Install the Pressure gauge BEFORE the expansion tank not AFTER

Awesome thank you!! Getting ready to do my pole barn floor system! A lot of helpful information!!!

The pressure tank pressure is supposed to be set to be equal to the system pressure. They usually come from the manufacturer set at either 20 or 40 psi. But imagine if your system pressure is around 18-24 psi, but your tank is at 40 psi. That would just mean that it would take more water expansion before the tank would start performing. In your case, the pressure woud theoretically rise to above 40 psi before the tank would start working. So, you need to get that tank bladder pressure down to whatever the system operating pressure is. That way, if the watrer expands to increase pressure to above system pressure, the tank will take that extra water and regulate it back to the system pressure. It looks like you have a couple of isolation valves on either side of the Pressure tank, so that can help you set the bladder pressure of the expansion tank.

Nice!!! do you get pipe noise (tapping, scratching, popping) due to pex expansion and being tight in the groove?

What liquid do you use in your system, glycol , windshield fluid?

Good job brother 😊

7:14 Instead of 15 psi, you need to ask if she is 18 psi. Not that I have a chance in Hell.

You should not use household water in the closed system.

Looks great, I recently purchased a house with radiant heat. I love it and am in the process of learning. Mine has two separate zones, first and second floor. The second floor manifold has an automatic bleeder which is located above the entire system and air bleeds easily. However ky first floor manifold is in the crawl space and I have had an issue with air locking as the return pex is below the floor system. Have you had any issues with air since your system is located below the floor it’s heating? Or do you have a way to bleed the air from above?

How do you fill the system?

Because it is a closed loop system and hopefully it was filled with a mix of polyethylene glycol and DISTILLED water you shouldn’t have to clean it at all. Now, the polyethylene glycol mixture may have to be replaced every five or 10 years per mgr instructions that I am not sure about. The reason why tankless water heaters need to be cleaned when they are used for domestic hot water is because of all the minerals that are in normal water but using distilled water there shouldn’t be any minerals at all. Thus no need to flush your tankless water heater.

For a DIYer, this is a solid effort. I had my friend - a licensed HVAC - help build my system. The only thing I would caution you on is the flow direction of your pump. If its pumping downward, it may be flowing at a higher rate than you intended. Also was told that it will shorten the life of the pump so may be worth looking into. Otherwise, looks good and thanks for sharing.

I think in your case it doesn't matter which side the pump goes in. I am building a hydronic snow melt system for my driveway, where the slab temperatur could be 10 degrees or even cooler. Pumping a mixture of glycol and water would make the liquid too cold for having the pump on the cold return. I will place it on the hot supply (which would be about 15-20 degrees warmer than the return). Not sure if anyone can comment on this.Thanks!

This is awesome. I'm wanting to do this also.

So as far as the expansion tank goes, they are usually factory charged around 15 psi. When your system is running, the tank does nothing. When the system is static the expansion tank uses the diaphragm and trades air compression for water thermal expansion. Another way to think of it is static you may have 15 psi, running you may have 13 psi and thermal expansion may raise your static to 17. When the tank goes bad you will see the 30 psi pressure relief kick and you should replace both parts when that happens. Pump push or pull won’t matter with hydronic/radiant since that pump is probably rated to run at about 180 degrees. I would humbly suggest you turn the temp up to at least 120. Radiant works best with a slightly higher delta t (temp difference) and the warning you are looking at is more about prevention of scalding for a water heating system not a system limit and not what you want for a delta in a heating system. Install looks great, hope you get years of life out of it.

Here are your typical pressures for a low temperature hydronic heating system...... Cold Fill Pressure = 15psi Expansion Tank Pre-Charge = 12-15 psi Pressure when system running and up to operating temp = 20-25 psi Pressure safety valve should activate at 30psi A system pressure of 15psi is more than enough static lift to get water up to the upper floor.

Nice job, can you tell us what you did for a cooling?

The pump goes in the return line because it is cooler. This will make your pump last longer.

Great video! Can you shoot another video after you make the added parts you and others have discussed.the supply/heating and manifold is where I'm at. I just started researching using a tankless heater and came across your video. This looks simple and to the point not overwhelming as some of the videos out there thank you.what is you gpm from the heater?

Nice video. Do you use just the floor heating in the rooms that have it? And if so how has it been in the winter. I have radiators and I’m wondering if there still necessary

You are using a water heater relief valve that is set at 150 psi. You need to change that to a boiler relief valve which is set to blow at 30 psi. If your water heater would stick on you would split your PEX, destroy your expansion tank and circulator. Always install a expansion tank valve between your tank and your system, this will allow you to remove the water pressure from your tank without opening your system to check the air pressure yearly in your bladder.

Wow definitely not professionally done. Pipes not level, no real support and your pumps going to burn out fast as your pumping water through the whole system off one pump. Should have primary line and have the manifold off a secondary line.

I'm from Chicago as well. I'm considering installing similar system and retrofit it into existing slab.

Thanks for the video. Would you be able to also list where you sourced the materials from in the video description next to the price breakdowns you already show? I'm not sure if you mentioned it in the video, but I didn't catch where you purchased the Ecowarm Boards from.

The expansion tank has an air bladder in it that you pressurize via the schrader valve on the bottom of the tank. As your system generates heat, the fluid expands, which would increase pressure in the system if there wasn't some way to modulate that -- that's what the expansion tank does. When the fluid expands (by being heated) the pressure goes up in the system, which pushes against the air bladder in the expansion tank, thereby increasing the volume within the system so that the pressure decreases to whatever you're trying to keep it to. Conversely, if the fluid cools (like if you had the temp set to decrease overnight), the fluid volume would decrease, so pressure in the system would drop; the air bladder in the expansion tank then pushes back against the fluid in the system and helps increase the pressure to your desired setting. Clever devices and they just automatically adjust based on the pressure you set in the air bladder.

Hi great video, what size is your boiler, thinking of doing a system very similar many thanks

That thermal expansion tank is normally pre-charged from the factory at somewhere between 12 - 15 psi because it should roughly match the cold (non-operating) pressure of the fluid in your heating loop which typically would be in that same range. You can always check the air pressure in the expansion tank with an air gauge for a bike or car tire. Make sure the system is cold first to ensure you get a correct reading on the tank pressure...

Normally hydronic systems have a one way fill valve like a Watts 911S. This would ensure that your heating loop maintains the required pressure and fluid volume (in case of a small leak somewhere etc). This would also remove the need to connect a garden hose to flush the sediment trap since the fill valve does the same thing. Is there a reason why you don't have this type of valve installed?

Looking to do this in a 900 sq ft cabin. Curious costs? Also curious on solar panels, how many?

I have questions.. what was the Sq. of your radiant floor and how much was the total cost of building radiant system?

Great video !

Nice job! Appreciate the overview. It doesn't matter if your pump pushes water on the hot side or pulls water on the return side for radiant floor heating. For hydronic radiators, the circulator pump is on the return due to higher water temperatures.