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NTI ER6 code in cold weather

panmanpanman Member Posts: 82
I put this problem out there last year and thought i had it fixed. I was wrong, or should i say my gas company was wrong. I keep getting an error code ER6 on my trinity 150 propane boiler when temps drop down around 0. If u by pass my exhaust senser, it will run with no problem. My circulator is on high moving water through the boiler as fast as possible, the boiler is super clean, exhaust test were exellent, gas pressure is 11 lbs. my boiler high is set at 180. After error code, you can turn power off then on and it will run for 1 cycle then i get error code ER6.

Any info will help thanks. Panman


  • Terry OTerry O Member Posts: 60
    Maybe this will help... fyi.... for your tech:


    “Flame Lock Out”

    Sentry has sensed a lack of 24V to the gas valve during operation or a

    Fenwal ignition lockout. There is a problem in the ignition sequence, it could be caused by a faulty igniter, flame sensor, gas valve or improper line pressure or combustion. Check ignition sequence to determine which component is not functioning. (Sentry will retry ignition sequence 1 hour after ER6 code originally occurs or if control is reset)

    If a 3-Flash error occurs on the Fenwal controller prior to locking out on an Er6,

    proceed to “Three Flashes on Fenwal”.

    Three Flashes on Fenwal “Ignition Lockout”

    Check the condensate drain for blockage – a blocked condensate drain will flood the

    combustion chamber and cause this error, see Section 5.0 for further instructions.

    Reset and observe ignition sequence:

    1. If the burner ignites then goes out within 2-3 seconds:

    a. If the boiler is newly installed, check the polarity of the 120VAC power

    supply – reversed polarity will cause this error.

    b. Ensure the cable is connected to the flame sensor.

    c. Check for proper sustained gas line pressure.

    d. Check venting and combustion chamber for blockage – clean combustion


    e. Replace flame probe.

    f. Replace Fenwal controller.

    2. If the igniter glows but the burner does not ignite:

    a. Check for proper sustained gas line pressure.

    b. Check venting and combustion chamber for blockage – clean combustion


    c. Replace igniter.

    d. Replace Fenwal controller.

    3. If the igniter does not glow:

    a. Replace igniter.

    b. Replace Fenwal controller.
    Terry O
  • panmanpanman Member Posts: 82
    re ER6 code

    Thanks for the info Terry O. All the info you listed has been checked. Fire is clean, gas pressure 11lbs, condensating drain is working fine. Last night it was 10 degrees ABOVE 0 and it ran flawlessly all night. Night before it was -12 and it error coded ER6 in the middle of the night. I can turn power to the furnace off then on and it will run and heat the water to temp for 1 cycle then flash aquick ASO then seconds later ER6. The cold temp is somehow triggering the stack sensor. So far techs and 1 trinity installer cannot pin point it. after 2 years of this and $1500 later i am a little frusterated. Thanks- Peter
  • panmanpanman Member Posts: 82
    NTI ER6 code in cold weather

    Are there any gas tech's that have an idea or experienced sub zero weather effecting the stack sensor. I can't be the only one that has an NTI with this problem. Furnace runs flawlessly until - weather. After sitting an hour the furnace cycles once then kicks code, so it has nothing to do with boiler being too hot and triggering the stack sensor. The cold air is messing with air flow or something. Has not ER6 coded for days since the temp went above 0. Thanks
  • TomTom Member Posts: 458


    I know you have already talked to NTI but there support is a member here on the wall. NyTechSupport is the name I believe if they are still on here. You could try contacting him.
    Montpelier Vt
  • panmanpanman Member Posts: 82

    Thanks Tom
  • kcoppkcopp Member Posts: 2,774
    here is a thought...

    I have had a error codes w/ similar style boilers and they amount to air in the system. The air bubble may cause this sensor to read higher that it should. The air on the boiler (Smith GC160)  would congregate at the top of the unit. Is there a way to bleed air directly off the top of the boiler? Is there a bad hy-vent or a spirovent that is clogged?
  • panmanpanman Member Posts: 82
    re- tom and Kcopp

    Tom where would i go to find NTi tech support on this site? Kcopp, Thanks for your input. If i had air in the top of my boiler why would it only effect the boiler in cold weather (below zero). why after error code and sitting an hour, why would it only run i cycle? Boiler as cool as it gets after being off an hour. Thanks - Peter
  • TomTom Member Posts: 458

    I went to the main page and searched the forum for nytechsupport and it gave me the ability to contact him as a user.
    Montpelier Vt
  • meplumbermeplumber Member Posts: 678
    Gas Vaporization Problem??

    What you are experiencing is an ignition problem.  This could be caused by poor vaporization at low temps only.  Is this unit propane or natural gas?
  • panmanpanman Member Posts: 82
    re-vapor/ ignition

    Hey MEPLUMBER, I have a propane NTI150. The ER6 code kicked the other night at 5 above 0. I turned the furnace off then on. I grabbed a piece paper and wrote down what it was reading before it kicked the code again. HERE is what I observed.

