Outdoor Wood Furnace Info

All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: ambonci on August 30, 2015, 06:18:54 AM

Title: Need some help sizing a new circulator pump
Post by: ambonci on August 30, 2015, 06:18:54 AM
As for a lot of us we are gearing up for the upcoming winter.  I need another circulator too have around just in case.  right now I have a grundfos 15-58 running on high setting.  My OWB is about 50' from the heat exchanger in my garage.  Its piped with 1" pex to and from heat exchanger.  I have a 30 plate for my DHW and a 50 plate for heat.  My house is not that big 1600 square feet.  My plan was to use the 15-58 as a back up and get a 26-99.  One of my problems is that my house has trouble getting past 74 degrees when its cold out, I got to thinking if my pump outside isn't big enough to feed that big exchanger then I wont never get enough BTU to heat inside.  Is my thinking off?  So will the 26-99 do a better job feeding my exchanger?

Thanks
Adam
Title: Re: Need some help sizing a new circulator pump
Post by: RSI on August 30, 2015, 08:39:43 AM
Have you ever checked the return temperature to the OWB? If the pump is not moving enough water then it will be a lot colder that the supply. If it is almost as hot then a larger pump won't make much difference.