February 1 , 2004
Two Weeks Ago...
Me and my big mouth. A few weeks ago winter hadn't arrived yet and I opened my big mouth about it and now we're paying the price. Not only has it been snowing (with a foot or more on its way), but it's been quite cold. The coldest weather in these parts since 1996 to be exact.
The fresh snow cover along with an arctic high pressure system sent the thermometer plunging to -17°F for two nights in a row. My plans were to stay in Illinois this last week to keep Jo company and work on the web site, but when I saw the temperature in the house down into the 50's with a forecasted low of -20°F, I decided to head on up to the house to make sure everything was okay.
And okay it wasn't! Upon arriving I discovered that the tankless water heater had froze up even with the indoor temperature in the 50's. The problem has to do with the lack of a damper for the powered-vent attachment on the Aquastar water heater. It never occurred to me that this would be a problem, but with temperatures well below zero, the cold air was pouring in right over the heater coils. Luckily, the pipes did not burst and within 10 minutes of heating up the coils, it thawed out enough that water began to flow. A short term fix consists of a ball of fiberglass insulation that has been strategically placed in the vent stack. I'll have to look for a damper.
I spent the remainder of Thursday night feeding a fire and getting the walls in the house warmed to room temperature. This has been a terrible winter when it comes to meaningful sunshine. Maybe I'm just not used to a real winter, but up until this one, the sun commonly would shine for at least two to three days in a row. This winter I am lucky if the sun shines brightly for one day in a row.
(Out of curiosity, I checked the weather statistics for January 2004 and January 2003 and found that January of 2003 had 15 clear days while this year there were only 9. It has certainly has made a difference in this year's heating bill. )
This has led me to rethink the heating system. If I was at the house 7 x 24 x 365, I would just shrug this off and use the wood stove. But since I am not at the house full-time yet, the electric backup heating system has been called for more often than I would like to admit. Last winter I used very little electric heat. The sun did a great job keeping the place relatively warm, but this winter things are different.
Friday morning I woke up to -17°F (unofficial), but the sky was nice and clear. (The day before, it was cloudy most of the day and it never got above zero.) I patiently waited for the sun to rise above the bluffs and at 10 a.m. the pumps began to run. I went to see what kind of solar heat was coming in through the pipes and the temperature did not budge. This was not good! With the panels sitting in the cold for three days without the sun coupled with the extremely cold air temperatures turned the anti-freeze mixture to slush. The pumps don't like slush at all and refused to do their thing.
I tried warming the pumps and fittings, but no matter what I did there was no flow. Panic began to set in. My concerns were for a pipe burst if temperatures and pressures continued to rise out at the collectors.
About one hour later, the pumps changed their pitch and fluid began to flow. I watched the incoming fluid temperature. Within a matter of seconds it dropped down into the 40's and then shot up to 130°F as the hot fluid that was sitting in the collectors made it into the house. I'm sure this stressed the system, but within 10 minutes things were running normally.
I called up Steve Krug to get his advice on what had happened. Steve didn't seem too concerned as long as the temperatures at the collectors didn't get up close to 200°F. I probably could add a bit more (non-toxic) glycol to the system, but you can't go over 60% glycol due to the viscosity of the glycol. The glycol is just too slick for the pumps to do their thing. The system is using a 50-50 solution at it's good to about -20°F. At that point, it starts to slush up. The fluid won't freeze unless it gets down to -50°F, and I hope we never see that temperature.
So for now, I guess I won't mess with it and hope that we don't see too many more days with temperatures around -20°F. Of course, we still have February and part of March to worry about. Keep your fingers crossed!
That's about it for now. There's 12" or snow on the way, but at least the temperatures are 20°F ABOVE zero instead of below. I had planned to discuss various options regarding the solar electric system and I hope to write about that in a few days. Stay tuned...
|Here's a photograph of a slightly frozen Aquastar with a frosty power-vent.|