DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   HVAC (
-   -   Problem with RUUD CH/A blower (

imabballer 01-06-2009 06:14 PM

Problem with RUUD CH/A blower
I am having a problem with my RUUD electric heater's blower. The heater is about 10 years+- old and is model # UBHA-21J15SUCAI. It has three heating elements which all work ok but I am having a very frustrating problem with the blower. Occassionally when the thermostat tells the heater it's time to turn on the heating elements will heat up and the blower either won't turn on, and the heating elements will eventually just turn back off (after smelling like their burning), or the fan will finally turn on (making the whole house smell like the burning heating elements) until it warms the house up, and turns off a short while after the heating elements have turned off and cooled down. Other times the heater works perfectly and the fan engages with the heating elements. To keep from burning up my heating elements I have started leaving the fan in the "on" position on the thermostat so there is always airflow when the elements turn on.

I have thought that it might have something to do with the fan motor but the blower works perfectly with the air conditioner, it just has problems with the heat. Although, I have noticed a funny sound from the blower when it is running and I have the cover off of the unit, it's almost like it hesitates every once in awhile but the airflow never really changes, it just sounds a little funny, almost like the voltage fluctuates for a split second. Anyway, I think it might have something to do with the switch that turns the fan on with the heater but being absolutely incompetent with electrical problems I'm not sure what part is supposed to turn the fan on. I am attaching my wiring diagram if anybody would be so kind as to offer a guess at what might be the culprit and if it's not clear enough let me know and I'll try to upload it some other way.

Oh, also, at the suggestion of my father-in-law I have changed out the blower relay but it didn't help the problem.

Thanks in advance!

imabballer 01-09-2009 12:23 PM

Does anybody think it could be the control transformer?

JohnH1 01-09-2009 02:55 PM

It is most likley what is listed as the heat relay. They are sequensers bringing the blower on with 1st stage heat and then additional coils after. then in revers upon shut down. It could also be the normally closed switch on the blower relay failing but is more likley the sequenser.
Hope this helps.

All times are GMT -5. The time now is 02:20 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1