How to bleed air lock in coolant system ,no hot air

Rodney, first thing I can think of, the coolant system has an air lock in it. when changing a radiator now a days, the coolant system has to be bled properly for a successful install. Other than bleeding for air, you may have a faulty plugged core radiator. You did plug your fans back in right. links below on how to bleed air from cooling system.
How To Bleed Cooling System EricTheCarGuy

How to Bleed Air From Your Cooling System DoItYourself com

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiOotyLlInLAhVCdR4KHdTpAe4QFggbMAA&url=http%3A%2F%2Fwww.instructables.com%2Fid%2FHow-to-Burp-your-cars-cooling-system%2F&usg=AFQjCNGscHjEvt6J8S0vwf6Ma5PDjplPCQ

bleed cooling system

Could it be the thermostat?

Remove the coolant reservoir cap. fill it 3/4 full. start the car. You will have to run it to operating temperature. When the thermostat opens up, the coolant from the reservoir will start to drop. add more, but only to the hot mark. Reving up the engine will push out air in the system. Once the air is out (you will now as the heater will blower a constant hot air) Check the coolant level again. Fill as necessary.

they refer to the air/fuel sensor circuit and air/fuel heater circuit , the 0125 code refers to engine not getting to operating temperature , so that is why the other two codes are read , check coolant level, if ok check that the thermostat is opening , if it is then you may have an air lock in the coolant system so bleed the system , whilst bleeding get someone to switch the heater temp switch to hot and back to cold a few times as thats where an air lock could easily get trapped

i'd guess at an air lock in the front core , try bleeding the system turning the temp from hot to cold with engine running and while bleeding watch for any drop in coolant level as dont want more air entering the system

Engine or hydraulic system overheating Coolant system low on coolant in 6020, 6030, 6030 Premium, 7020, 7030 and
7030 Premium Series Tractors.

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Symptoms
After several hours of work, warning system indicates hot engine coolant or hot hydraulic oil.
Situation or Problem
Coolant level in reservoir is between the "MIN" and "MAX" range but engine or hydraulic system is overheating.
Summary
Air is entering cooling system, hindering coolant flow. Check coolant level. Fill to the "MAX" line on the coolant reservoir.
Bleeding Cooling System:
The bleed valve (see Operator's Manual for location) on the radiator must be closed when the tractor is operating. Open the valve when coolant is drained or filled. If the bleed valve is left open, coolant will internally bypass between the low temperature circuit and engine high temperature circuit causing overheating. When bleeding the system, open the bleed valve and run the engine with no load for 5 minutes at 1700 rpm. Then shut engine off for 5 to 10 minutes before closing the drain valve. Check the coolant level. If level is below the "MAX" fill line, repeat this procedure until coolant level stays at the "MAX" line.

Check to coolant level after it cools off and check to see if coolant-water mixture is correct. If those are ok. You could have to much air in the coolant system. Most radiator caps will automatically vent the air out of the coolant system. It could be as simple as a coolant cap that gone bad. Or you may have a air bleed valve on it and you need to bleed the air out manually. To bleed it you will have to crank engine and get it warm. Touch top radiator hose to see if its warm. If not then the thermostat has not opened yet. That could also be the problem. After it gets warm open the bleeder valve if equipped and bleed all the air out. Once the steam and hot air from the valve starts to be gone and pure coolant coming from the valve. You have successfully bleed the coolant system. Cool engine back off and check coolant level once more. Hope this helps.

sounds like you have an air lock in the system, look for a bleed screw on hose or pipe.
when vehicle is cold remove coolant resevoir cap and fill with the bleed screw loose until coolant comes out of screw.Then tighten screw refit cap and run engine.
if unable to find bleed screw raise the front of vehicle as much as possible and top up coolant.

Check operation of the heater coolant on/off control valve and operating mechanism.
Check thermostat is installed and working OK - replace if in doubt.
Check if coolant heater supply hoses are warm/hot when coolant valve on.
If hoses are cold (no coolant flow evident) check coolant system is properly filled (bleed system as necessary to remove possible air locks).
If still no coolant flow check heater system for blockage.
If all above ok, check heater unit air control vanes operation.

In my experience with Audis, after any job requiring changing/draining the coolant the car ideally needs to be driven. With the coolant topped up to max drive the car, keep the revs up and shake the car with steering and over bumps where possible. Whatever you do make sure you take at least 2 litres of water/coolant with you, as as soon as the air lock goes, the level drops a lot and quickly. Also keep an eye on the temp gauge and avoid letting it go much over 90 degrees (over 90 on the gauge usually means its well into the hundreds) When you get consistant hot air through the heater, at idle, the level should of settled. If this doesnt work you may have thermostat issues or a blockage. Good luck, let me know how you get on.