Replacing blower motor in E2EH-015HA

[tbond]

My mobile home is a 2000 model with a Nordyne ac and electric furnace. Thru the years we have several problems one occasion the a coil froze and short the low voltage card, that was replaced. Couple years later it happened again and had it worked by a HVAC guy. I dont recall what all was replaced but he removed the low voltage card from the system. It worked fine a few years then the drain pan wasnt draining out and it overflowed and shorted out the fan relays and caught fire. Thanks to my spouse we didnt attempt to repair for 2 years. I replaced the fan relays 621898 and 621899 after some searching for the wiring diagram. Instead of buying a new wiring harness I purchased the wire at Home Depot to rewire it. I may need it to be looked over to make sure i have it wired correctly. After rewiring and installing a new thermostat. The Fire shorted out the old one with 230 volts. I set the breakers to on and using the thermostat to fan on. The blower caught fire and stopped. The original motor was an emerson part number 621675, 1/3 Hp 960 rpm with a 4 inch shaft, the replacement is emerson 1972 1/3 hp 1075 rpm with a 5 inch shaft. My question is with the shaft being an inch longer and using a torsion flex ring will it hurt to cover the vents on the motor and will affect the vibration with the ring mount not being mounted in the center of the motor body. Also should this motor be set for clockwise or ccw rotation, as it is in a downdraft system.
Second question is should I try to reinstall the low voltage card back in to the system and what would the advantage be or disadvantage be if I don't reconnect it.

[tbond]

Having looked at the website and choosing the generic motor 1972 on the website it states that it requires G21-930 run capacitor, which is rated at 5 mfd 370v. On label for the 1972 motor it states needs a 7.5 mfd 370 volt Capacitor.

[Robert]

Was the wire you bought high heat rated for 105*C ? That is a must for furnace wiring.


Will look at other and reply back in a few.


Thanks,
Robert

[tbond]

Yes the wire was THHN rated.
Realized that the shaft length was not a problem. As far as the rotation is concerned the motor was set on CW and it blows air the correct direction. But, to be honest in trying to understand whether it shaft end or the hub end I couldn't find how to tell. But it works correctly that's all that matters.
Got it installed running fine. Only issue is that the fan runs all the time even when switched off at the t-stat. Thinking the issue is maybe loose connection at one of the blower relays. I had to home engineer a way to connect them cause it takes a pigtail wire that goes from the NO to the NC relays. Those little wire connectors are impossible to find without buying the harness kits.
I have heat now that was what I was aiming for, the AC will have to be checked out at a later date. From what I surmise the low voltage card that was installed originally in the system is so you have two different speeds for the fan when heating or cooling. works without it but I'll eventually wire it back in.
Thanks for your reply and if I have any more questions I'll be back. I appreciate your wealth of knowledge here, having read over some of the other posts I gained a better understanding of it all.

[Robert]

We sell the motors, wires, connectors, molex plugs, molex plug pins, etc. Make sure the THHN wire IS rated for a minimum of 105*C .

There is shaft end SE and lead end LE. SE is the end with the shaft and LE is the opposite end.

Was the motor you bought rated for a mobile home system ?

Sorry for delay in getting back, got side tracked with my time and forgot. Memory is not where it once was,LOL.


Thanks,
Robert

[tbond]

Yes the wire is THHN rate at 105C. The blower motor is the emerson 1972. Works very well too, hook up was fairly simple and straight forward. The only difference between that and the motor I was replacing is the old one was 4 speed new one is 3 speed. Only difference in wiring it up was white wire to orange and did not use the yellow wire for medium low speed. I used high temp male and female disconnected to connect the wires to the molex plug from the old motor.
I also installed a Honeywell programmable thermostat in the system that should help on heating costs.
Hopefully, this system will be tuned up for a while and will perform well it certainly is heating well so far. Am glad that this last time we had the fire inside that the only thing that was burned up was the fan relays and some wiring, the heating elements were shorted out and replaced in 2003. The main cause of the fire 2 summers ago was the drain pan under the A coil wasn't draining properly. The tubing going down to the drain line was flexible and developed a sag in it. Am replacing that with solid PVC and elbows this coming spring before using AC. If you could explain how a drain trap would help keep the drain pan from overflowing. Also, in the coming spring will definitely have to use a can of the low foaming coil cleaner to make sure that A coil is nice and clean.

[Robert]

On downflow electric furnaces, the motor ~pulls~ the air through the a-coil instead of pushing it which creates a negative pressure.

Without a trap, the negative pressure will pull outside back up through the drain line which restricts condensate from being able to flow out the drain.

Use 3/4" for drain line.


Thanks,
Robert

[tbond]

That does make a lot of sense to me now. The trap should be placed below the floor level then? I will definitely make sure that one is in place the original setup had a flexible hose running down to the 3/4 PVC pipe which had a 90 degree elbow turned down, but a lot of times it didnt seem to drain very well. I take it that the trap prevents air from outside from coming up and keeping the water flowing thru. I will check the traps and find one before the spring get here and the AC is needed. Again thanks Robert for the information.

[Robert]

You're very welcome, happy to help.

Here's one we sell that works well and goes at end of drain line:

http://www.aberdeenhomerepair.com/store ... esults.php



Thanks,
Robert