AboutMorgan M. Audetat Expertise Radiant floor heating. Snow Melting. Boilers. Indirect water heaters. Tankless water heaters. Current owner BadgerBoilerService.com Minneapolis based mechanical contractor specializing in Mod/Con based, integrated heating systems. System design, consulting and technical training world-wide.
Currently designing hot water based heating and snowmelting systems for spaces ranging from 50 to 50m square feet. Consulting fees start at $500.00US
Experience 30 years. Organizations: Charter Board Member - Radiant Panel Association, former manufacturer of the first American-made wall-hung, sealed combustion condensing boilers, son and apprentice of mechanical & plumbing contractor.
Continuing Education: Uponor/Wirsbo advanced design school 2007, Power Limited License (low voltage controls) 40 CE credits 2005, B&G Little Red School House 1993, Tekmar Controls residential and commercial 1993, Division Manager and Advanced Hydronic Seminar Host for the first Hydronic Radiant Floor Distributor in the USA 1990, Hydronic Heating Association Workshop participant with Richard c. Bourne, PE spring 1988, Master Plumbing/Hydronic/Solar Course Red Rocks Community College 1987.
Education: B.S. University WI 1981, 26 yrs. continuing education.
Licensed CO, MN & WI. Home Inspection license WI exp.
Awards and Honors: My momma's favorite son.
Past/Present Clients: References upon request.
Expert: Morgan M. Audetat Date: 5/27/2008 Subject: Incorrect sized pex piping
Question 8 years ago, radiant heating system installed in our home. We heat 95% with wood. Last couple of years, we've been 'lazy' and used the radiant system. Boiler couldn't keep house warm when it was -18C outside. Reviewed everything with other heating contractors and discovered that the original heating contractor installed 5/8" pex pipe instead of 3/4" pex pipe as was specified by Wirsbo in their engineering drawings. This is a significant reduction in cross-sectional area of pipe. Slab on grade is 8" thick with 2" styrofoam under and around perimeter.
We have other problems with the oil boiler and are about to change it to a LPG boiler.
New heating contractor indicates that increasing the temperature that flows to the floors will solve the problem. We're going to install a Trinity Ti200C unit and it will supply instantaneous DHW. Old system had a heat exchanger tank, but the control board is burned out in it and it no longer works.
I was wondering if a circulating pump that could move the glycol through the pipes at a faster rate might help or if there were other solutions that might help get the house to stay warm when using the radiant heating?
Also, The Ti200C is capable of producing 5.5GPM of DWH at 110 degrees F. Our shower heads flow at 5 GPM (tested with a 5 gal pail and a stop watch). Any thoughts on this type of DHW production over storage/heat exchanger tanks?
Thanks
Tony Ferguson
Answer Glycol bad, water good. A system with glycol produces less heat and costs more to operate. I only use it in unoccupied structures and for snow melting.
I never use 5/8" tube, as it is a silly contrivance in all but the most critical applications. 1/2" and 3/4" will do a great job in 95% of all radiant jobs. 3/4" PEX is rarely used in residential applications save snow melting.
The Trinity is a fine unit but I would install an indirect fired water heat (please read previous posts).
Your contractor is probably right as the space between tubes, water temperature, and water volume all play a role in panel output.
