In between the four group cleanings, individual stoves got mini cleaning consisting of a simple burn pot scrape only if the stove would not relight and could not be tested. Individual cleanings were recorded and totaled for each stove. We observed that the stoves with the smaller sized burn pots (Ravelli, Englander, Piazzetta) required much more frequent cleaning than the larger stoves, 2 of which that had automatic cleaning systems (Enviro, Quadra-Fire). The ones with automatic cleaning systems, the Enviro and Quadra-Fire did not need or receive any individual cleanings, and may not have even needed the routine group cleanings that we provided. The Piazzetta received the most individual cleanings followed by the Englander. Since the Piazzetta could not be tested the fourth week, an average of each week’s number of individual cleanings (approximately 1.5) was used for the fourth week to provide a cleaning score that was equivalent to the other stoves.

Our testing resulted in the need to clean some of the stoves much more than others, partially a result of the type of pellet we used. An expensive, 100% softwood pellet may have shown that none of the stoves we tested needed much cleaning. We used a pellet that is relatively typical of medium quality pellets that are widely available in the eastern US, with 0.5 to 0.6 ash content. Had we used a lower quality pellet, cleaning would likely have been required even more often.