Links to the other two videos are in the description! This is a three part video: Part 1: ua-cam.com/video/y7SZPfXn2w8/v-deo.html Part 2: ua-cam.com/video/Eawgtg4V7tA/v-deo.html Part 3: ua-cam.com/video/qwoeAWtTvXI/v-deo.html
Wow Benjamin I have placed pex tubing in my 3 car garage slab and just getting around to configuring the heating portion, hence the reason i found this video. Additionally, i have a Mitsubishi I-miev and a off grid solar system.. Apparently we have a few common interests ;) Rock-on
Great job. One thing I think would've done to improve the system is to place the tubing on a floating shelf of metal reinforcing wire to sit in the middle of the concrete slab. That way the heat is distributed closer to the top of the slab where it's benefiting you the most. The boiler would also require a lower max temp to achieve the same result. All this goes out the window however if you were drilling in multiple spots of the concrete slab for shelves/car lifts, etc.
Thank-you for this great 3-part video. The insulation goes under all the concrete, both the slab and the foundation? How is the insulation on the side of foundation protected from the elements, or from getting chipped away? Thanks!
The insulation goes under the slab, and around the edges of the slab, with a thermal break between it and the foundation wall. The exterior of the foundation wall is covered in foam. (I don't recall how thick. 3/4", I think.) The exterior foam is then covered with a metal mesh, and that was covered with a concrete in sort of a stucco finish. Foam on the outside of a building definitely needs to be protected.
There are several different styles of systems. Some of them just use tap water and ARE designed with a connection to city water. This is NOT like that. It's a sealed system using glycol. No water connection is needed.
Looking forward to part2. 26000 btu is quite a bit I can heat my garage with about 15000 which is a 4500 watt electric heater my garage is 28x30 which is fairly big. The heater can make it 80 degrees in winter and I am at 45 degree latitude is it does get cold.
26,000 BTU was a quick estimate of the heat required for a space this size. The actual heater itself produces a peak of around 24,000 BTU. That also doesn't mean that the heater actually outputs that much constantly. The heater throttles down it's power once the return water starts warming up. A big part of BTU ratings is about how FAST you can heat a place. Given enough time (and insulation) even a very small heater can heat a large space. Frankly, this was the lowest power micro-boiler I could find! Once the space is warmed up, it doesn't take much heat to keep it warm, but it's a fairly significant amount of work to warm up the large concrete slab in the first place.
Seems to work fine. Keep in mind that I'm not trying to heat to 70 degrees 24/7. Just bring it up to 50 or so in the winter. I've really had no issues with this system. I typically just flip the heat on the night before I'm working in the garage.
Great video and wonderful details. How would you compare the heating you used vs. a chiller heat pump with a variable compressor which runs on electricity for space heating, space cooling, and hot water. A few brands doing this are Multiaqua, Chiltrix, and Daikin. Sanden does a good job too; however, they only do space heating and hot water.
I couldn't tell you how it compares exactly, because I don't have a heat pump. And even if I did, I'd need to have it hooked up to this system to give a truly proper comparison. This is just a resistive heater. The best part of heat pumps is that they are several times more efficient than resistive electric heat. However, air-to-air heat pumps only work well down to a certain temperature and then often switch to a backup resistive heating element anyways. My master plan is to use a wood-burning boiler or some other alternative heat source as part of this heating system.
BenjaminNelson thank your response. I spent a little bit of time this morning trying to analyze this. Your system is superior to all others due to heating up the large mass of the slab. Cost wise I got different answers. For all I added up equipment cost, energy cost, maintenance cost, and hot water cost, and I ran these costs for at least 10-years. The conventional AC is the most expensive. The next most expensive are heat pump chillers. Despite their higher efficiency when you have several rooms their cost adds up due to requiring several outside units as well as several inside units, and the outside units are expensive. For a single room like your garage connected to a radiant hydronic slab it could make sense depending on the COP, the input kWh, and the source of energy. The cheapest for a multi room use are solar AC units which run directly off solar panels, have a COP above 3, and consume on average around 0.6 kWh. A wood or pellet boiler could make sense.
