Microchannel evap

[BaldLoonie]

I would gather these were on York products, Gary?

[ar_hvac_man]

Worries me a bit ive been setting a ton of York for the past 6 months. No problems so far except for one dry charge that had a leak right out of the box. Tiny nick in the channel which they quickly shipped any paid 4 hrs labor for me to replace

[garyed]

I would gather these were on York products, Gary?

yes - about 3 years old

[hvacvegas]

I stand beside gary on this one.

I think I'm leaning that way too.

Goodman came out with their "smart coil" "technology" making it more "efficient". Aka, cheaper, and harder to charge.

*sigh*

The thing that worries me, is the size of the internal channels. Anyone here have blocked cap tubes?

I see microchannel coils as nothing other than a long series of cap tubes, due to the size of the internal channels.

[garyed]

Another negative is that they don't recommend pumping units down with microchannel condenser coils either.

[ga-hvac-tech]

That evap looks like an atomotive radiator or condensor coil...

[ChrisTechMech]

Another negative is that they don't recommend pumping units down with microchannel condenser coils either.

So we have to recover the refrigerant to repair a leaking lineset? Do they still come pre-charged?

[gravity]

I'm pretty sure if you tried to pump the unit down, the condenser coil wouldn't have enough volume to hold all the refrigerant. you might be able to pump some of it down.

I have also heard these units are critical charge. if there overcharged by 6oz they can trip on high head.

This just isn't a good thing with all the non-skilled hvac guys that dont know how to properly charge a unit and gauges/temp clamps that havent been calibrated for years.

[SBKold]

They got in there somehow.

I think if u were to add any then it wouldn't fit in.

I also think they say don't do it because it would be easy to completely fill the condensor and then be in danger of rupture with expansion just like overfilling a cylinder.

[gravity]

They got in there somehow.

I think if u were to add any then it wouldn't fit in.

I also think they say don't do it because it would be easy to completely fill the condensor and then be in danger of rupture with expansion just like overfilling a cylinder.

good point.

looks like i gotta carry around extra britches and some wipes when these things really hit the market

[craig1]

Do they still come pre-charged?

I have been installing Nordyne units with microchannel condensers for 3 years now and have not had a single problem with them except that in the beginning they were coming shipped with very little refrigerant in them. Some only had vapor. I was concerned that they had leaks. Tech support assured me the problem was they were having trouble getting the full charge into the microchannel coil at the factory.

I filled them up and there were no leaks. They apparently figured out how to jam all the refer in now because they seem to be shipping with something at least close the nameplate charge.


I have not had to pump one down yet, but I suspect it will be a challenge for all but the shortest linesets.

[gravity]

how do these units run craig? what is the common metering device? do the evap coils still get as cold? how about condensers? whats the temp?

[JBM1000]

I've replaced between 25 to 30 leaking all aluminum microchannel outdoor coils under warranty this summer. Its left bad taste in my mouth for microchannel coils. The only reason for using them is to get the same heat transfer with less materials & less freon so its basically cheaper to make the units. I'll stick with the old stuff as long as I can.

Add the fact that Carrier plasters about ten stickers warning to use "Only Water" to clean the cond coil. Guess any Chemicals will murder the coil.