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Posted: Sep 15, 2010 02:46 PM	Iso hose flushing Soooooo, we left one of our units for too long with out using it (about 2 months) and now I can't spray 1 min until I go off ratio and the Iso screen in the gun block packs solid with Crystals. I have circulated the iso (through a filter and back into the barrel) for hours and still am getting clog ups. There is great flow through the line now. Air must have been getting in somehow through the gun block as the iso first came out like molasses and slowy got better. Also there was quite a bit of air in the line (last 50' + whip). I think there has been a post on here before about this, but I can not find it, sooo what are my options. Pump MEK through the lines? other type of solvent? pump lube? Gas and a match?
SprayFoamSupply.com Posted: Sep 15, 2010 08:22 PM	I have cleaned quite a few machines and hoses with iso crystals. The walls of the hose get a layer of ISO build up like a clogged artery and then break off piece by piece in what seems like an endless supply. Recirculating solvents do nothing to break up the crystals as nothing dissolves or even softens crystalized iso, nothing we have found anyway. We use surf-x-flush to clean our parts and flush iso, but whatever the solvent is is irrelevent so long as it is compatable. Depending on the length of hose that you have, put 3-4 gallons of solvent into a clean 5 gallon pail. Turn hose heat on to 80-100 depending on solvent. Put on coveralls, respirator, gloves, eye protection, etc. Remove gun and open fluid valve. Have someone hold it over another empty bucket with a screen over it so that you filter the iso that comes out. Pull drum pump out of drum just enough so that the bottom of it is above the level of iso in the barrel and turn on air supply to drum pump. Let drum pump cavitate 10 times then shut off air, this puts an air bubble in the line. Wipe off drum pump and put into bucket of solvent, turn air back on. This will use the solvent to push the iso out of the hose that you are filtering through the screen into the clean bucket. Depending on length of hose, you should get 1.5-2.5 gallons of iso into the bucket before you get the air bubble. As soon as the line spits, you need to close the fluid valve. What you have in the bucket up to now is just iso, not iso blended with solvent, pour back into iso drum to reuse. Now take a new bucket and pour off about a quart, this will be a blend of iso and solvent that will need to be disposed of. Take the screen off of the iso bucket and put it over the solvent bucket. Now you are going to recirc the solvent out of the bucket, though the system, through the screen and back into the bucket. While you are doing this, you will need to have your entire hose spread out on the ground. While one person is holding the hose in the bucket, have one or two others work the rest of the hose. Pick it up and flex it back and forth as much as you can without the risk of kinking it. Bend it, bang it on the ground, smack it, kick it, just beat the heck out of it! Crysallized iso is very hard, but also very brittle and it will crack and break up. You will see the iso crystals in the screen. Keep this up until the crystals stop coming. Could take 2-4 hours or more. Repeat proceedure in reverse to refill system with iso and save the solvent for reuse. Even after all this, check your gauges often. If you see the A gauge going up 200-300 psi, stop and clean your iso gun filter. You could have a few more crystals, but should be minimal. Please let me know how you make out! George Spanos Spray Foam Distributors of NE Inc 603.348.8880
Yvan Richard Posted: Sep 15, 2010 10:42 PM	I was reading your question and noticed that you have some old foam. I have a set that is approx 1 yr old, it is roofing foam. I was going to use it in my personal residence (garage attic). What are the risks of me using this foam, will it be hard on my proportioner? Should I put it through a filter first?
SprayFoamSupply.com Posted: Sep 16, 2010 01:28 PM	Has the iso been sealed tight and stored at a constant temperature. If so, you should have no issues. If it has not been sealed tight, then you could have some excessive crystals in it. If there are, then you need to run it through a screen to filter the crystals out. Should be no risks to your proportioner so long as there are not many crystals. If you are going to be spraying down on the attic floor, you will need to go slow. Older material will react slower and it would be easy for you too put too much on at a time and get some charing. George
Daniel X Posted: Sep 16, 2010 08:49 PM	Is it 3lb. roofing foam? I just sprayed 1/3 of a set of 12 month old 3lb. in a crawl space, before I switched into a brand new set. I find that this 3lb. is a bit slower overall but the old stuff was especially slow. I imagine it's lost a bunch of blowing agent over the last year or so. It was stored indoors capped off, but that's still 2/3s of a drum of air inside. I imagine also if you did a density test on the old roofing foam you would be getting really heavy results, but if it's for your own home and you know you're making "good foam", I'm sure it should be fine. I've dealt with iso crystals in an old rig that wasn't used often enough before, but I've never had it so bad that I had to flush the entire hose out with solvent. I just had to clean my inline screen and my A side screen on the gun every 1000 strokes or so.