If you don't want to fight the pex when unrolling than you just leave the whole roll wrapped in the plastic wrap. Remove the end from the center of the roll and pin it down with a heavy object, and then just unroll it where it's needed.
Hi Ben, thank you for very informative video. I have a question: Did you calculate the benefit of solar PV electric heating vs. solar thermal for your hydronic system? From efficiency view, it is better to go with the second. Thank you!
If a person were purely to look at heating from an efficiency point of view, YES, solar thermal is much more efficient than converting sunlight to electricity with PV and then using that to heat. However, I can make and use electricity year round (and use it for lighting, power, heat, whatever I want,) whereas solar thermal heating is only appropriate for part of the year. Beyond that, when I need heat the most, the sun is at the worst position for it. I would want very steeply angled solar collectors, which does NOT match the pitch of my roof. (The garage is the only practical location for solar in my yard.) Solar thermal collectors on the roof would take up space that could otherwise be used by my PV. Frankly, I LIKE how the PV looks on the roof, and it would NOT look as good if it had to miss a few PV panels to have solar thermal collectors there instead. Since solar thermal would be best at a steep (even vertical) orientation for winter heating, I instead chose to make one of my garage doors directly into a solar collector. It still looks nice and is functional, and doesn't require any pumps or tanks or even air vents. See the video on the Passive Solar Garage door at: ua-cam.com/video/EcuRfnP6E7I/v-deo.html
The 7kW is fine. I was never trying to heat my garage to 70º 24/7. I just wanted to have it be warm enough in the winter to work in a sweatshirt or light jacket, instead of freezing in the driveway like I used to. The concrete slab is a significant amount of mass. If I want to warm up the garage from unheated, I definitely turn on the heat the night before. The next morning, I can turn it off, and the heat will continue to raise through the day. It works pretty well if I'm going to be working in my garage all weekend in the winter. The other thing is just having the garage well insulated makes a HUGE difference! I'll just turn on the heat every once in a while and it stays above freezing pretty much all winter. Even when there's pretty large temperature swings between day and night, the temperature stays really consistent in the garage. The combination of thermal mass and good insulation works great. I also installed a glazed door I designed to let in the sunlight (and heat!) on sunny winter days. ua-cam.com/video/EcuRfnP6E7I/v-deo.html
@@BenjaminNelsonX I designed my system kind of like yours (Thank you for the video), but i just got it going but i used a hot water tank to heat and is working really slow for my 30x40 shop. I am looking at going with a micro boiler but not sure what size is to big or to small.
@@cliftonneamon9001 Your shop is about as big as my house! Hopefully, it's well insulated. If you don't start with that any heating system will have to be oversized to get you comfortable. My best guess is just that your hot water tank is simply too low powered for the area you are trying to heat. First, do some calculations for how much you heat you will need. You'll need to know your shop size, insulation value, lowest winter temperature, temperature you want to heat to, etc. With that, you can figure out how many BTUs (or kilo-watts) you will need for heating. Here's a simple BTU calculator to get you started: www.calculator.net/btu-calculator.html I also highly recommend reading MODERN HYDRONIC HEATING by John Siegenthaler. It is a college textbook, so it can be a little expensive, but the information in there is fantastic. amzn.to/2xhaoO5 You might be able to get it through your public library system or even as a rental.
@@BenjaminNelsonX I live in Oklahoma so my winters are nothing like yours so i can see why you only take yours up to 50 from outdoor cold temps. Yeh it is big and its attached to another 30x40 lol. I appreciate your help! I'll go now and take a look at the calculator. Thank you again!
Hi Ben, great information. I’m currently installing a 4500 square foot driveway, we’re using concrete pavers on top of the system though. I had a question on those staples? Where did you purchase them?
