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Andrew Pribora
01-11-2004, 02:13 PM
Hi 2 all!

If I choose an evaporator (dry expansion) and get surface reserve 50%. Is the value of surface reserve good or critical and very bad?


BR

Andrew

frank
01-11-2004, 09:31 PM
Hi Andrew


If I choose an evaporator (dry expansion) and get surface reserve 50%.

Surface reserve is not a term I am familiar with - has your meaning been lost in translation ?

Do you have any other ways of asking?

eggs
01-11-2004, 10:53 PM
is it reserve as in "area" maybe
nature reserve (area)
wildlife reserve(area)

just my initial thought.

cheers

eggs

shogun7
02-11-2004, 05:10 AM
[QUOTE=Andrew Pribora]Hi 2 all!

If I choose an evaporator (dry expansion) and get surface reserve 50%. Is the value of surface reserve good or critical and very bad?

If by surface reserve you mean that the evaporator will be greater capacity then the condenser then I would suggest to you not to do it because a mismatched system will result in a drop in efficiency, in addition, if one coil is changed and its replacement is either smaller or larger than the remaining coil, the charge and expansion device may need to be adjusted in order to keep from flooding or starving the coil. In severe cases, a lack of superheat results in floodback to the compressor, which can cause compressor failure and coils that are not optimized will not remove the amount of moisture they should, therefore sacrificing comfort as well as efficiency. :rolleyes:

Andrew Pribora
02-11-2004, 12:53 PM
I mean by "surface reserve" - greater capacity of ev.

But I don't agree with necessivity of matching "evaporator-condenser" - we use mulltiset and in such case it is not important.

My opinion - it is not critical (in reasonable limits!).

Gary
02-11-2004, 05:38 PM
The evaporator TD is the difference between the refrigerated space temperature and the temperature at which the refrigerant is evaporating (saturated suction temperature aka SST).

Enlarging the evaporator coil reduces the TD by raising the saturated suction temperature (SST).

The coil outlet superheat cannot exceed the TD, because the TEV sensing bulb, which is contained within the refrigerated space, can be no higher than the refrigerated space temperature.

Given the higher SST and low sensing bulb temperature, the TEV cannot be adjusted properly, because the TD is insufficient.

RogGoetsch
03-11-2004, 08:00 AM
I mean by "surface reserve" - greater capacity of ev.

But I don't agree with necessivity of matching "evaporator-condenser" - we use mulltiset and in such case it is not important.

My opinion - it is not critical (in reasonable limits!).

My opinion is the same: not critical within reasonable limits.

But what is "mulltiset"?

Rog

Peter_1
03-11-2004, 10:44 PM
A central pack with several evaporators.