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humblepie
18-08-2009, 03:49 PM
I think I have a clogged cap tube. I have low head pressure and low pressure is in suction. If so how hard and what is the easiest way to replace. I have not do one before. Any help would be greatful.
Thanks Wade

acnerd
18-08-2009, 04:49 PM
I think I have a clogged cap tube. I have low head pressure and low pressure is in suction. If so how hard and what is the easiest way to replace. I have not do one before. Any help would be greatful.
Thanks Wade

The capillary tube would generally have a strainer before it in the pipework. It's not always that obvious as it's not necessarily a "bulge point" on the pipework. The easiest is to un-braze the capillary and blow through to see if it is clogged. You may have to cut a bit of the pipework before the capillary out to clean the strainer off, which is more likely the problem.

Incidentally, if you have low head pressure and low suction pressure, aren't you just short on refrigerant? Capillary systems are charged based on superheat, so what is your superheat value? I'm sure the clever boys will correct me, but I think you would have a high subcooling value as you back liquid up into the condenser if the capillary is blocked.

chemi-cool
18-08-2009, 05:58 PM
Which refrigerant?
What kind of machine?

More details will help us to help you.

udarrell
18-08-2009, 06:38 PM
I think I have a clogged cap tube. I have low head pressure and low suction pressure. If so how hard and what is the easiest way to replace. I have not done one before. Any help would be greatful.
Thanks Wade
What was the superheat & Subcooling temps? In F for me, in USA.:D

Suction & head pressures, both LOW:

SH 'High', low charge or possible restriction; SH 'Low', insufficient airflow or heatload through the cooling coil.

We, & you, both need a lot more test data. - udarrell