Outdoor Wood Furnace Info

All-Purpose OWF Discussions => Plumbing => Topic started by: ST98 on October 13, 2013, 05:49:17 PM

Title: Initial return temps.
Post by: ST98 on October 13, 2013, 05:49:17 PM: I've seen lots of posts about the importance of return temps being in the 20 degree or less range. I'm not sure if that means in the initial call for heat.

When I put a load on my furnace I watch the temps on the side of the furnace. With no load it goes out at 185 and comes back at 183. Wether it's the 50' run or the 175' both one way. When I put a load on my return drops to around 100 or so in a minute and then climbs back up to maybe 170 in a minute or so. Then stays within 20 degrees difference or less for the duration. It seems that initial slug of cool water cools her down. I put heat exchangers sizes in as recommended. Everything else cycles fine. These reading are coming off the valves I installed on the furnace for out and return. The water sensor on the furnace might go down from 185 to 184.

Is this ok?

Thanks
Title: Re: Initial return temps.
Post by: jerkash on October 13, 2013, 07:17:17 PM: Do your pumps run continuous?
Title: Re: Initial return temps.
Post by: ST98 on October 13, 2013, 07:24:21 PM: Yes. 50' run 26-99 set on medium or high.
Title: Re: Initial return temps.
Post by: Scott7m on October 13, 2013, 07:55:52 PM: Your fine, it would be bad though if your returns stayed crazy low, but if its an initial drop and then it climbs back I think you'd be fine
Title: Re: Initial return temps.
Post by: ST98 on October 14, 2013, 04:12:18 AM: Did I plumb my HE correctly. 4 standard 1 1/4 ports reduced to 1 inch.

Upper right comes in from OWB, supply

Lower right goes back to OWB, return

Upper left goes to heating units, supply

Lower right is the return from those units, return

Thanks
Title: Re: Initial return temps.
Post by: Scott7m on October 14, 2013, 07:22:32 AM: Quote from: ST98 on October 14, 2013, 04:12:18 AM
Did I plumb my HE correctly. 4 standard 1 1/4 ports reduced to 1 inch.

Upper right comes in from OWB, supply

Lower right goes back to OWB, return

Upper left goes to heating units, supply

Lower right is the return from those units, return

Thanks

Yea it sounds fine!
Title: Re: Initial return temps.
Post by: ST98 on October 14, 2013, 04:56:42 PM: Scott, are you saying the he sounds fine or the return temps?

Is this normal or did I do something wrong?

Thanks
Title: Re: Initial return temps.
Post by: Scott7m on October 14, 2013, 06:36:30 PM: Quote from: ST98 on October 14, 2013, 04:56:42 PM
Scott, are you saying the he sounds fine or the return temps?

Is this normal or did I do something wrong?

Thanks

Yes it's plumbed right. Not much difference there as long as sides are proper.

In regards to temp drop. If its only initially I wouldn't worry much
Title: Re: Initial return temps.
Post by: ST98 on October 15, 2013, 04:52:56 PM: Thanks. I'd like to get along time out of this boiler and wanted to start on the right foot.

Thanks again
Title: Re: Initial return temps.
Post by: chillyhiker on October 15, 2013, 07:39:56 PM: If your stove is set at say 180...do you really need a temp gauge on the outbound line?...I would think you could just put it on the return line.. or cant you trust the Ranco or other auquastat?....just thnkin.
Title: Re: Initial return temps.
Post by: slimjim on October 16, 2013, 04:57:45 AM: Temp guages can and should be placed on the lines as the boiler aquastat is typically mounted on the upper side of the boiler and may not be an accurate reading of the water temp coming out of the boiler in the rear.
Title: Re: Initial return temps.
Post by: ST98 on October 16, 2013, 10:06:21 AM: I put them on all lines at the furnace. Honeywell gauges were like 10 or 15 bucks a piece. The outgoing temps and incoming temps are pretty much the same but the boiler reads a lower temp.
Title: Re: Initial return temps.
Post by: ST98 on October 20, 2013, 04:39:40 AM: One more question about return temps. If I have a thermostatic valve that is set at 155 and the cold slug of water goes through does it activate and shut my supply water off? How would I ever get warm water through?

Thanks
Title: Re: Initial return temps.
Post by: slimjim on October 20, 2013, 05:19:08 AM: Your thermistic valve should be simply mixing hot water with the return water to bring up return temps, it should not stop flow to the building completly
Title: Re: Initial return temps.
Post by: ST98 on October 20, 2013, 02:03:11 PM: I wasn't sure how it worked and thought I may have been over thinking it a bit.

Thanks
Title: Re: Initial return temps.
Post by: CountryBoyJohn on October 21, 2013, 05:44:11 AM: Can you guys suggest a cheaper alternative to this?

http://www.pexsupply.com/Cash-Acme-24441-SharkBite-Temperature-Gauge-with-1-Tee-Lead-Free (http://www.pexsupply.com/Cash-Acme-24441-SharkBite-Temperature-Gauge-with-1-Tee-Lead-Free)

I can't find temp gauges like ST98 mentions.
Title: Re: Initial return temps.
Post by: ST98 on October 21, 2013, 07:11:51 AM: http://www.pexsupply.com/Honeywell-Sparco-GT162-1-2-NPT-Connection-Thermometers-w-2-1-2-Dial-Size (http://www.pexsupply.com/Honeywell-Sparco-GT162-1-2-NPT-Connection-Thermometers-w-2-1-2-Dial-Size)
Title: Re: Initial return temps.
Post by: CountryBoyJohn on October 21, 2013, 07:27:11 AM: Ok, thanks. I did find those, but is there a "TEE" with that thread on top and pex on the other ends? I'm not sure how to connect those 2 parts into my pex tubing.