Hey Stevehull, that's pretty rare to have radiant heat floors + A/C isn't it?

I figured that anyone with A/C ductwork would pick cheaper FANG

I have hydronic floors and A/C too. I wanted the floors to be the heat source for efficiency, comfort and the ability to use solar heat stored geothermally. You can't cool building surfaces for AC this way because of the condensation. Vapor compression is the easiest efficient way to get cooling. Wanted air filtration too, so this means forced air. Since the heatpump version of my equipment is 20 SEER instead of 23 for the straight cool and I wanted the bulk of heat to come from the floors, I chose the cheaper straight cool version.

BBP,

Here in central Oklahoma we have about 3600 heating degree days and 1800 cooling degree days. Low low heat design temp is about 0 F and 100 is the high cool limit.

So we need both. Too humid to cool floors as condensation issues when dewpoint > air temp.

Pollen is also real high here (almost year round) so pleated high efficiency (98% arrestance at 10 microns) filters on a low CFM air handler do a great job on that.

Steve


Steve

HERE is a description of a lot of my system and house. The more detailed thread about annualized storage of heat for floors and DHW is HERE.

The updated controller improves SEER to 23, and I have decided to go with a 330gal IBC tote with 234 gallons of phase change material in it instead of the 2000 gallon tank I described to buffer the floor and DHW.

That bag filter is way oversized: 96sqft (16 24x36" surfaces) of filter area-no significant restriction there! It hangs down vertically so it works at ultra low flows. Any other orientation and it would just collapse on itself. It is MERV 14 as recommended for hospital general operating rooms as well as pollen, but I haven't changed it in 4 years because the MERV 4 prefilters catch the lion's share of contaminants. Having so much surface area plus longer life due to the prefilters allows ultra filtration without overwhelming the head capacity of the blower.

MMT,
On the tote tank, I recommend the HDPE food grade, tough stable stuff.
I'm interested on how the phase change works out, I hope great.

Yep, those are good for 230F instead of the usual LLDPE at 150F. Any pointers on how to tell one from the other on quick visual inspection?

They will be stamped Food Grade and/or PEH

Have U seen these threads?

http://ecorenovator.org/forum/solar-...affin-wax.html

http://ecorenovator.org/forum/geothe...hp-source.html

http://ecorenovator.org/forum/solar-...e-storage.html

When I build my next house, I will use active solar, I got the panels & BIG 1,000gal tank cheap off craigs list.

http://ecorenovator.org/forum/attach...1&d=1394904861




I got a new Vie$$man dual coil 79gal indirect DHW SS tank off Ebay, $1000

My small Burnham RV3 boiler / solar system will add heat to tank via the bottom coil.
If solar tank is hot enough it will provide heat to Vie$$man tank.

The 79gal water contained in the tank will provide DHW (with TMV tempering it down to 134*F) with recirculation to fixtures.

The top coil will provide low temperature ODR controlled heat to the pex in concrete floors, continuous circulation with 3-way zone valves.

An Erie Boiler Boss 3000 Outdoor Reset Controller (another Ebay steal $160) will control the speed of a Taco 007

ECM pump can't be used here as Erie BB3000 unit uses PWM to control the variable speed of standard PSC motor pumps:

Note:
permanent-split capacitor (or PSC) motor also known as a capacitor-run motor, Power Factor typically from around 0.85 or 0.90 at full load to as low as 0.12 at no-load

My DIY Hydraulic Seperator / Mixer

Goes between top coil in Vie$$man tank and pex heat distribution system.

Main body is 2.5" cast iron fittings.

I copied this design from Caleffi $$$, it has rolled up fine mesh SS screen inside to remove air in system, Watts air vent on top.

Bottom has a drain valve, junk in system naturally settles there as water velocity slows down inside body, it has a strong heat proof magnet contained in drain.

IMPORTANT: Any system that has any steel or cast iron components with ECM pumps, needs magnets to capture the generated Magnetite, which would build up on PM rotors.

Heat input on upper left & return on lower left, the Vie$$man top coil is connected here.

System heat output on upper right (to zones) & system return on lower right.

Heat input pump from Vie$$man tank is a Taco 007, which is speed controlled by Erie BB3000 with it's feedback temp. sensor on right (output) after Alpha



http://i1134.photobucket.com/albums/...k/IMG_0107.jpg

You can get some sensible cooling with radiant floor. You take the return water off a 3 row coil with a low approach temp, and run it to the radiant. If needed, you can still add a mixing valve to make sure the water stays over 55-60F, especially in kitchen and bathrooms. It will only be a fraction of your capacity, but it reduces drafts.

But then you can save but reducing air handler and ductwork size to a minimum, mainly just for fresh air and air movement. A high velocity system might work well for this.

