Need an A/C education please

[48ford]

On my everyday driver(1994 F-250) the a/c is not working good,and i see that the expantion valve is all iced up.
What is the problem and how do I fix it.
thanks Russ&Irene

[HOTRODSRJ]

On my everyday driver(1994 F-250) the a/c is not working good,and i see that the expantion valve is all iced up.
What is the problem and how do I fix it.
thanks Russ&Irene

Usually icing is a sign of low frigerant believe it or not.  I know....most would think the other way around but there is not enough cooling media (refrigerant) to remove heat effectively.  So, ice you get usually inside at the evap.

Does it work just for a matter of minutes then quits?  This is the sign.

[48ford]

Usually icing is a sign of low frigerant believe it or not.  I know....most would think the other way around but there is not enough cooling media (refrigerant) to remove heat effectively.  So, ice you get usually inside at the evap.

Does it work just for a matter of minutes then quits?  This is the sign.

Yes it works but not good.
I will see if it is low on 134.
Thanks Russ&irene

[EMSjunkie]

You might want to check for a
resistance to air flow.
that can cause an icing condition.

possible blocked evap.
i think  :?


Vance

[entodad]

Sounds like low 134a.  There might be no other problem other than low refrigerant because 134a is notorious for migrating through the hose.
(134a is a very small molecule)
Doug

You might want to check for a
resistance to air flow.
that can cause an icing condition.

possible blocked evap.
i think  :?


Vance

[Ed ke6bnl]

On my everyday driver(1994 F-250) the a/c is not working good,and i see that the expantion valve is all iced up.
What is the problem and how do I fix it.
thanks Russ&Irene

Usually icing is a sign of low frigerant believe it or not.  I know....most would think the other way around but there is not enough cooling media (refrigerant) to remove heat effectively.  So, ice you get usually inside at the evap.

Does it work just for a matter of minutes then quits?  This is the sign.

They will ice up when low the pressures get lower and the refrigerant is colder then you loose enough and that ice is gone and it will go off on a  low pressure swith.