Did I break it? ...Heat pump

Specific Inspection Topics Inspecting HVAC Systems
1

Was testing a heat pump on the cooling cycle today on an older home. There was no manufacturer’s plate on the unit but I would guess it was at least 15 to 20 years old. It looked like a Nordyne unit

This is a vacant house that has been vacant for about a year

I let the cooling run for about 30 minutes or more. I decided to shut down the cooling and test the emergency heat…I turned the thermostat to the “off” position… A few seconds later I turned the thermostat to the “Emergency” setting from the “Normal” setting on this older thermostat…then I turned the thermostat from “off” to “heat”…and turned the thermostat up over 80 degrees…

Buyer was outside and says he heard a muffled sound like a muffled backfire…Unit stopped working and would not re-start…Did I break this unit?

2

Looks like it was at the end of its life .Failed in testing ,

3

Yes you broke it and need to buy a brand new unit; at least that is what the seller will claim did you turn it back to normal cool and wait for the timer to time out and if it did not re-start it failed during testing end of story

4

I turned it back to “Cool” after about 10 minutes of trying to figure out what happened. I kept it on Cool for about 30 mintues and it never re-started…so I turned it completely off before I left.

The buyer said that he smelled a burnt smell at the unit, similar to something electrical burning out

I’ve never heard of a unit blowing from testing the Emergency Heat…Anybody ever have this happen to them?

5

The compressor does not operate when in the emergency heat mode only in the normal heat mode and the cool mode. If the buyer heard a noise while outside it was probally the reversing valve. Did it trip the breaker or did you check

6

Lots of package units here Charley.

Blew out the electric heat and blew a fuse…

…more than likely.

Fox, there are fuses inside the unit (if you checked breakers and seemed OK etc…)

7

Yes. I know about the emergency heat…I was just wondering if I blew something by turning on the Emergency Heat right after testing the Cooling part of the Heat Pump…I thought that maybe I did something wrong by waiting only 5 or 6 seconds before going directly to Emer. Heat…None of the exterior breakers tripped

8

No you did nothing wrong going to em heat it just turns off the compressor unless the unit was improperly wired which I have seen. Was this a package unit or a split system. There should have been a breaker in the main panel I see on a lot of units a 60 amp breaker at the unit which simply is a disconnect switch and a 30 or 40 amp breaker in the panel that protects the conductors and the unit

9

Failed during testing . end of subject . that’s all folks . did nothing wrong

10

Sounds to me that a capacitor could have clown in the heatpumps which would allow the unit to start outside

11

What if I want to act like Larson and keep this thread alive I’m trying to get to 40,000 post about nonsense. LOL:roll::wink:

12

Never going to happen you are a nice guy who knows right from wrong.

13

LOL ok Charley go for it , Hmm lets see
So Charley what fact do you have to prove your statement ?
Do you any any documentation to prove this ?

14

We all know it is always the governments fault

15

:d:d:d:d:d:d

16

Blame on the liberals i know they wanted a free one

17

Charley be nice. I already agreed with you once today. :roll:

18

Was the back-up heat Gas OR Electric?

If gas the outside AC unit should not come on in emergency heat.

Wonder if you switched from cool to heat before the system had equalized (on / off) and blew the compressor / burnt smell.

19

Why would it blow? It just cycles on internal overload till it equalizes…

20

David - I have not seen it a lot BUT I’ve actually seen 2 blow the compressor valves or terminals out, from too rapid cycling.