York Warm air furnace problems

GW

You lowered the speed when you had a 99 rise?

BillAllen

no the tech did.

Harvey Ramer

Maybe he lowered it to keep the blower motor from burning up. What was the ESP on the furnace?

BillAllen

.30

BillAllen

That would include filter, blower, coil ductwork. At one point the temps reduced to 130 after 7 minute call with cover blower cover off. The furnace was oversized some vents were closed as well. Gas pressure little high. Starving for return air. When you open the front blower cover system runs normal with no error codes, temps drop, ran well through cycle.

Harvey Ramer

When measuring the ESP on a furnace, you have to insert the one probe between the filter and the blower and the other probe immediately at the exit of the furnace, before the ac coil.

.3 does not sound like an accurate measurement considering the symptoms the furnace is displaying.

GW

.3, extremely unlikely, mayne with an undersized furnace and a big filter and no ac, that's even low for just the duct work.

Just drill the blower compartment and pull the high limit for best results

BillAllen

To follow up. Its been over a week no call back. No error flashes.
The probes were placed between filter and blower and other one after coil. It was .3.
The system is over sized and the return air is under sized. Again, when I removed the blower/module cover the system runs much better. Starving for air. Right now were good. Time will tell if I need to make other alterations.

Tinman

You aren't runnng the furnace with the blower door removed, are you? There are all kinds of potential problems with that. Safety issue with an exposed blower wheel spinning in excess of a thousand rpm, pulling a negative on a room with gas fired equipment, and overloading a forward curved blower wheel to name a few.

BillAllen

No no. Do not panic! This was just to see what performance I might see with added return air. If I cut in a return it will not subject a pilot or effect gas equipment.

GW

I'm afraid your numbers aren't correct. There's no way you have a .3" wc tesp, especially if you have small ducts.

When you type "Again, when I removed the blower/module cover the system runs much better. Starving for air", you may get some panic.

BillAllen

Maybe but the manometer reads .3 3 times as I stated where I inserted the probes and that by the tech. Did I say ducts are too small? I only assume they might be too small but really the furnace is too big. Remember the homeowner had 2 vents shut without my knowledge.
At the moment the system is ok with the gas press adjustment. We will continue to monitor it.
There are no error codes/flashes for about a week now at normal operation.

GW

If the furnace is too big, that normally translates into the ducts being too small.

The tech guy must be sticking the probe in the wrong spots

In any case I'm glad it's back to normal.