Hi have no hot air what so ever heater matrix changed and aux heater and waterpump still no hot air

Repair facilities don't "give up" - not sure what's going on here, unless what is happening is considered normal. If you have no hot air, there is a reasonable reason for this that can be checked and verified and rectified. Seek a second opinion at another repair facility near you.

Hi, Here are some ideas which may be helpful for you: 1. Replace heater core. 2. Replace thermostat twice and water pump twice. 3. Replaced heater hoses. 4. Jacked the front end off the ground and tried pressure burp as you have. 5. Replaced reservoir tank and cap.