Heatloss Calcs versus Reality

ken wickre_9

You may have one room that has been satisfied with the lowest water temp selected by the software. With only the one water temp utilized, the balance of the rooms will require supplemental heat. You can get around this by zoning with additional temps, closing up loop spacing, etc., to eliminate the "need" for supplemental heat. Talk to your Rehau representative and see if you can email your worksheet to him for his review and help. He can be an invaluable resource in learning to use their software. To those of us who desire (have?) to learn on our own, the learning curve can seem long and hard - but working through something like you are experiencing in this case can be some of best training you get.

Rob Blair

Heatloss Calcs versus Reality

I use Rehaus heatloss program. When I do the heatloss and come up with 15+ btus required it usuallyt will tell me that I require supplemental. It will only push the floor limit to about 76 or 77 degrees. If I do the math and stay at 85 or below I should be able to get 34 btus at 68 degrees.
Is my assumption wrong?
Thanks,

Rob

Mike2

Warmsource

Your problem is with the maximum material temperature setting. Finish floor materials such as hardwood have a MMT setting of 85deg F. This is for the underside of the finish floor. If you leave MMT at 85 your top side will only be about 75deg. Just be careful about what temp your finish floor can really take.