This paper describes an evaluation of five machine learning algorithms for predicting the domestic space and hot- water heating production for the next day. The evaluated algorithms were the k-nearest neighbour algorithm, linear regression, regression tree, decision table and support vector machine regression. The hot water production was measured in the ME3Gas project, where data was collected from two Swedish households that use the same type of geothermal heat pumps for space heating and hot-water production. The evaluation consisted of four experiments where we compared the regression performance by varying the number of previous days and the number of time periods for each day as input features. In the experiments, the k-nearest neighbour algorithm, linear regression and support vector machine regression had the best performance.