Further, the best set-up for water to water geo, is ideally to have a single loop between hot water, chilled water and ground loop. Then you simply pump to each loop as needed. But I'm not aware of any residential companies that are doing this. The advantage is precise humidity control and if combined with a small fluid cooler and solar, you don't need nearly as much ground loop capacity.

New house build in Western Australia
 

Hello everyone!
What a thread this is: 57 pages, 580 posts....

I have been reading all day, followed countless links and learned a lot, thank you all!!!

My interest is in a new home I will be building in 4~5 months, hopefully the last home I have to build:

• The ground floor is 196mq - garage= 150mq and the first floor is 122mq.
• The floors will be solid concrete on sand and limestone ground.
• Walls and roofs will be properly insulated,
• Flat metal roofs.
• Here it never freezes, but we need to heat the house 3~4 months a year
• 8~9 months we open the windows and let the sea breeze in the afternoon and the land breeze at night, but some days it goes over 40c (100F), so cooling ability will help.

I am exploring the ideas of:

1. Geothermal floor heating using a heat pump with solar as well.
2. Perhaps cooling with cool air exchange??
3. I am thinking to place the slinkies below the house in trenches, before I build the concrete floor slab, is that a good idea?

Any help to get on the right track deeply appreciated!

Keep smiling
Stefano

Hi all,
Just wandering if I can use black poly irrigation pipes for in-the-slab floor heating for the above house?

I have just copied this to the "The Homemade Heat Pump Manifesto" thread as I think it is more appropriate.
See you there.

SPIV no you should not use that kind of pipe for that application. I forget what kind of pex you need to use but only pex should be used

Only use O2 barrier PEX if u have any iron or steel in contact with the heating water, it will keep rusting by pulling Oxygen in through any non-O2 barrier type of tubing, best type is pex-al-pex with an aluminum layer in the middle, next down in price is PEX-A still good, lowest in price & quality is PEX-B

If I may join in...

PEX is High Density PolyEthylene (which is heat weldable) that has been subjected to a process that causes some of the molecule chains to cross-link. The 'PE' is Polyethylene and the 'X' indicates cross-link. Cross-Linking makes is no longer weldable (I tried and failed). It also makes it much stronger. It was designed in Europe specifically for hydronic floors. It is cheap and it is the industry standard. Why risk any other kind of pipe when PEX is so strong and affordable??

Everything BBP said about Oxygen barrier is correct.

With the addition that if you design your system carefully to use no iron (bronze or stainless pumps for instance), you don't need to worry about oxygen barrier.

I don't agree with BBP regarding the hierarchy of quality of PEX, as he does. I think each type has its own advantages.

PEX-AL-PEX is definitely the best O2 barrier. It does have a larger bending radius however, and is more likely to kink if the bend is very tight. If you are after high-performance floors, you will want close spacing which usually require smaller radius bends. Beware PEX-AL-PEX.

PEX-B is good as an O2 barrier. It has a coating on the outside which is designed to prevent O2 from entering the system. The outside coating is a bit 'sticky'. In concrete, this is not a problem. But if you are going under floor or above floor, or in-wall, the sticky surface can 'grab' and 'let go' when hydronic temperatures change. Which will be noisy (ask me how I know this). PEX-A has a normal bending radius.

PEX-A is not coated on the outside, and it is rather slippery by comparison to PEX-B. This might make it cheaper, but that doesn't make it lower quality. If your system has no iron components, it works just fine. PEX-B has the smallest bending radius.

-AC

NOTE: edit per BBC

A/C sorry but u have the properties of PEX-A & PEX-B reversed.
I used both types recently on my Sons house.
PEX-B has the O2 barrier on the outside, which can be peeled off somewhat.
It is also more difficult to pull through holes in the wood framing.
I much prefer the more expensive PEX-A
I used Mr. Pex brand

Sons house, 8,888' altitude in Crested Butte Colorado, zone 6.
I used over 10,000' of 1/2" & over 1,000' of 3/4" between boiler room & 6x manifold sets.
Sorry to say, only concrete slab was in garage, 4" of XPS under. I think this is the cheapest & best way to heat.
Rest of house, demanded by Son, the pex has to transfer heat to air & then to finished surfaces. Less efficient & must use much hotter water, because of this I used a modern cast iron high temperature boiler, Burnham ESC6
The 1/2" pex (4" OC) is suspended about 1-2" below subfloors with R30 Rock wool a couple inches below pex.
I Installed a couple thousand feet of 1/2" pex in interior walls wherever possible.
House has WAY too many large windows.

heat loss program was performed by the architects office (RESCheck)
They came up with 110,000 BTU / hour at design temp of -20*F
So I chose the boiler slightly larger at 113,000 at this high altitude.
I expect the boiler to run non stop at design temp

Buffalobillpatrick

I don't want to cause you grief but I had done staple up on a bedroom and an ensuite bathroom over a garage. The garage was heated but only to about 10 Deg C. It was a 1/2 poly-b tube on a 6" centre to centre with R28 fibreglass insulation beneath. The house is extremely well insulated.

