GeraldM
New Member
Hello there, this is my first post to this forum and am hoping for some common sense advice on what to use as a source for space heating and domestic hot water.
I live in Oregon in the Willamette Valley and have a 17 year old timber frame with in-floor radiant heat (tubes embedded in concrete) heating approximately 1600 sf. Per the original heat calculations performed by HeatLink in 2000, the total heat loss is ~22,000 Btu/hr. There are 3 showers, but never used simultaneously by us.
For the last 17 years, a low-efficiency Bradford-White water heater provided DHW and space heating via a separate coil. The radiant system has 6 zones of varying lengths, zone valve motors on each zone, a primary circulation pump and a secondary circulation pump that brings hot water from the tank to an injection valve (that only opens when the load side temperature drops below the prescribed supply temp as determined by the Tekmar 31320).
I now need to replace the water heater and am looking for an efficient option. I've considered the HTP Versa-Hydro (although finding someone in my area to install it isn't easy), a Navien NCB-240e, or possibly a separate tankless unit for DHW and a condensing water heater for the radiant side. I've read some of the other forums indicating the NCB-240e may be overkill for the radiant side, but not for the DHW. Irrespective of which option I choose, I'm confused how any of them will integrate with the existing electronics (or do I throw it all away), and how temperature is regulated on a tankless system if it's feeding directly into the heat side.
I apologize for so many questions at one time. I'm hoping someone can help me make some sense of this. HeatLink customer service tried but doesn't address the "input" side of the system, and the companies who have given me quotes aren't able to answer my questions about the existing system.
I live in Oregon in the Willamette Valley and have a 17 year old timber frame with in-floor radiant heat (tubes embedded in concrete) heating approximately 1600 sf. Per the original heat calculations performed by HeatLink in 2000, the total heat loss is ~22,000 Btu/hr. There are 3 showers, but never used simultaneously by us.
For the last 17 years, a low-efficiency Bradford-White water heater provided DHW and space heating via a separate coil. The radiant system has 6 zones of varying lengths, zone valve motors on each zone, a primary circulation pump and a secondary circulation pump that brings hot water from the tank to an injection valve (that only opens when the load side temperature drops below the prescribed supply temp as determined by the Tekmar 31320).
I now need to replace the water heater and am looking for an efficient option. I've considered the HTP Versa-Hydro (although finding someone in my area to install it isn't easy), a Navien NCB-240e, or possibly a separate tankless unit for DHW and a condensing water heater for the radiant side. I've read some of the other forums indicating the NCB-240e may be overkill for the radiant side, but not for the DHW. Irrespective of which option I choose, I'm confused how any of them will integrate with the existing electronics (or do I throw it all away), and how temperature is regulated on a tankless system if it's feeding directly into the heat side.
I apologize for so many questions at one time. I'm hoping someone can help me make some sense of this. HeatLink customer service tried but doesn't address the "input" side of the system, and the companies who have given me quotes aren't able to answer my questions about the existing system.