Warm Kop Grasweg is pleased to help you via the customer contact centre of InWarmteYou can always ask a question by emailing us. We can also be reached by phone during office hours.

Phone: 085 – 004 43 76

E-mail: for general enquiries:

technical questions: 


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A malfunction always comes at an inconvenient time. Please check our Malfunction page first to see if we are carrying out maintenance on your installation or are already resolving the malfunction. Is there nothing online? We would like to solve your malfunction as soon as possible. Call 085 - 004 43 76 (local rate) and indicate that it concerns a malfunction. We are available 7 days a week, 24 hours a day.

Small and other malfunctions are best reported by emailing to

Please note: 

  • During office hours (Monday to Friday from 9.00 to 17.00) our customer service will assess the problem together with you. If necessary, we will instruct our maintenance party to fix the problem.
  • Outside office hours, reports are accepted by our emergency services. If your malfunction is not urgent, our breakdown service will accept the report and our customer service will contact you the next working day.

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You can submit your application for our heat supply through the registration page.

Are you moving? You can unsubscribe from our heat supply via the move out page.


Further questions?

For other questions or remarks, please send an email to

Our postal address is: 2e Daalsedijk 6a, 3551EJ Utrecht.


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