove owner needs to be aware of.
Responsible manufacturers familiarize customers with backup risks
Just one example of this practice is illustrated in Harman® pellet stove owners’ manuals. Harman specifically instructs users to install a battery back-up. The exact wording states:
“Harman strongly recommends installing battery back-up to minimize entry of smoke into the room in the event of power loss […] Your pellet/biomass burning appliance relies on a combustion blower to remove exhaust. A power failure will cause the combustion blower to stop. This may lead to exhaust seeping into the room. Vertical rise in the venting may provide natural draft. It is, however, no guarantee against leakage.”
Harman® recommends two battery back-up options, one of which is a UPS that is available online or at computer and office equipment stores. If you decide to go with this option, keep the following in mind:
Use the recommended brands and models
Just because a UPS works with a computer, it cannot be automatically deduced that it will drive the combination of motors present in every pellet stove. Often, pellet stove manufacturers test and approve certain brands and models of UPS for compatibility with their stoves and may recommend certain ones. If you should choose to use a product other than recommended, you run the risk of incompatibility between the stove and the UPS. This can result in damage to your stove requiring costly repair. Don’t accidentally fry your control board.
Use a UPS for shut-down only
A computer UPS to power a pellet stove will provide little backup time. There will be a finite amount of time (approximately 15 minutes ) during which you will be able to run your stove. For this reason, Harman® specifies that the UPS provides safe shut-down only. It is not intended for continuous use. In other words, a UPS will give you just enough time to properly shut down your appliance in order to minimize smoke generation during a power loss.
This is a fine solution if your home has an alternative heating source or if the power outage only lasts a short period of time. But if you still need to heat your home via pellet stove, you will not be able to do so with power supplied by a computer UPS.
Remember that shutting down your stove is still a manual process
With the limited amount of time your stove will operate on a UPS battery backup, you need to start shutting down the unit quickly if the power goes out. But keep in mind that the stove can’t communicate with the UPS, so the shut-down process will not begin automatically. It still requires manual interaction from you. Imagine the power going out in the middle of the night. If you do not wake up during the time your UPS is capable of supporting normal operation your stove will continue to run for a few minutes and then abruptly shut off. Make sure you are familiar with the dangers of losing power to your pellet stove before you make your battery back-up decision.
Don’t get complacent about your safety and that of your home by assuming that a few extra minutes of power will always be sufficient to escape the occurrence of smoke damage. You should be prepared for the worst-case scenario. A more reliable solution for pellet stove battery back-ups is an automatic battery backup, designed for use with a deep-cycle battery that can operate your stove for hours. Learn more here.