HVAC Troubleshooting

[nate2953]

Hello all, I am always quite impressed when I come across the DIY/Troubleshooting knowledge of this community.

I have a heat pump cooling/heating system in my house. We have owned this house for 2.5 years. (Built new in 2017) and now that cooler weather is upon us, we’ve been using the heat more.

We have two thermostats that appear to work independently(in the past the master bedroom thermostat would call for heat or a/c in the master bedroom even if the thermostat in the main living area was turned off. Same with heat, in the past when we wanted to heat our master bedroom at night, I would just go to the master bedroom thermostat, turn it to heat, set the desired temp, and regardless of the other thermostat the master bedroom would be heated to the desired temp.

Fast forward to now, when the master bedroom thermostat is turned on to heat, and set for a few degrees above the current temp(and the main living area thermostat is off) there is no heat/air coming out of the registers and after a few minutes the aux heat turns on, and still no air/heat from the registers.

When I turn the main living area thermostat to heat/target temp above current temp, I can feel air coming from the ducts.registers in the master bedroom.

The last two winter seasons I think I remember being able to run the master bedroom thermostat at 68° and the rest of the house at 66° with no issue, but now it seems I can only get the master bedroom to pump heat if I call for the rest of the house to pump out heat as well.

I’ve removed and switched the thermostats and when I take master bedroom thermostat and put it in the main area, and the main area thermostat on the master bedroom thermostat there is no change in the heat. So I think the thermostats are in working order.

I’m not sure if there are two control boards, and maybe the one control board for the master bedroom is kaput and needs replacing?

I have an HVAC tech coming on Friday, but I want to see what the hive might suggest just so I am prepared.

Thanks and whatever additional information is needed, just ask!

 

[Sunset]

I don't have a heat pump. But this is somewhat interesting.

In my situation, I have 1 furnace, and if I had 2 controls, both would still control the 1 furnace and heat would blow into the entire house.

I don't understand how in your case, you expect heat to blow into the bedroom, but not the rest of the house. Is there a separate blower and duct system for the bedroom ?

 

[nate2953]

I always assumed we had dampers that were controlled to open/close ducts based on how the last two years of heating/cooling went. In the summer we could cool the master bedroom independently of the rest of the house/same with heating. We have just one outdoor unit and one air handler as far as I know.

 

[nate2953]

The heat pump/air handler work because the rest of the house is 75° right now, but I’m wondering if some the the mechanical/electrical stuff that opens/closes the dampers or whatnot aren’t working right?

 

[Masquernom]

Yes, there are residential systems that can be set up to divide a house into multiple zones. They use dampers to direct the airflow to whichever room has a thermostat that's calling for heat or cooling. Sounds like you have a similar setup and some component isn't working right.

 

[iloveyoga]

It sounds like one of your dampers is not working, we have that system with forced air heat, but I would think the dampers are the same, they have electronics in them to open and close as needed.

 

[ShokWaveRider]

2nd Damper Problem. There is usually a separate control boad somewhere for the damper control.

 

[nate2953]

Thanks everyone, I just wanted to make sure I wasn’t crazy and misremembering how it all worked last year.