I'm trying to maximize the efficiency of our OWB, because we've got a very inefficient old farmhouse. It's our second winter in the house, and even after blowing insulation, replacing a couple windows, and chasing down every possible draft I could find, the OWB still can't quite keep up with all three zones. I guess it's a matter of principle at this point, but even though we're only going through about a therm and a half of gas a day (gas boiler is wired to kick on when the OWB starts to fall behind), I'm not going to quit 'til that gas meter stops moving.
Bottom line, I think I need about 10 more degrees of heat entering the house through the heat exchanger. With the OWB set at 180, at the top of the cycle when the blower shuts off the pex line in the house reads around 161. So I traced my heat loss backwards, and found most of it occurs right at the stove: the pipe leaving the back of the boiler reads 180, this pipe leads to a Taco pump and that reads 180 too, but then right as the pex leaves the pump, the pex reads 166 degrees. In the house this translates to about 160 or 161, so I'm only losing about 6 degrees between the stove and house - wish it was zero but I wasn't the one who installed the lines and I doubt they were insulated. So here's my question: why am I losing so much heat between the pump and the pex? Is that even possible, or is it a distortion of the infrared gun? I tried wrapping the pipe and pump with insulation, with no effect. Funny thing is, when I check the temp of the pex line re-entering the back of the furnace, the difference in the reading between the pex and pipe isn't nearly so extreme, which leads me to believe that the heat loss is real.
Here's a pic - red arrows indicate 180 degree reading, blue arrow = 166 max. The pic was taken pre-refab, I've since replaced these pumps and added insulation around the pipes and lines.View attachment 261493
Bottom line, I think I need about 10 more degrees of heat entering the house through the heat exchanger. With the OWB set at 180, at the top of the cycle when the blower shuts off the pex line in the house reads around 161. So I traced my heat loss backwards, and found most of it occurs right at the stove: the pipe leaving the back of the boiler reads 180, this pipe leads to a Taco pump and that reads 180 too, but then right as the pex leaves the pump, the pex reads 166 degrees. In the house this translates to about 160 or 161, so I'm only losing about 6 degrees between the stove and house - wish it was zero but I wasn't the one who installed the lines and I doubt they were insulated. So here's my question: why am I losing so much heat between the pump and the pex? Is that even possible, or is it a distortion of the infrared gun? I tried wrapping the pipe and pump with insulation, with no effect. Funny thing is, when I check the temp of the pex line re-entering the back of the furnace, the difference in the reading between the pex and pipe isn't nearly so extreme, which leads me to believe that the heat loss is real.
Here's a pic - red arrows indicate 180 degree reading, blue arrow = 166 max. The pic was taken pre-refab, I've since replaced these pumps and added insulation around the pipes and lines.View attachment 261493