Checking on progress at new house and see this ones insulated with the foam. Can't pull service loop out at doors or windows. Luckily I was out of 3/8" plugs when I pulled the wires and had left 4"-6" of wire tied in a knot at every window. But for future I gotta come up with a new way to leave a service loop on prewires with this foam insulation. Once that stuff dries you can't pull wires out! Glad I went by so i could dig a little room out before window trim goes on. Coil up right under hole? Any ideas?
I've been on many service calls with sprayfoam & 3/8 recessed contacts on all the windows & doors. Sometimes these foam guys are on a crusade of somekind. There have been times that I could not pull the service loop out, not matter how gentle I was. I wasn't able to get enough wire to use a screw terminal contact, let alone reach the beanies.
That's why I like to use surface contacts on all the windows. At least you can cut off the leads and easily place a terminal contact. Placing a piece of PVC pipe in the door header to protect the wires makes it easy to get to the beanies. On service calls however, we generally replace bad contacts with terminal screw types, for speed and for future service.
If you know they're going to use foam insulation, install 3/4" contacts. Strip back about 10-12" of the outer jacket from the cable and coil up the inner conductors in the 3/4" hole beneath the contact. There will be enough space in the hole to pull the wires out. If any foam comes in contact with the wires, use a long pair of tweezers or a needle nose to gently work them loose. Although acetone will melt foam insulation, it can also damage the PVC insulation (it's used as a solvent to melt PVC).
Side note: Although I haven't tried it, one fellow I know says he puts a bit of cable pulling greases on the wire to keep the foam from sticking. The stuff doesn't hurt PVC so it probably works but I'd test it before relying on it.
I can understand a larger contact on doors but how do you drill a 3/4 inch hole in the sill of a window and maintain integrity of the weather strip?
Also, it seems to me that I remember seeing a foam solvent on the shelf at Home Depot. Not too sure about that because I wasn't looking for it. But if they have it, you might want to take a look and read the lable or try some on a sample of wire. If it's got acetone or methal ethal keytone, it'll melt the wire insulation.
Here's another thought. Presuming you're using jacketed four wire ......
When you install the wire where the foam will be put try this: About six to eight inches from the end of the wire, start to strip the jacket off but don't take it all the way off the end of the wire. Make sure the jacket is loose on the four strands. Leave about an inch of the four strands showing and put the end of wire through the hole just long enough so that the four exposed wires are a few inches below the hole and tie a knot in it. Cut off the excess insulation at the end of the wire. After they foam, I'd think if you pulled on the insulation, that you would stand a good chance that the insulation would come off the four strands from where you'd left the gap.
I really don't know if it would work or not as it was just a thought I had. You'd have to try it. Seems like it might work though. Likely you'd still have to dig some of the foam out of the hole but at least you'd have enough wire to work with.
Here's another thought. Where you start to strip the insulation ..... pull two of the wires back out of the insulation and wrap them back down the wire from where you stripped it, leaving the remaining two conductors (now loose) inside the insulation to the end of the wire. Tie a knot outside the hole. Later when you pull on the insulation, is will likely break free of the foam and leave the two strands available and loose in the foam.
Again, you'll have to experiment. I've never tried this.
And then when you need to replace the switch? What then?
3/8" | >plugs when I pulled the wires and had left 4"-6" of wire tied in a knot at | >every window. But for future I gotta come up with a new way to leave a | >service loop on prewires with this foam insulation. Once that stuff dries | >you can't pull wires out! Glad I went by so i could dig a little room out | >before window trim goes on. Coil up right under hole? Any ideas? | | | You're using plugs? Damn man just put the freekin contact in @ | prewire to save a bunch of grief. | | I haven't had that much trouble with the foam, if any is in the way I | can usually scrape it out with a small screwdriver. Someone mentioned | acetone would melt the foam, I've never tried that. | | -- | | -Graham | | (delete the double e's to email)
Day before yesterday we had started a big rough-in, then it got too dark to work, we had drilled out the entire house and had pulled about 50% of the wires...went back in the morning to finish up and these screwballs had foamed everything including our holes we hadn't used yet...I went off on these Russian electricians...dunno if they knew what I was saying but I think they got the gist of it. I usually leave a BIG note at the front door...DO NOT FOAM OUR HOLES...we will stuff them with insulation when we're done! In English & Spanish, now it looks like I have to add Russian.
| >>Checking on progress at new house and see this ones insulated with the | >>foam. | >>Can't pull service loop out at doors or windows. Luckily I was out of | >>3/8" | >>plugs when I pulled the wires and had left 4"-6" of wire tied in a knot at | >>every window. But for future I gotta come up with a new way to leave a | >>service loop on prewires with this foam insulation. Once that stuff dries | >>you can't pull wires out! Glad I went by so i could dig a little room out | >>before window trim goes on. Coil up right under hole? Any ideas? | >
| > You're using plugs? Damn man just put the freekin contact in @ | > prewire to save a bunch of grief. | >
| > I haven't had that much trouble with the foam, if any is in the way I | > can usually scrape it out with a small screwdriver. Someone mentioned | > acetone would melt the foam, I've never tried that. | >
If it won't pull out easily, or I break the wire -- then it becomes a repair job. I'll usually then just drill a hole straight down the wooden sill and fish the wire up and surface mount the new contact.
Houses are so poorly insulated here that we don't run into the foam issue very often.
I try to always use 3/4 or surface but couldn't use 3/4 on these windows and didn't want to use surface because of the way this window is built. These were the Vetter windows from a previous post about a month or 2 ago when I inquired on how would you drill these windows.
Don't be fooled with silicone. Though it is a great water sealer, it doesn't last forever. I have pulled contacts from sills just to find the silicone breaking down due to exposure, this is one reason why we don't install contacts on sills anymore. I have seen mold growing near the baseboards, under & on the carpeting, under the sills, usually near the contact. So you can imagine the damage behind the walls...
Once the silicone breaks down, then its just a matter of time before the contact housing cracks. I have found water, and rotted leads from installs from just 5 years ago. I made Ranger American aware of this, since they were usually the company that did most of the prewires in my area. I also did alot of trimouts & service calls for them, so that made it easier for them to listen to my concerns.
Since then, they only use surface contacts on windows, and only use recessed on the doors & patio sliders. This eliminated the problem altogether.
It depends on the way the weatherstrip is designed. If it's on the lower sash rail, use a 3005 and you don't have to touch the strip.
Another possibility where there is a recess in the lower rail of the sash, if the sill isn't mucked up with a huge weather strip (some have the strip affixed to the sash and only have a small ridge on the sill) is to use a rare earth contact like the GE / Sentrol 1075R. The magnet is about the size of a large shirt button and can often be seated in the recess. In some windows I've been able to slit the weather strip, insert the magnet behind (above) it and replace the strip with a dab of silicone. Since this doesn't require drilling the sash it's not likely to cause problems though a manufacturer could conceivably use it as an excuse not to honor the warranty. I've never had a problem doing it that way but you might want to verify with the manufacturer before using the method. Some are more flexible than others.
Almost all of those solvents will also attack the wire jacket. Consider testing it on a wire sample for a few days before using it.