My airflow valve is pouring water out on spa - Kohler K-1110-AH-0 Purist whirlpool with Spa Experience, White...

check inline filter or check to see if hose is collapled sometimes the bend where they go into the polaris

put a valve on that hose and shut it so you dont loose water you have a weak multiport gasket you should be ok for a while

The wagon wheel looking spider gasket inside the has bit the dust. Depending on your valve model you may be able to just replace the spider gasket. Some manufacturers don't offer the gasket as a stand alone part and you have to replace the diverter assembly. If you post your valve model, i can send you a link to the proper part.

This gasket usually goes out because someone lifted the handle on the valve while the pump was running. Be sure the pump is always off before pressing down on the handle to change positions.

depending on the plumbing you might have to cheat the out put actuator to put some water in spa when in pool mode

Low water volume will cause low pressure. Check for any obstructions in the suction libe and/or minor leaks that will cause the pump to **** air. If everything checks out, make sure the water is actually flowing thru the sand. If you suspect the water is bypassing thru the multi-port valve or a tunnel in the sand: pour a cup of flour in the skimmer, if you see it return thru the returns, you have your verification.

This is an ether or situation. Most systems now are set up with three way valves and if you turn the jets on you will shut the pool returns down. If you turn the pool back on you will shut the spa jets off.

There should be a rubber "O" ring in there. Check for that

This is tough cause I can't see the valve setup. I have to assume they are manual valves. Normal operation probably takes some water out of the pool and spa than puts it back into both. To heat the spa, set the intake valves(the ones in front of pump) to take water from only the spa. Set the jets(valve(s) on output side of filter) to send water back to only the spa. The pool will be out of the loop. Normal operation usually has water taken out of pool and spa than put back into both. Make sure to put more water back into spa than you take out, (Adjust valve)

waooo is gues su have a leak if the heat exchanger is leaking this may be due to a low PH level on the water? if the leak is at the fitting than replace the fittins

replace the pressure guage.
prime the pump by pouring in water in the impeller basket area and replace lid-try running pump again