Gas and Oil Home Heating Furnaces - Radiant Floor Heat

I installed wirsbo radiant floor tubing 4 loops (200' each) in our house last year and it has worked fine, except for when the weather gets really cold out.

I did not install the heat transfer plates due to problems with noise/expansion during a heat cycle.

I run the system off a Burnham boiler 180* water with a 3 way Honneywell mixing valve and have it set to mix down the floor temp to apx 135* supply temp for the floor.

The manufacturer has said that the plastic pipe will take up to 180* supply an I could just cut out the mixing valve.

Has anyone run 180* water through Wirsbo plastic pipe with success?


Any suggestions?

Thanks

I have used it in applications where we had to fish it in a wall to get from point A to point B and it is on hydronic baseboard loops. I have not had to go back so I assume it is working OK. It makes me slightly nervous but if the manufacturer says it's OK you can't get any better than that.

I don't think I'd pull out the mixer because 180 all the time might be a little warm. Tha floor temp could get too high when you didn't have much heatloss.

I am not a heating guy but, I've been doing a lot of research on radiant heat for new construction and you may want to be careful turning up the temperature. Although the PEX is rated for 180, everything I have read says that you should not allow the temperature of the floor to exceed 85 degrees. Allowing the floor to heat above 85 can cause damage to the floor coverings, including carpet, linoleum, and wood. Most companies recommend the water to be in the 130-140 range, to avoid this possible problem.

Jeff Gr:

I don't have much experience with radiant floor heat in a residential setting but I do know about running a floor too hot.

In our area wood/electric combination furnaces are common, I have one myself.

A common problem is damaged floor coverings in applications where the floor above the plenum is not well insulated.
A friend who is a floor covering dealer asks as a standard question if there will be a wood burning appliance below newly installed flooring.

My point is that there will be a limit as to what maximum temp you can run your floor at.

If your floor heat cannot maintain temp when run at 140 deg or lower there is a good chance you do not have enough surface area.
Perhaps the lack of the heat transfer plates has something to do with it as well.

Have you any other souces of heat or just the radiant.