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[Brauma]

My HVAC unit has a variable speed fan. But the way my system is working, the fan just runs on its slowest speed. Is there any way to control it? It would be nice to blow this nice hot air a little faster.

The guy who installed my Hardy installed a Honeywell VisionPro TH8000 thermostat and has the Hardy as the Emergency Heat mode. In other words, I just have this one thermostat on my wall instead of two.

Thanks

[Scott7m]

Variable speed units are a pain

Try this tho, turn the breaker off to the heat pump, then turn your thermostat to normal heat and see what happens

[Scott7m]

However if he installed it where the pump kicks on and off this won't work

[AirForcePOL]

On my furnace there is a chart on the door of the furnace.  It will show you what terminals to plug the fan fires into to achieve different speeds when in heat/cooling mode.  You might look at that and see if yours is the same.

[Scott7m]

On my furnace there is a chart on the door of the furnace.  It will show you what terminals to plug the fan fires into to achieve different speeds when in heat/cooling mode.  You might look at that and see if yours is the same.

I think his is truly variable, not just different speed options

They ramp up for like 30 seconds before they get to top speed

But maybe his has that chart, I was thinking pf a truly variable though

[AirForcePOL]

Gotcha...I've never messed with one of those.

[Scott7m]

Gotcha...I've never messed with one of those.

Consider yourself lucky lol

I don't like em

[Brauma]

I think mine is a true variable. I dont see a wiring diagram concerning the fan. Mine has this annoying habit of shaking the whole air handler when it starts. Sounds like the thing is coming apart. The guy told me that was the fan oscillating till it finds its happy speed. It's been 7 years and I still haven't gotten used to it. 

[yoderheating]

The only way to really make a variable speed fan work correctly is to use an aquastat instead of second thermostat or wiring it the way Brauma describes. There is a way to turn up the low speed of a variable to around 30% but that is the best it will do if wired in the traditional manner. Variables are normal in many new systems, I run into them all the time. I don't mind them, the digital communicating systems are the ones to be afraid of.