Now thats hotgas defrost for ya!

[Tycho]

http://www.4shared.com/dir/3920216/8...c/sharing.html

Hope this works... if it does, you should see a .MP4 file, download it an play in quicktime, not sure if it works in mediaplayer.

[Brian_UK]

Sorry Tycho, the link goes to the page but says that the link is not valid.

Want to try again ?

[Tycho]

Sorry Tycho, the link goes to the page but says that the link is not valid.

Want to try again ?

Sorry about that, here's alink that should work.

http://www.4shared.com/file/24547966...092007010.html

*Note* I did not get sound when viewing the file on the page. Also found out you can play the movie in mediaplayer

[US Iceman]

I have to agree. That is how hot gas defrost should work.

What type of system was that exactly? I have not seen that before.

[Brian_UK]

Boy, that's quick for sure.

[Tycho]

Boy, that's quick for sure.

hehehe, not easy to see, but the ice is actually thrown from the collector

Automatic defrost with danfoss PM valves. this one wasnt as bad as the other two freezers, preassure form 0 to 9 bar with a bang... quite an adrenaline rush

[SteveDixey]

Heh Heh! Great stuff! Problem is anyone not used to it tends to suffer from "stomach trouble" when that happens and calls out engineers from the safety of the factory gatehouse...

My last job had PM3's set at 6 bar in Gyrofreezers. Problems was we couldn't convince people it was safe so we ended up just opening freezer doors and running fans

Steve

[US Iceman]

Tyco,

I think you might want to look at using an outlet pressure regulator in the main hot gas line to reduce the hot gas pressure down to a lower value during the initial defrost cycle. That reduces the chance of pressure shock and the loud noises.

It will also calm down the people close to the unit when defrost starts!

[Tycho]

Tyco,

I think you might want to look at using an outlet pressure regulator in the main hot gas line to reduce the hot gas pressure down to a lower value during the initial defrost cycle. That reduces the chance of pressure shock and the loud noises.

It will also calm down the people close to the unit when defrost starts!

I've told them many times but "It's always been like that"

My suggestion was to open the hotgas PM and delay the closing of the suction PM with 5-10 seconds.

The way it is now, it closes the suction, all the while pumping liquid into the freezer, then opens the hotgas 5 seconds later.

Don't need hydraulics, just up the hotgas pressure and the frozen blocks will jump out of the freezer

[US Iceman]

Don't need Hydraulics, just up the hotgas pressure and the frozen blocks will jump out of the freezer

Yep, I'm sure you are close to the truth with this comment. You could use this as a training area for new refrigeration people.

When the loud bang occurs, those still standing close to you should get the job! Those that ran off should continue to keep looking for a job since they are the nervous type!!

[Brian_UK]

There's someone asking about defrost systems just now...
http://www.refrigeration-engineer.co...ead.php?t=9602

Should we point him to this thread or would that be unkind?

[smpsmp45]

This is really fantastic. If we show this to our clients, they shall insist on having a system like this!!!!