cool air

woodmills1 · October 20, 2016, 09:10:46 PM

tonight my furnace was blowing cool air into the house. The fire was going well, the circulator pump is running. The pipes at the heat exchanger were hot on the in side but cool on the out. I cracked the connection on the out and closed the valve and water was coming out, so I took the out connection off and the whole exchanger got hot. I reconnected and when I turned on the furnace fan the exchanger got cool again. So, bad circulater, clogged exchanger or clogged pex? Thanks in advance.

Bill Saf · October 20, 2016, 09:30:59 PM

is it a new unit or have you had for some time? if the pump is moving water I would say a air lock at your heat coil if it worked when you shut it down for summer and not now I would say air.

woodmills1 · October 20, 2016, 10:09:59 PM

13 years with this set up and was doing OK since middle September, just today cool air. got water through heat exchanger just no reference as to how much it should flow

Bill Saf · October 20, 2016, 10:28:32 PM

so its been running as of sep and ok and today no heat that takes air lock out of it Id say pump.
air lock is common and the first thing I look for.

woodmills1 · October 21, 2016, 09:12:39 PM

thanks for the input, it was the circulator. The plastic impellers had shredded, so that is why the motor could still turn, leading to my confusion. Taco 009 bought off the shelf from Webb plumbing supply. Problem solved by noon. That pump and motor turned for 13 years of 24 7. Is that like 25 billion revolutions? QC to engineering, we had faliure at 25 billion revolutions. :P

LAZERDAN · October 21, 2016, 09:52:53 PM

woodmill 1
Either you are a math wiz or a good guesser. 1,708.200.000 revolutions per year x 13 years. My calculator does not go that high, but i think your really close. Had the same thing happen to mine after 7 years. Lazerdan

woodmills1 · October 22, 2016, 07:32:32 AM

Ldan, I used scientific notation. I started college before electronic calculators were inexpensive enough for ordinary students. Used a slide rule till 1971. so, yours would be 1.7 x 10 to the ninth power multiplied by 1.3 x 10. 1.7 times 1.3 is 2.21 and ten times ten to the ninth is ten to the tenth giving 22 billion.