I just got them from a big box home improvement store which carried a line of hydronic products. You could also order from a place like www.supplyhouse.com or www.pexsuperstore.com
I live in Arizona, so I’ve thought that it would be nice to “cool” my concrete slab in leu of conventional AC...then send the heat into a swimming pool. (Which, no matter what the temp is outside, you’d want close to body temp). So it seems would go hand-in-hand
Hi Ben, thanks for the info, how thick is your concrete slab? I'm planning on pouring 6" concrete but not sure if placing PEX on foam board at bottom will work ok. I know recommendation is to place PEX near middle of slab but easier to install PEX on foam board.
My concrete is 5 inches thick. I stapled the PEX right to the foam insulation. That's easy to do yourself. I've heard that the latest recommendation is to install it near the middle of the slab, but that gets a little trickier. Zip-tied to the reinforcing wire is probably the best way to go to get the PEX a little higher. If you have a thicker slap, you probably really DO want to make sure to get the PEX higher.
In this case, I was making a concrete foundation and slab for a new building anyways. Very easy to add tubing before pouring concrete. Not so easy to add after! It also IS possible to add a thin layer of concrete (or sometimes other materials) over the TOP of existing concrete. There's also some products that are like floor tiles with grooves in the underside so that PEX tubing can snap in place under them. You just lay those tiles down over the top of your existing slab/floor. There is more than one way to do hydronic heat, but if you are pouring concrete anyways, it's a good time to do it!
Links to the other two videos are in the description!
This is a three part video:
Part 1: ua-cam.com/video/y7SZPfXn2w8/v-deo.html
Part 2: ua-cam.com/video/Eawgtg4V7tA/v-deo.html
Part 3: ua-cam.com/video/qwoeAWtTvXI/v-deo.html
Wow Benjamin
I have placed pex tubing in my 3 car garage slab and just getting around to configuring the heating portion, hence the reason i found this video.
Additionally, i have a Mitsubishi I-miev and a off grid solar system..
Apparently we have a few common interests ;)
Rock-on
Thank you for this, I am building a 500sqft garage and the info in here is very helpful.
This is the best heating system
Very well done video. Thank you for taking the time o document your process!
Great job. One thing I think would've done to improve the system is to place the tubing on a floating shelf of metal reinforcing wire to sit in the middle of the concrete slab. That way the heat is distributed closer to the top of the slab where it's benefiting you the most. The boiler would also require a lower max temp to achieve the same result. All this goes out the window however if you were drilling in multiple spots of the concrete slab for shelves/car lifts, etc.
Thank-you for this great 3-part video. The insulation goes under all the concrete, both the slab and the foundation? How is the insulation on the side of foundation protected from the elements, or from getting chipped away? Thanks!
The insulation goes under the slab, and around the edges of the slab, with a thermal break between it and the foundation wall.
The exterior of the foundation wall is covered in foam. (I don't recall how thick. 3/4", I think.) The exterior foam is then covered with a metal mesh, and that was covered with a concrete in sort of a stucco finish.
Foam on the outside of a building definitely needs to be protected.
@@BenjaminNelsonX Okay, that all makes sense! Thank-you for answering :-)
wow this is really descriptive. thank you!
dude just 2 words thank you.
don't you need a feed water supply , threw a muler valve to keep your system full if there were any leaks ?
There are several different styles of systems. Some of them just use tap water and ARE designed with a connection to city water.
This is NOT like that. It's a sealed system using glycol. No water connection is needed.
Looking forward to part2. 26000 btu is quite a bit I can heat my garage with about 15000 which is a 4500 watt electric heater my garage is 28x30 which is fairly big. The heater can make it 80 degrees in winter and I am at 45 degree latitude is it does get cold.
26,000 BTU was a quick estimate of the heat required for a space this size. The actual heater itself produces a peak of around 24,000 BTU. That also doesn't mean that the heater actually outputs that much constantly. The heater throttles down it's power once the return water starts warming up. A big part of BTU ratings is about how FAST you can heat a place. Given enough time (and insulation) even a very small heater can heat a large space.