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Comments

Posted: Sep 15, 2010 02:46 PM

Iso hose flushing

Soooooo, we left one of our units for too long with out using it (about 2 months) and now I can't spray 1 min until I go off ratio and the Iso screen in the gun block packs solid with Crystals. I have circulated the iso (through a filter and back into the barrel) for hours and still am getting clog ups. There is great flow through the line now. Air must have been getting in somehow through the gun block as the iso first came out like molasses and slowy got better. Also there was quite a bit of air in the line (last 50' + whip). I think there has been a post on here before about this, but I can not find it, sooo what are my options. Pump MEK through the lines? other type of solvent? pump lube? Gas and a match?

SprayFoamSupply.com

Posted: Sep 15, 2010 08:22 PM

I have cleaned quite a few machines and hoses with iso crystals. The walls of the hose get a layer of ISO build up like a clogged artery and then break off piece by piece in what seems like an endless supply. Recirculating solvents do nothing to break up the crystals as nothing dissolves or even softens crystalized iso, nothing we have found anyway. We use surf-x-flush to clean our parts and flush iso, but whatever the solvent is is irrelevent so long as it is compatable. Depending on the length of hose that you have, put 3-4 gallons of solvent into a clean 5 gallon pail. Turn hose heat on to 80-100 depending on solvent. Put on coveralls, respirator, gloves, eye protection, etc. Remove gun and open fluid valve. Have someone hold it over another empty bucket with a screen over it so that you filter the iso that comes out. Pull drum pump out of drum just enough so that the bottom of it is above the level of iso in the barrel and turn on air supply to drum pump. Let drum pump cavitate 10 times then shut off air, this puts an air bubble in the line. Wipe off drum pump and put into bucket of solvent, turn air back on. This will use the solvent to push the iso out of the hose that you are filtering through the screen into the clean bucket. Depending on length of hose, you should get 1.5-2.5 gallons of iso into the bucket before you get the air bubble. As soon as the line spits, you need to close the fluid valve. What you have in the bucket up to now is just iso, not iso blended with solvent, pour back into iso drum to reuse. Now take a new bucket and pour off about a quart, this will be a blend of iso and solvent that will need to be disposed of. Take the screen off of the iso bucket and put it over the solvent bucket. Now you are going to recirc the solvent out of the bucket, though the system, through the screen and back into the bucket. While you are doing this, you will need to have your entire hose spread out on the ground. While one person is holding the hose in the bucket, have one or two others work the rest of the hose. Pick it up and flex it back and forth as much as you can without the risk of kinking it. Bend it, bang it on the ground, smack it, kick it, just beat the heck out of it! Crysallized iso is very hard, but also very brittle and it will crack and break up. You will see the iso crystals in the screen. Keep this up until the crystals stop coming. Could take 2-4 hours or more. Repeat proceedure in reverse to refill system with iso and save the solvent for reuse. Even after all this, check your gauges often. If you see the A gauge going up 200-300 psi, stop and clean your iso gun filter. You could have a few more crystals, but should be minimal. Please let me know how you make out!

George Spanos
Spray Foam Distributors of NE Inc
603.348.8880

Yvan Richard

Posted: Sep 15, 2010 10:42 PM

I was reading your question and noticed that you have some old foam. I have a set that is approx 1 yr old, it is roofing foam. I was going to use it in my personal residence (garage attic). What are the risks of me using this foam, will it be hard on my proportioner? Should I put it through a filter first?

SprayFoamSupply.com

Posted: Sep 16, 2010 01:28 PM

Has the iso been sealed tight and stored at a constant temperature. If so, you should have no issues. If it has not been sealed tight, then you could have some excessive crystals in it. If there are, then you need to run it through a screen to filter the crystals out. Should be no risks to your proportioner so long as there are not many crystals. If you are going to be spraying down on the attic floor, you will need to go slow. Older material will react slower and it would be easy for you too put too much on at a time and get some charing.

George

Daniel X

Posted: Sep 16, 2010 08:49 PM

Is it 3lb. roofing foam? I just sprayed 1/3 of a set of 12 month old 3lb. in a crawl space, before I switched into a brand new set. I find that this 3lb. is a bit slower overall but the old stuff was especially slow. I imagine it's lost a bunch of blowing agent over the last year or so. It was stored indoors capped off, but that's still 2/3s of a drum of air inside.

I imagine also if you did a density test on the old roofing foam you would be getting really heavy results, but if it's for your own home and you know you're making "good foam", I'm sure it should be fine.

I've dealt with iso crystals in an old rig that wasn't used often enough before, but I've never had it so bad that I had to flush the entire hose out with solvent. I just had to clean my inline screen and my A side screen on the gun every 1000 strokes or so.

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