PVC, freezing weather

[jmellc]

I've used various PVC heater boxes over the years and found them mostly OK, some have a few quirks but doable.

This week, I was using one for 4 inch PVC in 27 degree weather. I recently used the same box for 2 inch in milder weather with no issues. But I had a lot of trouble with the 4 inch. DId the usual trick of rags in each end to cut cold air flow, kept turning pipe every few seconds, etc. It's 4 feet long but wouldn't heat 4 feet of the pipe, only about a 1 foot section in a "hot spot". Took forever to heat enough length for a good bend. Also kinked a couple of pieces really badly.

I'm sure the weather was the main issue. If I have to do this again, maybe I'll try blowing through with a heat gun to give extra heat. What have any of you tried in freezing weather?

 

[hbiss]

First time I heard of rags. I have plugs with an air fitting on one. I pressurize to about 10 PSI from an air tank equipped with a regulator and gauge. Then you have to rotate and move the conduit in the hot box to evenly heat it. This way it will not kink. I agree that it would be a good idea to do this someplace where there is no wind. Also, make sure the voltage is correct at the hot box. Generators and long extension cords can result in a low voltage and lower heat.

-Hal

 

[hillbilly1]

I use duct tape, the heat expands the air inside and helps keep it from kinking. I have used the heating blankets, they work real well on the bigger stuff.

 

[jmellc]

First time I heard of rags. I have plugs with an air fitting on one. I pressurize to about 10 PSI from an air tank equipped with a regulator and gauge. Then you have to rotate and move the conduit in the hot box to evenly heat it. This way it will not kink. I agree that it would be a good idea to do this someplace where there is no wind. Also, make sure the voltage is correct at the hot box. Generators and long extension cords can result in a low voltage and lower heat.

-Hal

This was powered by a generator with a 25 foot cord. Same as I’ve used before but with smaller pipe & in milder weather. I doubt I can get bosses to buy an air compressor but I can see how that would help. I’ll check voltage next time.

 

[jmellc]

I use duct tape, the heat expands the air inside and helps keep it from kinking. I have used the heating blankets, they work real well on the bigger stuff.

Duct tape sounds good. I’ll try that. We have a blanket but not big enough for 4 inch.

 

[mopowr steve]

Use that salamander heater probably right next to you instead.
Rotate with some back and forth motion

 

[Hv&Lv]

3“ & 4” I have filled the pipe with sand and taped the ends shut. It keeps the pipe from kinking and the bend can get pretty tight with that method.