Frankly, this was the lowest power micro-boiler I could find! Once the space is warmed up, it doesn't take much heat to keep it warm, but it's a fairly significant amount of work to warm up the large concrete slab in the first place.
Do you find that the tiny hydro shark is sufficient for your space?
Would you have gone with something bigger if you did it over?
Seems to work fine.
Keep in mind that I'm not trying to heat to 70 degrees 24/7. Just bring it up to 50 or so in the winter.
I've really had no issues with this system. I typically just flip the heat on the night before I'm working in the garage.
Great video and wonderful details.
How would you compare the heating you used vs. a chiller heat pump with a variable compressor which runs on electricity for space heating, space cooling, and hot water. A few brands doing this are Multiaqua, Chiltrix, and Daikin. Sanden does a good job too; however, they only do space heating and hot water.
I couldn't tell you how it compares exactly, because I don't have a heat pump. And even if I did, I'd need to have it hooked up to this system to give a truly proper comparison. This is just a resistive heater. The best part of heat pumps is that they are several times more efficient than resistive electric heat. However, air-to-air heat pumps only work well down to a certain temperature and then often switch to a backup resistive heating element anyways.
My master plan is to use a wood-burning boiler or some other alternative heat source as part of this heating system.
BenjaminNelson thank your response.
I spent a little bit of time this morning trying to analyze this.
Your system is superior to all others due to heating up the large mass of the slab.
Cost wise I got different answers. For all I added up equipment cost, energy cost, maintenance cost, and hot water cost, and I ran these costs for at least 10-years.
The conventional AC is the most expensive. The next most expensive are heat pump chillers. Despite their higher efficiency when you have several rooms their cost adds up due to requiring several outside units as well as several inside units, and the outside units are expensive. For a single room like your garage connected to a radiant hydronic slab it could make sense depending on the COP, the input kWh, and the source of energy.
The cheapest for a multi room use are solar AC units which run directly off solar panels, have a COP above 3, and consume on average around 0.6 kWh.
A wood or pellet boiler could make sense.
If you don't want to fight the pex when unrolling than you just leave the whole roll wrapped in the plastic wrap. Remove the end from the center of the roll and pin it down with a heavy object, and then just unroll it where it's needed.
The professionals use an "un-roller". It's sort of a frame that holds the PEX and a bearing so that it freely unrolls when pulling on the material.
Hi Ben, thank you for very informative video. I have a question: Did you calculate the benefit of solar PV electric heating vs. solar thermal for your hydronic system? From efficiency view, it is better to go with the second. Thank you!
If a person were purely to look at heating from an efficiency point of view, YES, solar thermal is much more efficient than converting sunlight to electricity with PV and then using that to heat. However, I can make and use electricity year round (and use it for lighting, power, heat, whatever I want,) whereas solar thermal heating is only appropriate for part of the year. Beyond that, when I need heat the most, the sun is at the worst position for it. I would want very steeply angled solar collectors, which does NOT match the pitch of my roof. (The garage is the only practical location for solar in my yard.) Solar thermal collectors on the roof would take up space that could otherwise be used by my PV. Frankly, I LIKE how the PV looks on the roof, and it would NOT look as good if it had to miss a few PV panels to have solar thermal collectors there instead.
Since solar thermal would be best at a steep (even vertical) orientation for winter heating, I instead chose to make one of my garage doors directly into a solar collector. It still looks nice and is functional, and doesn't require any pumps or tanks or even air vents. See the video on the Passive Solar Garage door at: ua-cam.com/video/EcuRfnP6E7I/v-deo.html
Is the 7 kw boiler big enough for your garage or do you think you should have went bigger and how long did you say it takes to heat your garage?
The 7kW is fine. I was never trying to heat my garage to 70º 24/7. I just wanted to have it be warm enough in the winter to work in a sweatshirt or light jacket, instead of freezing in the driveway like I used to.
