Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Circulator pump moving water slowly on hydronic radiant floor system
I installed a hydronic radiant heating system into my home last spring. I am using a takagi-jr tankless water heater in a closed loop system. I am having a problem with the water not flowing quickly enough through the system. I have blead the lines multiple times and i have an air eliminator installed. I have an expansion tank set at the correct pressure (12psi) and I have an auto fill valve for the system set at 12psi. I have a bell and gossett circulator pump (i sized it up to this from a taco, but with no significant change) installed after the expansion tank and before the 7 loop manifold. Each loop consists of approx. 250' - 300' of 1/2" pex tubing. If i open the bleed valve on the return manifold i see an instant increase in the gpm of the pump. Once i close it, it slows way down. I have adjusted the valves to turn varying loops on or off with no signifcant change in performance. This problem is causing the heat to be distributed to my house very slowly. The pump seems to be functioning, the system is working, just moving water too slowly, the expansion tank seems to be set correctly and the water heater is operating properly. Anyone have any ideas? I have attached a picture to show the system.
This discussion has been closed.
- 115.9K All Categories
- 82.2K THE MAIN WALL
- 2.6K A-C, Heat Pumps & Refrigeration
- 40 Biomass
- 399 Carbon Monoxide Awareness
- 1.5K Domestic Hot Water
- 4.1K Gas Heating
- 102 Geothermal
- 146 Indoor-Air Quality
- 2.6K Oil Heating
- 40 Pipe Deterioration
- 646 Plumbing
- 4.7K Radiant Heating
- 345 Solar
- 12.9K Strictly Steam
- 2.8K Thermostats and Controls
- 46 Water Quality
- 573 Buy, Sell, Barter
- 30 Industry Classes
- 62 Job Opportunities
- 11 Recall Announcements