Return to the Renewable Energy Forum | Post a Follow-Up

Preheating using solar

Posted by boots_cary (My Page) on
Sun, Oct 30, 05 at 1:12

My home is just over 2000 sq ft and located in the southeast. I replaced the a/c 7 years ago with a 12 seer system.
All of my heat and hot water is created by a gas fired boiler mounted outside of my house. It is a rather small apparatus in size, about 3 feet tall and a 18 inches wide. The water it creates is held in a storage tank within my house which does not heat the water...only stores it. There is an air handler which has water coils and the air blows over these water coils giving me forced air heat.
I am looking to replace the current "boiler" for a Noritz, but want to add a way to utilize solar collectors on my roof or behind my home to pre-heat the water. The back of my home faces SSW and I am not in a HOA.
Most systems, it seems, are utilizing radiant heat using this method.
My system as originally designed, has been working great for 12 years. Unfortunately, the people who manufactured my boiler, or whatever you might call it, dont make it anymore.
Anyone have any ideas or links to share?

Follow-Up Postings:

RE: Preheating using solar


Sounds like you may be able to pre-heat your domestic hot water; but with the heat type you've got it may be difficult to supplement it.

Running heated water through a heat exchanger that has a high volume of air blowing over it to produce heat for the house; requires a pretty high water temperature . . if it's too low the air will barely feel warm. I'll bet the water coming OUT of the exchanger is still pretty hot . . . and likely above what you can reasonably generate from solar collection.

As far as domestic hot water; you can surely pre-heat that via solar . . incoming water is probably 55-65 degrees; and you can easily warm that signfigantly with solar. Solar heat collection has it's limits in terms of max temperature . . . the hotter you want it the less overall volume you can preheat. In other words; bringing incoming water up in temp to ~ 90 deg via solar is far easier / faster than bringing it up to 120 deg.

If you had radiant in-floor type heat; you could fairly easily pre-heat the return water, as this type of heat runs about 120 deg max . . . your hot air / heat exchanger type of heat uses a signfigantly higher temp . . so likely is not practical to try and pre-heat via solar as the temp is too high . . .


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Renewable Energy Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here