filling radiant floor tubing

[Kapt]

I need to fill my radiant floor heat tubing and figure out what kind of fluid to use. It's a closed system that will require about five gallons. I've read somewhere about RV stores selling a glycol based fluid for RV systems, and I've also heard of people using radiator fluid mixed with water (distilled water?).

Also, how did you get the fluid in and pressurized? My instructions call for a portable 1/2 hp pump which I don't have. I suppose with compressed air I could fabricate something. What have you done?

 

[kbs2244]

Get one of those little pumps with the garden hose connectors.
You will need about twice the fluid you will end up useing.
Get a good sized buclet, 7 gallons is a min, 10 or even 20 better, and fill it with your mix.
You want to **** it from the bucket and push it through your tube and back into the bucket untill you don't get any air bubbles coming out.
Depending on the length and shape of your layout it can take 30 to 45 min. of pumping before you get a clean flow.
You want to do this after all your manifolds and valves are in place so you can turn off each run as you purge it so you don't get air back into it.
I have seen it done useing the systems ciculating pump, but they do not self prime, so you have to have your supply above the pump and gravity feed it to keep it supplied.
For sure you want to avoid any air in the system.
If you push a bubble to the pump it will stop everything.

 

[Kapt]

Get one of those little pumps with the garden hose connectors.
You will need about twice the fluid you will end up useing.
Get a good sized buclet, 7 gallons is a min, 10 or even 20 better, and fill it with your mix.
You want to **** it from the bucket and push it through your tube and back into the bucket untill you don't get any air bubbles coming out.
Depending on the length and shape of your layout it can take 30 to 45 min. of pumping before you get a clean flow.
You want to do this after all your manifolds and valves are in place so you can turn off each run as you purge it so you don't get air back into it.
I have seen it done useing the systems ciculating pump, but they do not self prime, so you have to have your supply above the pump and gravity feed it to keep it supplied.
For sure you want to avoid any air in the system.
If you push a bubble to the pump it will stop everything.

Why do you need so much extra fluid? What type of fluid did you use? Thanks for the reply.

 

[kbs2244]

You need the extra fluid to keep the level in the supply bucket from being lowered so far the you **** air.
It is cheap when compared to have to do the job over again.

The RV vs Auto antifreeze argument is one I want to avoid.
Both side have good and bad points.
I am of the opinion that it dosn't matter much.
Just avoid over heating either of them.
If you have a solar system, shade it in the summer.