The concrete slab is a significant amount of mass. If I want to warm up the garage from unheated, I definitely turn on the heat the night before. The next morning, I can turn it off, and the heat will continue to raise through the day.
It works pretty well if I'm going to be working in my garage all weekend in the winter.
The other thing is just having the garage well insulated makes a HUGE difference! I'll just turn on the heat every once in a while and it stays above freezing pretty much all winter.
Even when there's pretty large temperature swings between day and night, the temperature stays really consistent in the garage. The combination of thermal mass and good insulation works great.
I also installed a glazed door I designed to let in the sunlight (and heat!) on sunny winter days.
ua-cam.com/video/EcuRfnP6E7I/v-deo.html
@@BenjaminNelsonX I designed my system kind of like yours (Thank you for the video), but i just got it going but i used a hot water tank to heat and is working really slow for my 30x40 shop. I am looking at going with a micro boiler but not sure what size is to big or to small.
@@cliftonneamon9001 Your shop is about as big as my house!
Hopefully, it's well insulated. If you don't start with that any heating system will have to be oversized to get you comfortable. My best guess is just that your hot water tank is simply too low powered for the area you are trying to heat.
First, do some calculations for how much you heat you will need. You'll need to know your shop size, insulation value, lowest winter temperature, temperature you want to heat to, etc. With that, you can figure out how many BTUs (or kilo-watts) you will need for heating.
Here's a simple BTU calculator to get you started: www.calculator.net/btu-calculator.html
I also highly recommend reading MODERN HYDRONIC HEATING by John Siegenthaler. It is a college textbook, so it can be a little expensive, but the information in there is fantastic.
amzn.to/2xhaoO5
You might be able to get it through your public library system or even as a rental.
@@BenjaminNelsonX I live in Oklahoma so my winters are nothing like yours so i can see why you only take yours up to 50 from outdoor cold temps. Yeh it is big and its attached to another 30x40 lol. I appreciate your help! I'll go now and take a look at the calculator. Thank you again!
One more thing. How many kw are you using a month?
Hi Ben, great information. I’m currently installing a 4500 square foot driveway, we’re using concrete pavers on top of the system though. I had a question on those staples? Where did you purchase them?
I just got them from a big box home improvement store which carried a line of hydronic products. You could also order from a place like www.supplyhouse.com or www.pexsuperstore.com
I live in Arizona, so I’ve thought that it would be nice to “cool” my concrete slab in leu of conventional AC...then send the heat into a swimming pool. (Which, no matter what the temp is outside, you’d want close to body temp). So it seems would go hand-in-hand
Then you might want to consider a water to water heat pump setup.
Hi Ben, thanks for the info, how thick is your concrete slab? I'm planning on pouring 6" concrete but not sure if placing PEX on foam board at bottom will work ok. I know recommendation is to place PEX near middle of slab but easier to install PEX on foam board.
My concrete is 5 inches thick. I stapled the PEX right to the foam insulation. That's easy to do yourself. I've heard that the latest recommendation is to install it near the middle of the slab, but that gets a little trickier. Zip-tied to the reinforcing wire is probably the best way to go to get the PEX a little higher.
If you have a thicker slap, you probably really DO want to make sure to get the PEX higher.
Professor / teacher edition text books are often much less expensive.
👍👍
Literally Actually basically basicly actually literally
I fucking hate youtubers' poor usage!
Literally actually literally basically I literally actually blah blah blah
step one: lay a concrete foundation. im out
In this case, I was making a concrete foundation and slab for a new building anyways. Very easy to add tubing before pouring concrete. Not so easy to add after!
It also IS possible to add a thin layer of concrete (or sometimes other materials) over the TOP of existing concrete. There's also some products that are like floor tiles with grooves in the underside so that PEX tubing can snap in place under them. You just lay those tiles down over the top of your existing slab/floor.
There is more than one way to do hydronic heat, but if you are pouring concrete anyways, it's a good time to do it!