On Dec 1, 12:14*am, Deodiaus wrote:
On Nov 30, 11:10*pm, Deodiaus wrote:





I have a York furnace.
model # P2MPD14N08001C
It seems as if the high limit switch is problematic.
It has a rating of 170-30
It is made by Texas Instruments. patent no 5144274
the numbers
1NT17L-2303
L170F-30
025-29041-007A
9418

meaning it shuts off at 170 deg F and comes one when the temp drops by
30 deg F.

The problem seems to be that the downstairs of a 6000 sq ft house does
not get warmer than 67 deg F on a 30 deg F night.

We have about 4 units, in a 2 story house.

Does anyone have any good and cheap suppliers for this part.
I called Grainger, but they could not tell me the cut off temp on the
York high limit switch in stock.

The furnace does come on and seems to work.
It is just that the house does not get warm enough.
This is a 17 year old house in TN- Hide quoted text -

- Show quoted text -

Since you said furnace I'm guessing gas? If it's running the problem
is not the hi-limit switch. If it shuts down before the thermostat
stops calling for heat then it might be the hi-limit switch. So is
the temp at the thermostat reaching the set point? And the problem is
that another part ofthehouse is too cold?

You don't mention any zone controls so we're talking about a sngle
furnace, single thermostat set up, correct? A single furnace on that
large a house must have a number of flow dampers on the vent ducts.
They would be close to the furnace. They probably need adjusting.
They will most likely need to tweaked everytime you switch from
cooling to heating or back.