A few basics...

[fluke77]

Hi,
im new to the trade and understand that for an A/C system at least a 10 degree C TD on indoor and outdoor coil's is an indication of normal operation and 4-8k degrees C subcool and 4-7k superheat.
What are the values for medium and low temps?
Thanks for any help

[Rob White]

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For most systems you'll get by with the same figures.

In the UK we work to about 15 Degs difference over the cond (outside unit)
but that is just splitting hairs.

When you stop working to rules of thumb and start being exact,
the 10 degree rule is not as accurate, especially if you are
working on things like fresh meat. Because a wide Delta T (temp difference)
over the evaporator tends to dry out the meat too much and ruin it,
with fresh meat you might have a Delta T of 2 degs.

In essence your figures are what we use give or take and for the most
part, that will hold true for most types of system, whether low temp, medium or high.

Regards

Rob

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