Original message
| DAVESNYDER
 |  "LENNOX ROOFTOP ROTTING OUT"
, posted Tue 7 Sep 13:37:  
I AM LOOKING FOR ANYONE WHO HAS HAD A SIMILAR EXPERIENCE, WE ARE WORKING ON SOME LENNOX TEN TON ROOFTOP HEAT/COOL UNITS. THEY ALL HAVE SEVERE RUST PROBLEMS AND ARE RUSTING OUT INDUCERMOTORS LIKE THEY'RE GOING OUT OF STYLE. THE UNITS ARE ONLY 3.5 YEARS OLD. THE INTERIOR OF THE HEAT EXCHANGERS IS RUSTING OUT BAD!!
CUNNINGHAM AIR AND HEAT
[this message was edited by DAVESNYDER on Tue 7 Sep 13:39] |
| Replies:
|
| johntindale
| "Re(1):LENNOX ROOFTOP ROTTING OUT" , posted Tue 13 Sep 16:34
Perform a combustion test to make sure you're getting proper combustion when the unit is fired, and if your co and oxygen readings seem ok-your problem could be related to (believe it or not) low or high gas manifold pressure. hook up a gas pressure gauge and see if your gas pressure drops off at the gas valve when the burner kicks on.
i have also seen heat exchangers sweat in the winter when the indoor air is at 70 and the outdoor air is cold, and the unit is being used for makeup air, or if the indoor fan motor is switched in the on position. the cold moist air will actually condense in in the heat exchanger. Continuously running the inducer motor will alleviate this problem.
john tindale
|
| xenos
Webmaster 
| "Re(1):LENNOX ROOFTOP ROTTING OUT" , posted Mon 8 Nov 22:39
It sounds to me like the temperature rise may be too low. or the return air is too low. Make sure the temperature are up as it sounds like you may be condensing too early.
Xenos.
The best way to escape a problem is to solve it.
|
| printreader
| "Re(1):LENNOX ROOFTOP ROTTING OUT" , posted Tue 7 Sep 23:11
I have seen two instances with real bad rust (detioration) of the inducer fan and heat exchangers on recent lennox rtus. both are near our local conoco plant, and we have now proven the heat exchanger corrodes here as a result of the caustic chems at the plant. hope this helps.
i fix therefore i am.
|
| | Mastertech
| "Re(2):LENNOX ROOFTOP ROTTING OUT" , posted Tue 7 Sep 23:16
Stole my thunder LOL. I have a print shop that use amonia and it eats all the metals.
Not sure what u can do.
Oh that suff is nasty.
|
| Xenos
Webmaster
| "Re(1):LENNOX ROOFTOP ROTTING OUT" , posted Tue 7 Sep 20:17:
Sounds to me like your TD may be too low, I would be checking that first, next would be doing a combustion test for some reason your creating too much moisture.
Xenos.
The best way to escape a problem is to solve it.
[this message was edited by Xenos on Tue 7 Sep 20:18] |
| | james mo
| "Re(2):LENNOX ROOFTOP ROTTING OUT" , posted Mon 8 Nov 21:47
Oversized? Short cycles--Prevailing winds reducing combustion air blower output--Partially blocked exhaust--You could use the Carrier trick and run the combustion blower with the B terminal so it will run whenever stat is in the heating position
Another day in paradise
|
|
|