The room was uncomfortably cold here in our Canadian climate. The water circulated was 80 Deg. C. and offered up no appreciatable heat.

The rooms have been changed to above subfloor Uponor system.

The balance of the system is in slab and now with 40 Deg C. (Geo and solar heated) water which is absolute nirvana.

Just a word of caution. Again I don't wish any ill will.

If your going forward and the work is complete I pray to the in-floor heating gods your result will be markedly better!!

Randen

Good concern Randen
I probably have twice as much pex per square foot as what u used (6" OC)
The state of Colorado rural counties inspector (Andy Clark) inspected it before insulation & Sheetrock.
He was impressed & said that it was "over radiated & probably wouldn't need over 140*F water to heat it" I think 170*F AWT will probably be needed at design temp.

It is getting down in the teens at night there now & it's doing fine.

The system is of my own design that I call "Buffer Centric"

There is a large Rheem ST120 DHW / buffer tank, it serves both functions.
The temperature of the tank is controlled by an ODR Tekmar 256, it ranges from 140* +- 15* when its above 60* outside, up to 170* +- 15* when its -20* outside.

In between the boiler & the tank is a GEA Flat 30 plate 5" x 12" heat exchanger.

When the Tekmar 256 tells the boiler to fire, 2 pumps come on, one on each side of the heat exchanger. Heat moves from the boiler into the tank.

During this the System pump (Grundfos Alpha) can be on or off depending on if any Ecobee3 thermostat is calling for heat.

Buffer tank mode:
If the system calls for heat after after the tank is up to the required temperature
& the boiler is off, heat will be pulled out of the tank and flow in the opposite direction through the heat exchanger to the system.

I had a system like this in my house for the last 3 years & now one is in my Sons new house.

Buffalobillpatrick

I wish that it performs well. You have experience with your home this is good. My experience was much different. I hated ripping it out for a re-do. But the ultimate result is superlative.

In another thread there has been some conjecture that you wouldn't be able to discern a heated floor. To keep a room temp of 21 Deg.C. the floor will be warmer to give up its heat load to the cooler air above. Therefore the sensation of a warm tile against your foot as you roll out of bed on a blustery winter morning is what you will revel in.

Randen

BBP,

Egad, that's 10 tons of heating! In Crested Butte, I don't doubt you will probably need it in a couple of months. It would sure suck to be cold all winter way up there. Please let us know how the house does.

My last house that I just sold was insulated very well & had great Windows.
When it was 0*f outside the floors were only 75*f to maintain rooms at 70*f
So about 10btu/ft2
Never had the warm floor feeling, always had to wear warm house slippers.

In my Sons new house, I think the floors will need to be about 85*f when it's -20*f outside.
It's insulated well, but had lots of huge Windows

Any way to get Vlad's diagram?
 

This thread is great. I'm planning a similar system to Vlad. Unfortunately the images he posted in 2012 no longer show up. Is there a way that I can see this pumping and electrical diagram?

This is a really big problem.

A HUGE amount of posts and information have been volunteered on EcoRenovator, and they should all be accessible. But they are not. Some people post their images here on the ER site, and they seem to remain available. Other people post images on second-party sites, and the chances of long term availability go out the window.

jasonvan,

Can you post the link where Vlad's images should have been?

I might be able to retrieve them for you.

Some small amount of EcoRenovator is available on Internet Archive.

If that fails, I may be able to contact Vlad. Geo_EN_Gee & I drove up to Canada to see his setup. I may still have his phone number. Maybe Geo_NR_Gee has it.

We'll do what we can for you.

-AC_Hacker

Here are some pictures from that visit.

http://ecorenovator.org/forum/attach...1&d=1479695213

http://ecorenovator.org/forum/attach...1&d=1479695213

http://ecorenovator.org/forum/attach...1&d=1479695213

http://ecorenovator.org/forum/attach...1&d=1479695213

http://ecorenovator.org/forum/attach...1&d=1479695213

http://ecorenovator.org/forum/attach...1&d=1479695213

Our very own AC Hacker
http://ecorenovator.org/forum/attach...1&d=1479695895

Drilling rod
http://ecorenovator.org/forum/attach...1&d=1479695895

http://ecorenovator.org/forum/attach...1&d=1479695895

Vlad and his drill rig
http://ecorenovator.org/forum/attach...1&d=1479695895

http://ecorenovator.org/forum/attach...1&d=1479695895