[RFI] Trane Heat Pump RFI

John Pelham john at radiophile.com
Wed Apr 14 14:59:45 PDT 2010

I need a replacement heat pump for my 2nd zone. Having read here about the 
RFI problems associated with variable-speed blower motors and their PWM 
drive, I told my HVAC contractor that I would not accept a variable speed 

He proposes a system with a Trane 4TEH3F24 air handler. This unit does not 
have a variable speed motor, yet it is 15 SEER, which will allow me to get 
the Federal tax credit.

The Trane brochure says this model has four fixed speeds. I have examined 
what I can find by Googling this model, and the blower motor is connected 
directly to the 240VAC source, but there is a control wire that goes to an 
"ER" (electronic relay) unit. I can't find a schematic of the ER unit on the 
Internet. I have e-mailed a Trane contact given to me by my HVAC contractor, 
and asked for information on, or a schematic of, this ER unit.

Does anyone here have experience with a Trane inside air handler with "TEH" 
in the model number? Are there any RFI problems?

Thanks and 73,
John, W1JA 

More information about the RFI mailing list