The following situations may apply to repairs/upgrades:
1. Decrease in vacuum degree/decrease in pumping volume/decrease in outlet pressure
2. The pump produces special noise
3. Pump stuck/pump not starting/pump running abnormally/pump stopping during operation
4. Single and double pump head upgrade/safety diaphragm upgrade/replacement of vulnerable parts upgrade/replacement of motor upgrade
Repair instructions:
To ensure prompt resolution of maintenance projects, please follow the following instructions:
2. Prior telephone communication is required for repair, and a preliminary assessment of the repair is conducted. We confirm and agree that the recipient can send it back;
3. The cost of product maintenance shall be borne by the customer, as detailed in the cost list;
4. The transportation costs incurred during maintenance shall be paid by both parties after agreement (or default to be paid separately by the sender);
5. Without consultation, we refuse to accept any COD goods returned in any way;
6. The repair shall include a complete return authorization letter and any supporting documents and accessories related to shipment.
Note: Please print and sign the authorization letter below, stamp it with the official seal, and send it together with the goods! 

维修与升级授权表