Introduction Systemic sclerosis is a connective tissue disease associated with significantly impaired hand mobility, which may hamper activities of daily living. The aim of the present study was to investigate the effect on hand mobility and health status of patients with systemic sclerosis of warming up hands with paraffin compared with warming up hands in lukewarm water prior to hand exercises. Methods Patients were allocated to receive either warm-up treatment with water or paraffin prior to hand exercises for a period of six months. Primary outcome was Hand Mobility in Scleroderma (HAMIS), while secondary outcomes included SF-36 and measurements of fingertips to proximal and distal palmar crease. Follow-up assessments were conducted 3, 6 and 12 months post baseline. Results Ninety patients were enrolled in the study and 56 patients completed. No statistically significant differences were observed between groups regarding hand mobility post intervention. Within both groups, hand mobility improved on the HAMIS six months post baseline with −2.6 points (95% CI: −4.4; −0.8) in the paraffin group and −3.3 points (95% CI: −5.2; −1.5) in the water group. Improvements were maintained at 12-month follow-up. Conclusions Our findings suggested that warm-up with paraffin compared to lukewarm water prior to hand exercises in patients with systemic sclerosis had no additional effect on hand mobility. Results may have been affected by the high dropout rate and statistical errors underestimating a possible effect.