"Rob" wrote in message news:5Rtyd.16567$dv1.5410@edtnps89...

"TURTLE" wrote in message
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wrote in message
oups.com...
Thanks for the help again Turtle.
I can run the fan in ON position and it keeps running continuously
without stopping. As a matter of fact, that is how I have it now until
the service tech arrives. I also changed the filter last month.

The diagnostic light on the ECU remains OFF, so the ECU is not noting
any problems with its sensors.


Tony


This is Turtle.

This still does not prove anything.

#1 first when you turn the thermostat to cont. fan mode it shifts the motor
to a higher speed winding and a motor can be burnt up on heating / low or
med. speed and still run fine on high speed for cooling.

#2 The heating mode of the furnace relay board or relay system will run low
or medium speed to run the heat and high speed for cooling mode. You can have
bad bearing on a motor and start cutting out on low or medium speed but run
fine on high speed for you have more horse power on high and can over come
the drag of the bearings. Direct drive blower motor have different house
power on each speed as here : [ High Speed 1/2 H.P. 1075 R.P.M.'s ] [ Medium
1/3 H.P. 975 R.P.M.'s ] [ Low Speed 1/4 H.P. 875 R.P.M. ] .

#3 Most all older blower motors have 3 or 4 speed types have completely
different motor built into them. A 4 speed motor has 4 different motors built
into it. You can burn up 1 or 2 or three of the speeds and still have 1 or
more that will still work fine. So your testing just showed that high speed
of your furnace is ok but never looked at heat speed or medium speed as it
being good or not.

#4 Now you have high speed running for the tech to see but when he gets there
, tell him to check the problem speed of medium or the low speed set for
heating.

#5 Now you still don't know what it is but you can use the high speed to heat
with till he gets there.

Can't the 'Fan-on' speeds be changed to match the speed during the heat cycle?

This is Turtle.

Yes it sure can be done. I do them all the time by putting the heat and cooling
on the high speed but have to watch the heat rise of the heat by having the high
speed blowing on the heat mode. There is speed selectors on most all gas or
electric furnaces and you can select any speed you want for heating or cooling
modes. There is only on gas furnaces over 35 years or older before you just have
one speed for both and have no selection set up.

Now if the low or medium speed is running the motor hot due to bad bearing. You
have about 6 months to 2 years before the high speed will not work either and
catch you when it is freezing weather and want heat to not freeze to death. Fix
it now when you have time to work on it and not wait till your in trouble and
need it NOW type job. Now jobs cost a whole lot more than a job done in routen
work done on the furnace. It's like a water pump leaking water on your car and
then you just put it off till your going on vacation and get in the middle of no
where and need a water pump changed out. Done at a regular tiome it would cost
about $150.00 and on the road with a wrecker charges and Billy & Bob auto
service could cost you about $500.00+ in some cases. The furnace is the same
thing. Fix it now when you have time and service to do it on a timely manner.

TURTLE