two zones, one boiler.

cracklin

Where can I get a functional diagram for hooking up radiant heating to an existing Slant Finn boiler(similar to what "drh" posted back in 07).
Right now the boiler heats the first and second floor.
When resurfacing my basement floor, I laid Pex tubing inbedded in the concrete slab intending to hook it up eventually.
Or do I have to bite the bullet and pay someone a doctor's salary???
Cracklin.

beenthere

Depends how good you are at piping and control wiring.

beenthere

Post pics of your current boiler and its piping.

cracklin

This is a test to see if this photo will be sent

cracklin

I guess it didn't work.
Will try tomorrow.

cracklin

[IMG]file:///C:/DOCUME%7E1/USR/LOCALS%7E1/Temp/moz-screenshot.jpg[/IMG]http://i884.photobucket.com/albums/ac47/cracklin/hvac/DSCN0646.jpg

http://i884.photobucket.com/albums/a...c/DSCN0636.jpg

http://i884.photobucket.com/albums/a...c/DSCN0646.jpg

Hi Beenthere.
Thanks for your interest.
The first image is realy a very short video. So it may take a while to download.
I have plumbed my whole house(all 950sq.ft).
I have also rewired my house as well as put in a new panel.....all to code.
I also have a "pex" crimper(1/2").
However, I am very humbled by the mechanical part of the boiler.
With all due respect to the trade, I'm simply amazed that they charge close to $2500 for one days work.

beenthere

Video link is not working. You have to upload it to a host site, and then link to it.

Was it 2500 labor.
Or was it 2500 including the parts and materials you don't have.

PS: Your back flow preventer is suppose to have a down pipe on it. Ran to within 6" of the floor.

Takes a little tie in work to your system, plus a mixing valve, and a circ.

Do you already know what temp your floor needs to be at. Along with your loop temp?

cracklin

http://s884.photobucket.com/albums/a...t=DSCN0643.flv

Hope this works.
The labour is $1500approx.
With parts $2000approx.
I know for a fact that they mark up the materials by
100% and up!!!. That adds up to $2500 for a days work.
I'm not sure but I think that pipe does go down to just above the floor.
I'm not sure about the temperature for the floor.
I do know that I need a mixing vavle to bring the heat down so I can walk on the floor. I also know that because the pex only holds 2 or 3 buckets of water so I need something to prevent the boiler from switching on and off at a constant rate.

beenthere

The back flow preventer is the brass device before the pressure reducing valve that controls how much water goes into your boiler. It doesn't have a down pipe.

Yep. Most places will mark up like that. Means they make 25% on the parts then(trust me, thats all it is).

I had a computer crash a couple days ago. I lost a lot of things. And most of my drawing programs were lost.

But, here is a copy of a drawing I made a couple days before crash that may or may not help you.

Attached Files

Quick Boiler High and Low temp Zones.pdf (5.0 KB, 155 views)

tk03

If it is connected to a cast iron boiler i would return bact to the return side of the boiler and not use a boiler demand. There will be plenty of hot water in the boiler between cycles to heta a basement floor. You will only need 80º - 90º degrees for the basement floor. Utilize the advantages of using the cast iron boiler mass and stored energy.

beenthere

In that PDF. The water is returned to the boilers return side. By the boilers circ.

tk03

Yes I see that as long as the boiler pump is running. I was saying not to use a demand from the radiant to the boiler and use residual heat only. With this being a basement heat zone the heat loss is very small. I would not want to run the boiler on such a small zone below grade. There will be plenty of calls from the other stats in the home. This is how I did my kitchen and lived there for 7 years after doing it and never was cold and did not feel temperature swings due to thermal mass.

beenthere

That diagram is from a mod/con boiler. that only holds 2 gallons of water. So it has to run the boiler.

Didn't know if you took notice to the full pipe configuration.

Do you get any forced flow through your radiant loop piping with it that way. Since you have more then 12" between tee's. You have a pressure difference between your supply and return for your radiant loop. When the other zone/zones are calling.
I doubt that it would effect heating any. As the flow should be too minimal to have any real effect on the radiant loops zone temp.

Cecosugi

We've got 5 zones. We're heating about 5000 sq ft off a boiler. We've got one zone in the basement floor. 3 zones on the main floor. 1 zone in the upstairs. We split a thermostat for 2 of the zones on the main floor.

Here's one zone http://picasaweb.google.com/lh/photo...eat=directlink

And here's all the zones, together http://picasaweb.google.com/lh/photo...eat=directlink

I will try to find the diagram we used. I thought it was here http://www.centralboiler.com/brochure.html, but that doesn't show the multi zones how we did them. I have it at home, so I'll scan it and send it if you'd like.

Basically, we had the hot coming in and dropping into each zone. When it drops in, there's a mixing valve (right side coming from hot, left side from the return lines), shutoff valve, taco pump, shutoff valve, backflow check, temp gauge, into the manifold, drain valve on the end. The return comes back into the manifold (with a drain valve on one end), then Ts up to a return pipe to the boiler and down through a temp gauge and back into the mixing valve.