Hello all. I'm going into the second winter in our home with a wood furnace and heat pump combo sharing the duct system. I spent my first winter coming to better understand our solid, but nearly antique King wood furnace from U.S. Stoves / Martin Industries. This time, I'm trying to ensure that the way the two furnaces are incorporated into the system is safe and up to modern standards.
As you might all imagine, the original owner/builder who passed many years ago, didn't leave behind any instructions for the house, so I'm left with making reasonable deductions as I go.
Here's my main question. I believe there is a reverse flow gravity style damper above the wood furnace helping to prevent air from the heat pump blower from continuing into the wood furnace. I can't visually see evidence of it, but I can hear slight metal squeak/swing sound when the wood furnace blower kicks on, and a very light thud when it turns back off. So, to me that's a strong audible indicator of a damper on that end. However, I have no indication whatsoever of a damper near the heat pump protecting it from the wood furnace.
I would add just two more pieces of information:
1. Just a few months after moving in last year, we had to have the whole heat pump system replaced due to the familiar story of a condenser going/gone bad and the repair bill would have been a significant percentage of getting a system with a warranty. So... I really want to ensure the existing duct set up is protecting my brand new investment. (And no, I didn't think to ask this damper question to the installers when the updated the system. I just wasn't far enough along in my learning curve at that point.)
2. The wood furnace is actual located quite a distance away from the heat pump, with approximately 20 feet of duct work in between the two. Which makes me wonder if the original owner/builder (who was himself a contractor for what it's worth) believed that distance between the two units allowed there not be a need for damper protecting the heat pump, believing possibly the heat from the wood furnace would perhaps be considerably less intense over that distance as to not endanger the heat pump. Of course, I don't know whether or not that theory holds any water at all. It's just something I thought of when trying to piece together why there seems to be a damper on the wood furnace side and not on the other – at least as far as I can tell.
As you might all imagine, the original owner/builder who passed many years ago, didn't leave behind any instructions for the house, so I'm left with making reasonable deductions as I go.
Here's my main question. I believe there is a reverse flow gravity style damper above the wood furnace helping to prevent air from the heat pump blower from continuing into the wood furnace. I can't visually see evidence of it, but I can hear slight metal squeak/swing sound when the wood furnace blower kicks on, and a very light thud when it turns back off. So, to me that's a strong audible indicator of a damper on that end. However, I have no indication whatsoever of a damper near the heat pump protecting it from the wood furnace.
I would add just two more pieces of information:
1. Just a few months after moving in last year, we had to have the whole heat pump system replaced due to the familiar story of a condenser going/gone bad and the repair bill would have been a significant percentage of getting a system with a warranty. So... I really want to ensure the existing duct set up is protecting my brand new investment. (And no, I didn't think to ask this damper question to the installers when the updated the system. I just wasn't far enough along in my learning curve at that point.)
2. The wood furnace is actual located quite a distance away from the heat pump, with approximately 20 feet of duct work in between the two. Which makes me wonder if the original owner/builder (who was himself a contractor for what it's worth) believed that distance between the two units allowed there not be a need for damper protecting the heat pump, believing possibly the heat from the wood furnace would perhaps be considerably less intense over that distance as to not endanger the heat pump. Of course, I don't know whether or not that theory holds any water at all. It's just something I thought of when trying to piece together why there seems to be a damper on the wood furnace side and not on the other – at least as far as I can tell.
