Taylor 336 Soft Serve machine mix cooler

[amuthler]

I have been working on this Taylor 336 replacing a Rusted out hopper with a reman. Now the mix cooling system quit working. The constant expansion valve has been replaced but it is either wide open or completely closed. When valve is closed the high side reads 150 psi and the low side has abouy 20 inches of vac. when closed and both are constant at 60 psi when adjusted open. It seems there is no adjustment.

[indy2000]

I assume you are meaning AEV as constant.

The evap pressure rises it closes valve.

The system is critically charged.

Do you have the correct charge?

[Mike19]

I assume you are meaning AEV as constant.

The evap pressure rises it closes valve.

The system is critically charged.

Do you have the correct charge?

Agree, is it the right AEV, the right refrigerant, and the correct charge. When you start to adjust the valve open, does it do nothing, then jump from 20" to 60 on the suction?

[Mike19]

I work on some Taylor Ice Cream machines, not familiar with this particular model. Is the mix hopper refrigerant cooled (did you have to recover refrigerant to change it?) Also, did you put the new AXV in the same time you changed the hopper, or had it been changed earlier?

If so the first thing that pops into mind is either the axv is bad and is sticking one way or the other, or there might be moisture or other contimants that are making it stick. If you had the refrigeration system open to change the mix hopper, did you change the liquid line dryer? The replacement hopper could have some contaminants in it that worked loose and are causing problems.

If you don't have enough refrigerant the head and suction pressures will both be low, but if you turned the axv adjustment clockwise the suction pressure should have gradually increased anyhow. If you where able to back the axv adjustment all the way out and the compressor pumped down, that is a good sign that the compressor is probably ok.

By the way what gas does it use, R12, 502, 404?