YORK YPC Millennium "HOT" leak

[rccutility]

We've got a 4 year old YORK Millennium YPC gas-fired absorption chiller with a hot leak. Testing shows that it pulls in air ONLY when running. Holds rock solid when not running. No leaks in any external piping. Suspect a leak in the Heat Exchanger. Where do we go from here?? Hoping that this doesn't turn out to be a 20 ton paperweight.

[NoNickName]

The pressure only lowers in the evaporator/absorber when the gas burns. I suspect a defective pump seal in the absorbent circuit.