    Upon start up the furnace showed ASO code for a second then began to run and gas input was a steady 240 and the furnace water temp gradually went to 145 degrees, After 15 minutes and the first cycle it ramped down gas was 82 and then ASC code appeared, then the ASO code appeared, then seconds later the ER6 code appeared and the furnace shut down. exhaust was clear and sits under a 10foot over hang. Hope this helps. Thanks Peter
  • PlumdogPlumdog Member Posts: 873
    Sounds like Air Switch problems

    I had one that displayed similar symptoms (only when very cold outside). Close inspection revealed droplets of water forming in the air tubing between the intake elbow and the air switch itself. Replaced the switch, but the trouble came back the next cold snap. Figured the frigid air being drawn in (directly to the fan intake) was condensing, and the water droplets were fouling the air switch. So I cut in a tee in the intake pipe so it could draw a mix of cold outside air and warm mechanical room air, and the problem has not resurfaced. Bear in mind that this defeats the "sealed combustion" intent of the design, and may not be suitable for your application. The ASO and ASC are "Air Switch Open" and "Air Switch Closed". The control determines if these signals are out of normal sequence, and throws the error code. The air switch is very sensitive, and rough lite-off can also trigger the problem. 
  • panmanpanman Member Posts: 82

    Thanks Plumbdog, The cold air is definately messing with the airswitch. My question is why when the temp stack sensor is by passed the furnace runs in cold weather. I have a regional tech from my oil company coming as the last choice before Trinity gets involved. I already had a trinity installer/ sales come last year and said it was my circulator being a 15-58 and not a 26-99. I had the 26-99 intalled and is on high to NO avail. i will post the results of what is found by the regional manager. I appreciate the info. Thanks Peter
  • PlumdogPlumdog Member Posts: 873
    That's a different problem

    I think the stack "sensor" is just an overtemp safety switch. You have to find out the actual temp in the exhaust before condemning the switch. But they CAN go bad, and replacement is easy. The temp in the exhaust should not be much higher than the displayed supply water temp, if it is very high, then you have another problem.  
  • PlumdogPlumdog Member Posts: 873

    You have 11 inches WC  gas pressure and not 11 lbs as your post says 
  • panmanpanman Member Posts: 82

    My company tech came last night and called TRINITY support. After going through some questions and answers told my tech to check the computer on the boiler and see what the gas allowance was set at. It was set at the lowest setting, so they bumped it up to 50 the highest setting, which makes sense in cold weather the need for more gas to reach higher temps. We had -20 last night, yup -20. The furnace ran all night and I checked it every 3 hours. But after taking a shower at 6am I checked it and boooom ER6 code. restarted several times, and it would run for a cycle then ASC code, ASO code, then ER6. When it gets above 0 today it will start it will reset after an hour and run all day. Happy new year and thanks to all that help and give their time. Much appreciated. Have a blessed 2014. Peter
  • panmanpanman Member Posts: 82

    I have radiant heat, not baseboard. I also have 2  self purging TACO RMB's that have air relief valves. My low water shut off has been checked. -10 last night here in Maine, and around 11:00 Pm furnace throws the infamous ASC, then ASO, then ER6. Called company tech yesterday, hopefully hear from him today. At some point he said Trinity will sent a tech over if they can't fix the problem. My guess is by the time i get an NTI tech over, the temps will be above 0 and running smooth. lifes chllenges!!!!! Thanks- Peter
  • GaoDengGaoDeng Member Posts: 1
    edited January 2014
    NTI ER6 code in cold weather

    Terry O, thank you for sharing such detailed information which covered most of the points. Coming to the kcopp, have you checked the baseboard heaters for the bleed valves? Air can bleed  from the boiler itself. Often air bleeds from either the topmost part of the system or from the flow valves. There's a chance that the spirovent might not be clogged, but it could happen if the system was very low on water or set on anti-freeze. This is not a complicated problem and can be solved by experts dealing in the oil and gas industry, steel pipe company or manufacturer of major components of boilers.
  • kcoppkcopp Member Posts: 2,774
    Is your....

    LP tank above ground of buried? Im thinking along the lines of what meplumber said about vaporization. The colder it get the less gas vapor is there to be used....this is especially at low tank volumes.

    Your fine at lower boiler temps then you ask it to go to hi fire and the gas isnt there.
  • panmanpanman Member Posts: 82
    LP tank in ground

    Kcopp, my 500 lb propane tank is in the ground. My company tech is now leaning on that the furnace is not getting rid of the hot water quick enough when ramping for the cold. He thinks that the out going hot water copper pipe going to the circulator needs to be 1.5'' .I think spec is 1'' or 1 1/4'' He mentioned my boiler is cycling off too much when it is cold. he said it Should not be shutting off , but ramping down. Thats what you get when you have a 138,000 btu boiler just for an 80 gallon hot water heater.
  • panmanpanman Member Posts: 82
    edited January 2014
    pipe sizing out of boiler

    Well, i went home and measured the pipe coming out of the furnace. This is what i found. 3/4'' copper pipe 6'' straight out of furnace, 3/4'' up for 10'', 3/4'' to (pressure gauge), 3/4'' straight out 8'' to low water shut off. then 1 '' to a 26-99 circulator 14'' over. The main loop is 1'' then reduces to 3/4'' when it brances to RMB's and such. COULD THE 3/4'' PIPING WITH SEVERAL ELBOWS FOR THE FIRST FEW FEET BE RESTRICTING THE HOT WATER WHEN RAMPING FOR COLD WEATHER AND TRIPPING THE ER6 CODE???
  • panmanpanman Member Posts: 82
    edited January 2014

    My company tech said i am getting the ER6 code because of the hot water not getting out of the boiler fast enough. He said that my Taco RMB's were not helping matters and recomended pulling them let the furnace do the out door reset and pump the water straight into the zones rather than running the RMB's which are cumersome and slowing the flow out and return flow. I have pics of my boiler and piping if you search the wall( Radiant Not heating because of pex placement)
  • ykeryker Member Posts: 1

    go into ur sentry controller and turn down full modulation from 240 to 200 and problem will go away and yes piping is the issue
  • mickeypace1mickeypace1 Member Posts: 1
    Just found out from NTI tech that with the T150 and the sentry controller that there is no error code 6. If you get that you have a bad controller. Check the manual for the T150 only and you will see no info for error code 6. I have spent thousands of dollars on this unit and now I find this. I could have put in a brand new unit by now. Will install new sentry unit next week and see what happens. WHAT A PAIN.
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