Gas Furnace replacement? 15 years old
AnimaMundi
| Posted in Energy, Heating & Insulation on
I have a Lennox Pulse 21V Furnace (C26-51FC-10 which i had installed about 15 years ago. a few years ago i replaced the motor (in the depths of a cold spell).
this morning i noticed that the inside temp was 58 when the setting was for 68 degrees. i checked the thermostat and it was set correctly. it is fairly new, it was replaced a couple of years ago.
i was told some time ago that a furnace reaches its replacement point at about 15 years. is this correct? i have put in a call to the technician to come on Monday to check the unit.
if i am to replace this furnace, i would appreciate your recommendations.
Replies
15 years would be short for a decent quality gas furnace -- you should get 25 or so (with maybe a motor replacement or some such along the way). The Lennox Pulse, however, is somewhat antiquated technology, and, from bits and pieces I've heard, had a higher than normal failure rate.
There are many good high-efficiency "condensing" furnaces on the market. We have a Carrier, installed 8 year ago, and it's been good so far. (But our original Williams furnace lasted 29 yearrs and was still going (with some bearing replacements, new thermocouples, and probably some other things I don't remember), and we have a 37 year old electric water heater (which will be replaced after Christmas -- it's on pretty thin ice, I'm sure).)
Gas Furnace
the mechanic came and thought a "lose" wire was the problem. he could not find anything wrong. when he left the furnace was working and it worked for a whole week.
Last night at 9 pm it was set at 68 but inside was 66. it did not come on before 10 pm when it was set to a lower temperature.
this morning i heard it come on at around 5 am and when i looked at the thermostat it said 63 degrees. it ran all day until a few hours ago when it was 66 when it was set for 68..
while writing this i heard the furnace come on. the house is back at 68 degrees.
so something strange is going on intermitently.
You sure it's not a sticky thermostat?
Oh, and one thing to double-check is that there are no low spots in the exhaust pipe. It should slope either back towards the furnace or towards the outside so that any condensation in the pipe will drain out.
First condensing furnace I ever saw was in my MIL's house, and they installed it with a long exhaust pipe that was only supported at the ends. It sagged in the middle and collected condensation, and that would block airflow. This in turn would trip the fiurnace safety. Added a pipe strap to raise the middle and it worked great!