Furnace Thermocouples

I have Carrier gas furnaces in the house, one upstairs, one downstairs. Home was built in 1990. They eat thermocouples, which are apparently the devices that keep the pilot light lit. Three have failed in the last few years and low and behold, the upstairs has failed again. By failure, I mean the pilot light won't stay lit. Any explanation or solution to the recurring problem? Looking at the part from previous replacements, looks like a do it yourself job to replace. I've done major automotive work so it doesn't seem too intimidating to me, just awkward to get to.
I've also had to replace the circuit boards a number of times over the years at $300+ per pop and other parts like ignitors and capacitors. Since when are furnaces as reliable as a 1987 Pontiac? Needless to say if I ever have to replace them they won't be Carriers.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If you have had three fail in a year, I would suggest that you hit a bad batch of thermocouples or they are not properly installed. I have seen circuit boards go out for a number of reasons, like power spikes or defects. I have been able to repair some.

--
Joseph Meehan

Dia \'s Muire duit
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yup, bad batch. I had the same thing happed to me with some Honeywell TC's, the repair guy finally gave up and sent their whole inventory back to Honeywell. Current one is 6 years old.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
smcjensen wrote:

    That is a lot of thermocouples to replace in a short time. They are easy to replace, just make sure you screw them in properly and set the pilot flame correctly. There is no need to have a large pilot light flame, just enough to touch the thermocouple so that it works. Perhaps the current flame is too high or the contact for the thermocouple in the valve is corroded?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I am just curious, with the effiency of todays systems why you would keep throwing your money at something that is 12 years old and has a standing pilot? No offense but that is just dumb.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Oct 31, 8:24 am, http://www.thehvacmedic.com/cgi-bin/forum/Blah.pl wrote:

Depending on the chimney condition, he may need a standing pilot.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Oct 31, 9:24 am, http://www.thehvacmedic.com/cgi-bin/forum/Blah.pl wrote:

No offense taken although replacing 12 year old furnaces sounds dumb to me. High efficiency furnaces are not cheap.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
smcjensen wrote:

Cheaper than you think.
--
Zyp



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.