This form is a direct link to our service booking calender, allowing you to book and pay for  a service  appointment for your heat pump  at a time to suit you. All our engineers are experienced engineers  and employed directly by GSM Ltd. Servicing takes approximately 1hr per visit. Our service costs are as follows:-  Air Source Heat Pump   £193.80 Ground or Water Source Heat Pump £237.40  PLEASE NOTE PAYMENT IS REQUIRED UPFRONT BEFORE A VISIT IS BOOKED.  Available service dates are shown based on your postcode, so you’ll only see options for when we’re in your area. This helps streamline our services and reduce our CO₂ emissions