Outdoor Wood Furnace Info

All-Purpose OWF Discussions => Plumbing => Topic started by: rsv101 on August 06, 2018, 09:26:09 AM

Title: circulator pumps
Post by: rsv101 on August 06, 2018, 09:26:09 AM
any recommendations for circulator pumps for new install?
1. main circulator pump from wood boiler to 100 flat plate heat exchanger 160 ft from boiler to house 1 1/4 inch thermopex.
2. 4 circulator pumps for house, 1st for dhw for indirect storage tank, 2nd for main level baseboard hot water, 3rd basement in floor radiant, 4th garage in floor radiant.
3. second loop circulator from wood boiler to pole barn water to air heat exchanger.

what pumps and where does everyone buy them?

Thank you
Title: Re: circulator pumps
Post by: mlappin on August 06, 2018, 10:33:30 AM
For the house main loop I’d run a Grundfos 26-99FC on the first setting and check return temps, too large then bump it up to setting 2 then 3 if required. For the rest in the house a Grundfos 15-58FC on setting one should be plenty.

You don’t give a distance or line size from the stove to the shop.
Title: Re: circulator pumps
Post by: rsv101 on August 06, 2018, 11:09:19 AM
Thank you for the feedback, the loop from the boiler to pole barn is 30 ft one way
Title: Re: circulator pumps
Post by: mlappin on August 06, 2018, 11:29:51 AM
Thank you for the feedback, the loop from the boiler to pole barn is 30 ft one way

Probably a Grundfos 15-58FC will work fine there as well.
Title: Re: circulator pumps
Post by: RSI on August 06, 2018, 01:29:52 PM
Is the 1-1/4" Thermopex actually over 1-1/4" inside diameter? If so, you might be able to use 15-58 pumps for everything. It would depend on how many gallons per minutes you need.

If you want to use about half the amount of power, you could use ECM pumps instead of 15-58s. Grundfos Alpha pumps would have slightly less flow. Armstrong 20-20CI would be about the same or slightly more. There are also several other brands out there that are about the same size.
Title: Re: circulator pumps
Post by: E Yoder on August 06, 2018, 02:03:12 PM
I guess you could try a 15-58 or alpha on the main loop, if it struggles in cold weather get a 26-99 and keep the smaller for a spare (which I'm a firm believer in).
eBay usally has good deals on pumps.
Title: Re: circulator pumps
Post by: wreckit87 on August 06, 2018, 07:17:19 PM
1-1/4" Thermopex does measure a true 1-1/4" ID, which gives you only 6 feet of head in 320 feet round trip. Add in a couple feet for the exchanger and fittings, a 15-58 will still give you 10-11 GPM on high which is more than plenty for what you're trying to accomplish, speed 2 would give roughly 7.5 GPM which is also more than most of us get. As far as the radiant goes, anything under 15 loops of 1/2" PEX can also be served by a 15-58 if properly laid out in 300ft loops or less. Any idea how long your baseboard run is? Odds are that a 15-58 would easily do that as well if it's all 3/4" like they usually are. It may be worth going to an ECM circ like an Alpha to save some electricity, but the initial cost is 3x what a 15-58 costs on eBay. Realistically, if electrical usage is a concern, ECM circs and 24V zone valves offer a considerable power savings over the regular circs. I used to be a hardcore zone circ kinda guy and sometimes still am, but am coming around to the idea of using zone valves as they're not such a piece of crap as they used to be anymore. If power consumption is not an issue, I'd go ahead and buy a stack of 15-58FC pumps from eBay
Title: Re: circulator pumps
Post by: mlappin on August 06, 2018, 09:46:30 PM
1-1/4" Thermopex does measure a true 1-1/4" ID, which gives you only 6 feet of head in 320 feet round trip.

Good catch, I keep forgetting that Thermopex has a true 1 1/4” available.

A 15-58FC should work for all of them then.
Title: Re: circulator pumps
Post by: bill birks on August 23, 2018, 06:04:08 PM
 just a question on pumps \ getting ready to install 2 new grundos- reading inst it tells you to remove check valve -just wondering why the want them removed
Title: Re: circulator pumps
Post by: E Yoder on August 23, 2018, 08:20:22 PM
The check valve is only needed if you have it plumbed in such a way that it can develop backflow or forward "ghost flow". Otherwise the check valve reduces flow rate and is useless. I usually yank them.
Title: Re: circulator pumps
Post by: Scratch on August 24, 2018, 08:42:56 AM
Tag
Title: Re: circulator pumps
Post by: bill birks on August 24, 2018, 06:31:00 PM
 thanks again