boiler installation for radiant heat in slab

margo

I have a teledyne laars boiler minitherm JVT100000 that I want to use for our in slab heat for a pole barn. The boiler manufacturer suggested I post here for more specific help with the installation. Our heating/plumber has installed boilers, but never with in slab wirsbo tubing. Our 1/2" wirsbo hepex is already in. We have 8 -250' runs with 2 separate manifolds with 4 supply/return per manifold. Our contractor wants to use 1 1/4" copper to supply, wants the water to be at 180 degrees, has said nothing about a mixing valve. We are concerned about condensation and the pipe sizing. Is there someone or a website that could help diagram the proper installation of this boiler for this system? I can provide specifics as to the building size and insulation values and doors and windows. He says that this boiler can and should be changed to an electonic ignition? Is that possible?
thanks in advance for any help

Couderay

180 degree water

180 degree water is way to hot for this type of system, 130 is norm for radiant heat in the floor. I would probably go with a primary/seconday type piping arrangement. More information is needed,are you going to zone the system??

Unknown

Joe`s right...............

180* water?, that`s super-high for a slab, I would get a proper design, from the proper person, before applying that temperature!

ALH_4

low temp

It's always best to follow the manufacturer's instructions.

Laars has a diagram of what you need top left on page 13 of the JV Installation Manual.

Hope this helps,

-Andrew

Cosmo_3

Radiant

Just to add to Joe's good advice,

Who purchased the Wirsbo tubing?

Your plumber can contact Wirsbo's local rep in your area for help in selecting temperatures, pump, and pipe sizing. I agree 180 is too warm for concrete slabs. Generally the max temp you should be sending is about 130 F, of course you may need a lot less! And as Joe mentioned, the boiler needs to be protected from cold return temperatures by using a primary/secondary piping setup. The preferable set-up would be to use a control like the Wirsbo Promix 101 or 201 (or similar control from another brand) that can control water temperature out to the slab and also protect the boiler from low return temperatures.


Cosmo

Weezbo

nah..... nope....uh uh...

youd get more mileage out of a 4 way 1/14" Taco with out door reset. trust me....

Gronski Plumbing and Heating

Mixing water temp

140 is the maximum water temperature allowed by the concrete institute for heating it with radiant heating. I have slab on grades in buildings and homes that have never exceed 101 degrees to heat the building to 68 on a 0 degree day. I also have snow melt jobs that run 117 degrees to keep the driveways 37 degrees on zero day melting snow. You have many mixing options available to you. I would be willing to bet that your feed and returns to the manifolds would not require more that 3/4" in size.I use quite a bit of 5/8 Wirsbo to supply my manifolds on jobs and they do just fine with the right circulator, and 90% of the time a 007 does the trick. If your looking for an inexpensive way to do it and still do the job,a 1" Taco I series mixing valve with what ever size circulator you need to over come the head would do the trick. If you have the dimensions of the slab, exterior Wall lenghts and height ,ceiling height, windows and door sizes in each wall insulation r values in walls and ceilings, I have the wirsbo ads program and can probably tell you what your temperature and head loss would be an as well as your supply and return size. you can email me at contact@gronskiplumbingandheating.com with the info if you care to.
Steve

Cosmo_3

more than one way

To skin the same cat!

Four way valves are great, and most applicable with boilers that need protection. But you can also use three way, injection, or manual valve. Gpm of secondary loop is a factor to determine method as well as $.

First determine your budget and try to get the most bang for your buck......


Cosmo

Paul Rohrs_4

You might consider

a Wirsbo (now Uponor) propanel. If you are concerned about the skill level of your installing contractor. The Propanel 201 would be a good recommendation, especially if the heat-loss of your building states that the boiler is adequately sized. This injection mixing panel would protect the boiler with minimum inlet temps, and would give the correct reset temp to the floor as needed.

Regards,

PR

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Paul Rohrs_4

You might consider

a Wirsbo (now Uponor) propanel. If you are concerned about the skill level of your installing contractor. The Propanel 201 would be a good recommendation, especially if the heat-loss of your building states that the boiler is adequately sized. This injection mixing panel would protect the boiler with minimum inlet temps, and would give the correct reset temp to the floor as needed.

This is a small pre-piped box with controls that the installing contractor can just run his pipes to and then it is just a matter of programming.

Regards,

PR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

margo

wirsbo

We purchased the wirsbo tubing from a local supply house. Did the install ourselves. We just knew that someday we would want the heat installed and before the concrete went down, the insulation went down and the wirsbo went in.
thanks for the replies

margo

instruction manual

I have a copy of the instruction manual, but is must be an older version, I don't have all those pages. I printed a new copy. I did show the manual to our contractor and his reply was "you read it, I don't need it" not the right answer!!!

margo

boiler help

We read alot about radiant in slab heat, but it's not easy telling your heating/plumber that he is wrong. And we have never done this before(apparently neither has he). so we only knew what we had read. There are alot of installers in this small town that claim to know radiant heat, but we disagree. Our boiler is JVT 100,000. One contractor wanted to use a 40,000btu tank heater. I didn't like that approach. We believe we need the boiler with a closed system and a glycol mix. Now we need someone that knows how to install it correctly. We are in NE Ohio and it does get cold here.

margo

zone

We had originally planned on having 2 zones, one for working, and one for cold storage. Right now, it is just one big expanse of a building, no interior separations. We did install a small office and bath. There is one manifold that has 4 lines in the front half of the building and the other manifold has 4 lines for the back half. They each have 3/4" copper tubing connected to run to the boiler. But our plumber says that is wrong and it should have been 1 1/4". He was ready to tear it all out, and we stopped him. Decided to ask for information first and maybe get a different contractor.

ALH_4

warning

You have the wrong contractor. This is standard stuff. Even if he knows what he's doing, his unwillingness to explain it to you and compare it to what the manufacturer recommends is a huge warning sign.

-Andrew

Weezbo

zone valves make life better .

Taco also makes 3/4",1"/two way I series with out door reset.

and an I series setpoint for boiler protection.....

depending on your piping stradgey ...

i checked page 13 of the manual and didnt see a word one about a four way mixer ...evidently i dont know What i am talking about *~/:)

margo

great help

Your answers and help have been great! We have stopped the project until we can find a contractor that will install it correctly. Or at least be willing to listen to all your advice. It's starting to snow in Ohio. But until the design is right, we will wait.