dreaded LG

[marc5180]

been called to a fault on a unit today in a classroom with many computers for the kids. Checked the controller which was set on cooling 18 deg. Checked the air off temp which was 38deg:eek: . went outside and checked the condensor and found it half covered in a block of ice, i know the correct charge is in it because one of the other engineers had fixed a leak on it last week. am i right in thinking that its the reversing valve thats the problem but if thats the case then why would the condensor coil ice up?

[Latte]

Marc,

Welcome to the LG World :eek:

Sounds like the 4 way valve is stuck on heat.
Check that the solenoid coil is not engaged, easiest way undo the screw in the middle and see if it comes straight off, if it does and there is no feel of magnetic pulling then this would rule out a control fault

What happens is when there is a gas leak (normally on the suction side) air/moisture/dirt gets pulled into the system. An engineer somes in repairs the leak but the 4 way valve get jammed. Try tapping the 4 way see if it shifts and feel the pipes only two should be hot, the one coming in and the one going out of the unit on the liquid pipe (Smaller Diamemter of the two coming out the unit)
If the others are hot and the larger pipe out of the unit is warm the valve is stuck.

in answer to youre question to why the condenser is iceing up is that its on heat mode (reverse cycle) so the condenser is acting as an evap does on cooling but the unit is not switching off.
You could try reclaiming gas, blowing through with OFN, Fit Bi-direction drier, Good Vac (With a Torr/Micron gauge) fitted and recharge but i hate to be the bearer of bad news but you will probably need to fit a new 4WV
not a nice job :eek:

Regards

Raymond

[marc5180]

thanks for the reply rdocwra, i took the solonoid coil off and it did feel like it was engaged. when you say its not a nice job to change a 4way valve, why is that. i looked at it before and thought it wouldnt be that difficult..am i wrong?:confused:

[Shakey]

No you are not wrong, 4 way valves are relatively easy to change, just make sue that you wrap the NEW valve tightly with a wet wrag so that it is not damaged during the brazing process.

[chillin out]

when you say its not a nice job to change a 4way valve, why is that. i looked at it before and thought it wouldnt be that difficult..am i wrong?:confused:
Yes!!!

What an absolute pain in the a$$ they are to change, on any a/c unit.

Sounds like the kids or staff have been messing with the controller and set it on heating.
I had a system once that when on heating (outdoor unit being an evap) the outdoor fan would stop for no reason causing it to ice up.

Chillin:) :)

[taz24]

thanks for the reply rdocwra, i took the solonoid coil off and it did feel like it was engaged. :confused:


If the coil is energised then the valve is not faulty.
The problem is the thing is set to heat mode or something has failed on the controler. A probe or something and it is trying to achieve an imposible temp.

Cheers taz.

[marc5180]

If the coil is energised then the valve is not faulty.
The problem is the thing is set to heat mode or something has failed on the controler. A probe or something and it is trying to achieve an imposible temp.

Cheers taz.

yes the valve was energised but it was in heating mode not cooling mode