Case studies of mental models in home heat control: Searching for feedback, valve, timer and switch theories

Abstract

An intergroup case study was undertaken to determine if: 1) There exist distinct mental models of home heating function, that differ significantly from the actual functioning of UK heating systems; and 2) Mental models of thermostat function can be categorized according to Kempton's (1986) valve and feedback shared theories, and others from the literature. Distinct, inaccurate mental models of the heating system, as well as thermostat devices in isolation, were described. It was possible to categorise thermostat models by Kempton's (1986) feedback shared theory, but other theories proved ambiguous. Alternate control devices could be categorized by Timer (Norman, 2002) and Switch (Peffer et al., 2011) theories. The need to consider the mental models of the heating system in terms of an integrated set of control devices, and to consider user's goals and expectations of the system benefit, was highlighted. The value of discovering shared theories, and understanding user mental models, of home heating, are discussed with reference to their present day relevance for reducing energy consumption.

Testing for the size heuristic in householders’ perceptions of energy consumption

“…For example, people with higher numeracy skills tend to be more accurate in their judgements of energy consumption (Attari et al, 2010;Schley & DeKay, 2015). Kempton (1986) and Revell and Stanton (2014) also found variation between people in their mental models of central heating systems.…”

“…More recently, Revell and Stanton (2014) showed that householders might hold various mental models of central heating systems that vary greatly from how the systems actually work. As Norman (1983) pointed out, it is not necessary for people to have accurate mental models of a device or system in order to use it but they must have models that produce the result they want.…”

How Influential Are Mental Models on Interaction Performance? Exploring the Gap between Users’ and Designers’ Mental Models through a New Quantitative Method

“…The second branch stepped out of psychology and applied mental models to support better interaction between people and the external world. Typical research interests include the role of mental models in learning and training [12][13][14][15] and using computers and appliances [16][17][18][19].…”

Mental models: Exploring how people think about heat flows in the home

“…Mental models can make an important contribution to improving building literacy [5,6] because they describe people's beliefs about a system, its elements and connections, which guide actions. As people strive to achieve warmth and comfort in their homes, everyday actions contribute to energy use (and efficiency).…”

“…Instead of technical references, drawings expressed the idea of energy being 'magic', energy being everywhere, and drawn elements often related to natural imagery (sun, waves, wind and lightning) but also to infrastructure (pylons). In addition, Revell & Stanton's [6] study showed that people can hold distinct and incongruent models of their heating system. A group of six overseas postgraduates, living in the UK, had incomplete representations of the heating system and bypassed using the thermostat device altogether.…”