Propex heater ducting with PVC, thoughts?

[JCDriller]

I'm going to be permanently installing my propex 2211 under my roof top tent and I'm thinking about using 2” schedule 40 PVC as ducting instead of the metal ducting it came with as I don't have enough length and it'll likely just get crushed. The propex puts out air around 190*F, well within the PVCs limits. I think I'll be using 2” Shower drains in the floor of the tent to act as the intake and output vents.

 

[Martyn]

I would test the PVC with the heater for a prolonged period of time. Temperature ratings for materials are for a given period of time so the material could fail after extended exposure.

Otherwise looks like a great idea.

 

[WOODY2]

BAD IDEA

 

[Lmg]

PVC Off gassing

BAD IDEA

Agree, Yes, very, very bad idea.

1. Google my title and learn of health concerns related to PVC off gassing which is accelerated at higher temperatures.
2. Ducting should be same diameter as furnished with the furnace, or in some cases larger, the 2" diameter and the drain fitting you are considering will reduce airflow, possibly causing the furnace to overheat and shut down. Propex should have furnished registers, use them.

 

[Semi-Hex]

A shower drain would block a lot of the air flow. That said, there are a lot of insulated ducting materials you could use that are used today for ducting in clean rooms or other applications. I made my duct out of sheet metal and it looks like a small dryer duct through square.

 

[JCDriller]

This is what I was thinking, I'll do more research on the PVC material. The 2" PVC is the same or so close to the propex outlets it's hardly noticeable and the shower drain isn't adding any constrictions. If needed I can do the output hose using the metal propax hosing, and use PVC for the longer intake run. That should be just fine.

 

[JCDriller]

Wow, did some reading heating PVC is bad stuff. I found www.suremarineservices.com and they had ducting in 10' runs as well as higher quality floor vents. I placed an order and I'll return my all the PVC fittings to home depot.

Thanks for the heads up, really appreciate it.

 

[Martyn]

Good idea, good materials that work for your project, sounds like a winner.

 

[Nd4SpdSe]

Ya, I looked into it and ABS to see, cause I'm trying to find a 90 degree fitting for my 60mm Webasto ducting. I honestly had a hard time finding a clear yes or no. There's a bunch of info in regards to it's use in HVAC systems, and apparently popular in Europe. Maybe it's a special version or quality to handle that, but I'm going with a Webasto for the safety, and don't want to poision myself in another manner using something I shouldn't. This however may need more research on this subject.

 

[JCDriller]

Ya, I looked into it and ABS to see, cause I'm trying to find a 90 degree fitting for my 60mm Webasto ducting. I honestly had a hard time finding a clear yes or no. There's a bunch of info in regards to it's use in HVAC systems, and apparently popular in Europe. Maybe it's a special version or quality to handle that, but I'm going with a Webasto for the safety, and don't want to poision myself in another manner using something I shouldn't. This however may need more research on this subject.

$8.30

Webasto W298-49A High temperature 60 mm duct elbow

http://www.suremarineservice.com/W298-49A.aspx

 

[JPShooter]

Not sure what tent you are using, but I was going to go with the same unit but put it under the trailer and duct into the annex instead of the tent.

Of course this only works if you are using a vestibule/annex. These units can easily be remotely controlled (from inside the tent), and since I really don't need much if any heat at night it seems it would be better to bring in the hot air at the ground level and heat the tent via the annex. So when i wake up I remotely turn on the unit and within a few minutes the annex should be a toasty place to climb down into and dress. Of course the heat going into the annex will rise nicely into the tent as well.

That's the way I was going to approach it.

For now I've purchased a "Little Buddy" portable propane heater for the annex, but I have to get out of bed to turn it on.

We are using the largest CVT tent with annex by the way, mounted on an M1101, so mounting under the trailer would be an easy place to put it.

 

[JCDriller]

Not sure what tent you are using, but I was going to go with the same unit but put it under the trailer and duct into the annex instead of the tent.

Of course this only works if you are using a vestibule/annex. These units can easily be remotely controlled (from inside the tent), and since I really don't need much if any heat at night it seems it would be better to bring in the hot air at the ground level and heat the tent via the annex. So when i wake up I remotely turn on the unit and within a few minutes the annex should be a toasty place to climb down into and dress. Of course the heat going into the annex will rise nicely into the tent as well.

That's the way I was going to approach it.

For now I've purchased a "Little Buddy" portable propane heater for the annex, but I have to get out of bed to turn it on.

We are using the largest CVT tent with annex by the way, mounted on an M1101, so mounting under the trailer would be an easy place to put it.

We likely have the same tent, CVT Summit extended Denali. That's a good idea about the annex, but I don't want to have to use the annex to get heat. My tent is set up on a riser platform that lifts the tent 16" to a maximum height of 78" off the ground which is the ideal annex height according to CVT. Due to this I've got a great space under the tent with plenty of room when collapsed to mount the heater there and keep my ducting runs as short as possible. I also plan on keeping the wiring and propane permanently installed, it'll just got up and down with the rack. The thermostat will be hardwired into the tent along with a bunch of other 12v and USB charging ports.

Here is the tent in the travel or stowed position:

Here is the tent in the up position (sorry for all the crap on the trailer, it's a work in progress), the propane heater will be installed to the base of the tent.

 

[Nd4SpdSe]

$8.30

Webasto W298-49A High temperature 60 mm duct elbow

http://www.suremarineservice.com/W298-49A.aspx

No, that is made directly come off the unit at a 90 degree. I need just a regular 90 degree enbow that I can connect between some section of 60mm duct, because the ducting can't flex that tight.

JCDriller, I love the installation idea!

 

[JPShooter]

We likely have the same tent, CVT Summit extended Denali. That's a good idea about the annex, but I don't want to have to use the annex to get heat.

Yes we do have the same tent!

In going the annex route I'm reasoning that if it's cold enough to need heat, then it's cold enough to need the annex for a changing room (camping with wife and daughter). However, as I suspect you well know, the annex is not something you "just throw on" for an overnight stop. It's quite a pain to deal with.

As with everything, it's all a compromise for sure!

 

[JCDriller]

No, that is made directly come off the unit at a 90 degree. I need just a regular 90 degree enbow that I can connect between some section of 60mm duct, because the ducting can't flex that tight.

JCDriller, I love the installation idea!

Just got all my parts in from Suremarineservices.com very fast shipping!

I think this 90* elbow will work for your needs, it is designed to work with the ducting or straight out of the heater.

It actually fits the piping way better than the heater unit. I'll probably insert metal piping into the heater then slide in the elbow.