Triangle tube prestige solo 399. Blower keeps going

barbiera

Hi all,

I have a TT solo prestige 399 that is 9 years old. I just replace the 5th blower in 9 years. Worked with TT certified and trained service techs and spoke with their technicians many times. They recommended maxing out post purge cycle. That was 2 blowers ago. Changed outside exhaust from concentric venting to two separate 4” feeds that are 5 foot apart.

Any help in figuring out how to correct blowers from going every year?

Thanks.

kcopp

Nat Gas or LP? Is it dialed in w/ the combustion? Overfired?
I agree on the post purge.
What is the operating temperature at?

barbiera

Natural gas. Temp for water is set to 168. Not overfired as per tech last visit

barbiera

To clarify. Post purge was maxed out already and still needed to replace 2 blowers since that adjustment

Daveinscranton

Sounds sounds like exhaust gas reversion.  My intake and exhaust are widely spaced, both vertically and horizontally.  You may be able to see it on a cold day from the vapor condensate from the exhaust flue to the intake.  399,000 btu is big.  Lots of exhaust combustion products to possibly make their way back to the intake.  Combustion analysis is mandatory too.

Best wishes 

barbiera

Thanks for the reply. Combustion analysis. High fan CO2 was 9.3% and on low fan 8.5%. Meter reading o2. 20.8%.
From my read those are within spec.

Thoughts on the issue?
Real head scratcher even for the techs at tt

Daveinscranton

I would think that Triangle Tube would be able to decipher the failure mode if you sent them a dead blower.  An autopsy sort of.

Couple thoughts. Excessive cycling, like a minute or two (longer is better).  Exhaust gas reversion would do it.  5’ of separation between intake and exhaust is not much.  Last thought of mine is just a bit of a hunch.  168 degrees is pretty hot.  Heat takes its toll on all things electrical or electronic.  Unless specifically designed or perhaps over designed for it.  

I use a mod con in a radiant floor application.  Everything stays pretty cold.  Less stress.  

Heater motors in 911 Porsches were notorious for going bad.  All of them cooked.  They sat on top of an air cooled engine.  Not exactly a heating forum thought but a parallel problem.

tim smith

Here’s what I’m betting on. Heat exchanger tubes are restricted causing excessive heat in combustion chamber and killing wheel or circuit board on blower. Pull top and try and get flat stick of silvfos brazing rod down each tube, on both sides of dimples on each tube. We service tons of these and this is pretty much across the boards a maintenance issue on all the fire tube heat exchanger boilers. Just speaking about the ft heat exchangers made for the resid light commercial boilers by the same mfr for most the major mfrs. Not a defect just something not put in the IOM manual. Good luck.
Tim