Using poly pipe as conduit for pex.

[Clutchcargo]

I'm running hot and cold water to our garage from the house. The house is about 14' away from the garage. Is it possible to push or pull 1/2" pex thru the poly pipe? I already have two 1" poly pipes in place for this purpose but 1/2" is a lot less volume for the hot water line and I'm a bit worried about running hot water thru the polyethylene pipe.
Thanks for any ideas and suggestions.

 

[Jeff H Young]

I*d be concerned too using that pipe ,I dont think its approoved for hot water verify that and your fittings, just a sink ? why not try pex 1/2 inch?

 

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[Clutchcargo]

I*d be concerned too using that pipe ,I dont think its approoved for hot water verify that and your fittings, just a sink ? why not try pex 1/2 inch?

The contractor installed water lines from the house and a drain to the house. He talked a good game and I thought that he knew what he was doing but hindsight 20/20.
The first problem that I noticed was that he did the drain pipes incorrectly. The problem was that the pipe needed to be sleeved because of the proximity to our well and he also used an incorrect elbow when transitioning from vertical to horizontal (pressure 90). I cut out the concrete and dug up the drain. Still working on that (VT flooded and derailed a few things).

Now I'm looking at the poly pipes. I have trepidations that it might not be able to handle hot water. They're much deeper and I don't want to dig those up. My solution is to try to push pex through but I want to make sure that what I'm about to try will work and if so... how can I make this easier?

 

[Reach4]

I see no problem running your pex thru the polyethylene pipe.

I find sites that list an upper limit for carrying hot water of 80C (176F) but also some say 140F. I expect your hot pex will not carry water over 140F, but if it did, remember the poly pipe is not under pressure. Plus the dirt it travels thru will somewhat serve as a heat sink. I am not a pro.


https://www.vinidex.com.au/technical-resources/pe-pressure-pipe/pe-temperature-considerations

A Piping Solution for Potable Water | WL Plastics

In use in potable water applications since the 1960s, high-density polyethylene (HDPE) pipe has become the ideal material for piping systems used to transport drinking water.

wlplastics.com

 

[John Gayewski]

I think i would use the cold 1" and use a point of use heater for the hot. Unless there's more hot water demand than I think there is, in this garage.

Yes you should be able to pull 1/2" pex through that. I've pulled 1" pex through 2"conduit. It wasn't easy but it worked.

 

[Clutchcargo]

Thanks all. Is there something that I can lubricate the poly with to minimize the friction between the pipes that will not interact with the plastics?
If this doesn't work for whatever reason, I don't want to damage the poly as it would be the last resort to get water to the garage.

 

[Jeff H Young]

Unless you know something about using this pipe for hot forget about it.
I havent pulled pipe or wire but 5/8 od vs 1 inch od with a guy pulling and someone guiding should go smooth.
this aint rocket science but your construction pro was a bit lacking probebly just a bit clueless in some aspects.
I dont use poly much not so sure its even legal for cold its meant for outdoor use but tecnicaly might be legal with one joint above slab
Nice patch looks like a brand new building

 

[Clutchcargo]

Thanks, the construction pro was a heavy machine operator that installs septic drain fields. I assumed that he had the credentials to accomplish this but I was wrong. This pipe is typically used for well pumps I think he over his skis on a basic plumbing task.

 

[Tuttles Revenge]

We use poly to sleeve lines all the time. Its a great way to run water underslab too if you're daisy chaining your distribution, because you can always pull it out and replace if and when a leak happens... and should prevent most underslab leaks due to a rock creating a pinhole.

 

[Jeff H Young]

I dont want to bash him just one of those things sorry for the issues you had

 

[Reach4]

Thanks all. Is there something that I can lubricate the poly with to minimize the friction between the pipes that will not interact with the plastics?
If this doesn't work for whatever reason, I don't want to damage the poly as it would be the last resort to get water to the garage.

Check out "pulling compound".

To pull, run an electrical snake first. Use that to pull a cord. Now how you attach the cord is going to be the hard part. No need to discuss that, however, because I think you think that running the PEX carrying household hot water thru the PVC is a problem.

Simultaneous pulling and pushing would be good if you were to go through with it, although either may be sufficient.

 

[WorthFlorida]

If your hot water heater is usually set for 120 degrees. It will cool down as the conduit heats up first. I think you're good. For pull glide, in any electrical section will have it. Idea Clear glide is good, just don't get too heavy with it.

 

[Eman85]

How much hot water are you going to use in the garage? I have a point of use water heater under the sink in my garage as washing my hands is all hot water is used for.

 

[Clutchcargo]

The back story is that we're setting up a coffee roasting business out of our house in a relatively new but unfinished garage. We need hot water for daily cleaning of everything. Plus and more importantly, the health inspector will be checking the water temps. The original plan was to put a water heater in the garage but we're focusing on minimizing costs and pipe is cheaper than running gas. Electric is not an option, we have a cap of keeping all the equipment under 50 amps.
I'm discovering the benefits and detriments to not requiring inspections.

 

[Jeff H Young]

Check out "pulling compound".

To pull, run an electrical snake first. Use that to pull a cord. Now how you attach the cord is going to be the hard part. No need to discuss that, however, because I think you think that running the PEX carrying household hot water thru the PVC is a problem.

Simultaneous pulling and pushing would be good if you were to go through with it, although either may be sufficient.

I think using a lubricant on the pex might need verifying that its good for potable water , this probebly sounds over the top but they say contaminants in the ground can some how get absorbed in pex, So whatever goop or powder you use might matter plus it could eat the piping up I wouldnt use petroleum product

 

[Tuttles Revenge]

The back story is that we're setting up a coffee roasting business out of our house in a relatively new but unfinished garage. We need hot water for daily cleaning of everything. Plus and more importantly, the health inspector will be checking the water temps. The original plan was to put a water heater in the garage but we're focusing on minimizing costs and pipe is cheaper than running gas. Electric is not an option, we have a cap of keeping all the equipment under 50 amps.
I'm discovering the benefits and detriments to not requiring inspections.

I've done plumbing work for some big giant coffee roasters and some tiny boutique shops. The last one I did back in 2012 and they're still going! A friend whose wife works at Starbucks corporate went to their coffee shop and was annoyed at the line.. but when he got back to the jobsite, he said it was the best cup of coffee he'd ever had. Their coffee cups are even on my desk as I speak... err.. type.