is freezing up normal for a heat pump?

[greybeard]

No mine. The outside unit was frozen up so bad the fan was rubbing the ice on the coils.
Temps been low 30s in daytime and low 20s at night.
In the shade on North side of the building it never sees the sun.
It took over 8 hrs of running a torpedo heater on it to thaw the ice.
Are they (heat pumps) all like this?
Trane

 

[sstterry]

I have seen this happen in the summer when the coolant gets low. But I have never seen it in the winter.

 

[bird dog]

Most have an internal heater that keeps them from doing this. Mine shuts down while the system defrosts. Takes about 5 minutes. The temperature decides how often it does that.

I would think you have a malfunction.

 

[Kingfisher678]

From what I here you need to be on emergency heat w cold outside temps

 

[Caustic Burno]

From what I here you need to be on emergency heat w cold outside temps

My AC guy disagrees with that, says the heat pump is less efficient under 30 and needs help with an auxiliary strip.
That is still more efficient than the heat strips alone.

GB I have a 4 ton Trane and has never frozen as described.
Sounds like it's not going into defrost.

 

[damengineer]

I have a ground source heat pump and never have to worry...

 

[simme]

Heat pumps have a reversing solenoid that reverses the refrigerant flow momentarily ever so often in cold weather. Normal heating operation is to move heat (BTU's) from the outside air to the inside coil in the house. The reverse of the cooling mode. Cooling mode removes heat from the inside coils and puts those BTU's into the outside air. In the heating mode, the outside unit/coil gets colder and colder until the moisture freezes on it. There is an electronic board that controls the defrost cycle to momentarily reverse the refrigerant flow and run the system as an air conditioner - putting heat into the outside coil to defrost it. Uses that reversing solenoid valve and that electronic board. The outside fan shuts off while the compressor and inside blower run. Goes back to heating mode after it defrosts. Probably the electronic board is bad, maybe the solenoid.

 

[kenny thomas]

Greybeard, there is a defrost cycle that can be set to different times from. 30 minutes to I think 2 hours. Most likely to cause problems when its barely above freezing outside. That switch either needs the time adjusted or a new switch

 

[TennesseeTuxedo]

I have a ground source heat pump and never have to worry...

Damm Engineer.

 

[HDRider]

Most have an internal heater that keeps them from doing this. Mine shuts down while the system defrosts. Takes about 5 minutes. The temperature decides how often it does that.

I would think you have a malfunction.

Mine does that too. Mine is on the west side of the house, so that helps

 

[HDRider]

From what I here you need to be on emergency heat w cold outside temps

We have been to -3. It has stayed on the normal setting the whole time. I hit 70 inside during the cold juts like I do normally. We have been in single digits now for about 2 weeks

 

[jltrent]

Needs a new sensor. Looks like a latter model Trane, so you probably can still get one. If a heat pump system does not meet a certain SEER rating parts are getting hard to come by. Uncle Sam wants you to have a new complete system with a high SEER rating to cut down on energy consumption. This is like what has happened to washing machines, (water consumption) and a lot of other items. My mothers older washing machine timer starting malfunctioning, so I figured it would be an easy find. I had to dig deep in the interweb to find one old stock and pay a ridiculous price. At her age learning to operate a new one would be hard.

 

[D2Cat]

Around here we quit using the heat pump at about 32-35 deg. Thermostat has cool...heat...emergency. The emergency is elec. resistance furnace. Once the switch is to that mode the heat pump is not in the circuit.

We heat with Osage Orange. Three to four cords will heat the house to any desired temp for the winter and those high dollar heaters are never used.

 

[Mrcopier]

Around here we quit using the heat pump at about 32-35 deg. Thermostat has cool...heat...emergency. The emergency is elec. resistance furnace. Once the switch is to that mode the heat pump is not in the circuit.

We heat with Osage Orange. Three to four cords will heat the house to any desired temp for the winter and those high dollar heaters are never used.

One of mine went to emergency heat and we turned it off and just shut that part of the house down. That emergency heat is VERY expensive

 

[greybeard]

The unit was installed new in 2015 or 2016.
I told him about the emer heat setting and he said he saw it on the thermostat but didn't know what it was so he didn't try it. Young fella, 24 yrs old, works in the medical profession and not really a trouble shooter type, but most folks weren't at early ages.

Very possible there are electronic sensor or board problems.. the outside unit had 1 1/2 feet of water on top of it in 2017 but had been working ok up until this record temp thing.

Thanks everyone.

 

[Little Joe]

Either the defrost board is bad or the temperature sensor for the defrost. I've been an HVAC contractor for 20 years, I always tell people that if it's gonna stay below freezing for several days turn it to Auxillary/ Emergency heat. Every time the unit has to go into defrost it is basically turning on ac and then running the strips to offset the cold air at which point you're running a compressor and strips. Also most digital thermostats are designed so that if room temperature is 3 degrees below setpoint it automatically runs strips,or if the thermostat has been calling for heat for more than (I believe 15 minutes ) and has not raised the room temperature it kicks on the strips. Trust me whether you realize it or not when it's as cold as it has been your unit is running the strips alot and if you still have on the heat pump your running a compressor too. Another problem I've run into numerous times when people are running the heat pump in weather like this is the ice or snow builds up around the fan blades and burns up the fan motor, the defrost doesn't thaw out that part well, it is designed to thaw out the coils.

 

[Mrcopier]

My heat pump has been running non stop for 10 days, it stopped for the first Time yesterday. It needs a Medal of Honor, would love to but it a beer!!!

 

[TexasBred]

No mine. The outside unit was frozen up so bad the fan was rubbing the ice on the coils.
Temps been low 30s in daytime and low 20s at night.
In the shade on North side of the building it never sees the sun.
It took over 8 hrs of running a torpedo heater on it to thaw the ice.
Are they (heat pumps) all like this?
TraneView attachment 2486

GB I know nothing about them other than owning one. I'm told that outside unit is supposed to go thru a defrost cycle periodically.

 

[Little Joe]

GB I know nothing about them other than owning one. I'm told that outside unit is supposed to go thru a defrost cycle periodically.

They have timers that can be set for 30,60or 90 minutes. We usually set them at 90. Doesn't mean it will go into defrost every 90 minutes but it will check to see if the defrost thermostat is closed to see if it needs to go into defrost. I've had people call me that's never owned one and think their unit is on fire because of the steam coming off of it or that their fan motor went bad because it shuts the outside fan off in the defrost cycle.

 

[1982vett]

All I'll add is I don't recall seeing ours froze up at all this time. Maybe I was just to concerned about walking on ice and slipping to notice.

Also, we have a Honeywell programmable thermostat. Doesn't have an emergency heat setting like the older setups. I suppose it takes care of that itself. I do remember my first experience with one freezing solid in 1982. Technician said it was wired up wrong and heat strips weren't coming on. I would think by now installers would know the ins and out of stuff like that.