Is Heat Pump suppose to come out right away

[zotmeister]

I still don't quite understand the physics of extracting cold air from the outside (heat pump) and using that to provide heat. My assumption is that heat comes from electric or gas heating of some sort. Its also strange ss that outdoor unit is called a heat pump. In the west coast, we just called that an A/C unit and its never on when the heat is turned on??

[escanlan]

Originally Posted by zotmeister

I still don't quite understand the physics of extracting cold air from the outside (heat pump) and using that to provide heat. My assumption is that heat comes from electric or gas heating of some sort. Its also strange ss that outdoor unit is called a heat pump. In the west coast, we just called that an A/C unit and its never on when the heat is turned on??

Don't worry too much about the physics behind it until you get a good high level understanding of the heat pump concept. Here is a really good interactive video to view. It has options as needed with additional good presentations on other related aspects.

Pacific Air Systems - How does a heat pump work?

[Whatsthenews]

So- a related question from someone who has very little knowledge of heat pumps, having lived elsewhere.

I appreciated the concept of pulling heat from the outside air, but not that ALL heat pumps had an auxillary source of heat within them

My parents are in a home here in NC that has an old heat pump.
Last year they had problems. It was blowing cold air when temps were below about 45F.
Guy came out and told them it was almost dead and a new system would be about $3000.
Whatever he did didn;t seem to make much difference, but I wasn't there at the time and parents are in their 70s and don't ask questions.

It's doing the same thing now.

Only managed to get the temp' in the house up to around 60f yesterday when it was around 40F outside.
Eventually they turned it off and put an oil filled heater on.

Does this mean that the aux' heat isn't coming on, that the unit isn't working efficiently in heat pump mode, or both-LOL ?

Thanks

[escanlan]

Originally Posted by Whatsthenews

So- a related question from someone who has very little knowledge of heat pumps, having lived elsewhere.

I appreciated the concept of pulling heat from the outside air, but not that ALL heat pumps had an auxillary source of heat within them

My parents are in a home here in NC that has an old heat pump.
Last year they had problems. It was blowing cold air when temps were below about 45F.
Guy came out and told them it was almost dead and a new system would be about $3000.
Whatever he did didn;t seem to make much difference, but I wasn't there at the time and parents are in their 70s and don't ask questions.

It's doing the same thing now.

Only managed to get the temp' in the house up to around 60f yesterday when it was around 40F outside.
Eventually they turned it off and put an oil filled heater on.

Does this mean that the aux' heat isn't coming on, that the unit isn't working efficiently in heat pump mode, or both-LOL ?

Thanks

The ability of the heat pump to provide heat is a function of its balance point. You can obtain a general description of balance point at that WEB link above. The balance point of each model unit depends on a number of different factors. If you want to read some of the technical aspects of this, and try to calculate your unit's actual balance point, then this is a fairly good explanation without getting exceedingly technical Heat Pumps.

The supplementary heat source for your unit needs to be known so you can determine what is occurring. If you have no other supplementary heat source available then electric heat strips should have been installed in the unit to handle the colder conditions. The size of the supplementary heat strip capability is also determined by your local area conditions. For example in areas that mostly stay warm enough not to need supplementary heat, except in strange weather occurrences, the heat strips might be minimal in heating capability. The smaller the capability the less the cost of the heat strips. In other areas the heat strips could wind up being high draw, high heat, multi-stage strips where each strip in the stages are activated as necessary to provide indoor heat.

In your Parent's case the unit is older and the issue could be a number of things. First you indicate that the system is raising the temperature but not to a level more than 20 degrees above outside temp. So it appears the heat pump function appears to be functioning but is not able to keep up with the needs inside the home? Possibly they had a secondary heat source and when the original HVAC system was installed the heat strips were not determined to be necessary and not installed to save money? It could be that the heat strips are wearing or no longer functioning and are not able to provide any or the amount of heat they once were capable of? It could also be that heat strips were never installed or failed long ago and now you are seeing the results?

At this time I would not necessarily suspect the HVAC company is trying to play games with estimating and advising a whole new system is needed. We don't know the age and actual condition of the system now in place. Is it possible that the system is in such a condition now that trying to repair it is no longer economical and replacing it instead is a better alternative? I had a seven year old Lennox system (heat pump) where the exterior coil broke in 7 places in their specially engineered shock mount (poor design). The cost of replacing just the coil was just about the same as replacing the entire exterior compressor unit. Trying to repair seven coil breaks and hoping they hold still would have cost half of a new unit. At that point it was a no brainer to replace the whole unit which came with brand new compressor and coil warranties for another long period. Maybe your HVAC Tech was also looking forward to save your Parent's money?

What you need is another HVAC company in to check it out and provide repair/replace estimates. You might also want to look at the home itself to see if there is excessive conditioned air loss that you can repair. That could potentially reduce the need for a larger unit, more expensive HVAC equipment, etc., to keep the home comfortable later.

[Whatsthenews]

Originally Posted by escanlan

The ability of the heat pump to provide heat is a function of its balance point. You can obtain a general description of balance point at that WEB link above. The balance point of each model unit depends on a number of different factors. If you want to read some of the technical aspects of this, and try to calculate your unit's actual balance point, then this is a fairly good explanation without getting exceedingly technical Heat Pumps.

The supplementary heat source for your unit needs to be known so you can determine what is occurring. If you have no other supplementary heat source available then electric heat strips should have been installed in the unit to handle the colder conditions. The size of the supplementary heat strip capability is also determined by your local area conditions. For example in areas that mostly stay warm enough not to need supplementary heat, except in strange weather occurrences, the heat strips might be minimal in heating capability. The smaller the capability the less the cost of the heat strips. In other areas the heat strips could wind up being high draw, high heat, multi-stage strips where each strip in the stages are activated as necessary to provide indoor heat.

In your Parent's case the unit is older and the issue could be a number of things. First you indicate that the system is raising the temperature but not to a level more than 20 degrees above outside temp. So it appears the heat pump function appears to be functioning but is not able to keep up with the needs inside the home? Possibly they had a secondary heat source and when the original HVAC system was installed the heat strips were not determined to be necessary and not installed to save money? It could be that the heat strips are wearing or no longer functioning and are not able to provide any or the amount of heat they once were capable of? It could also be that heat strips were never installed or failed long ago and now you are seeing the results?

At this time I would not necessarily suspect the HVAC company is trying to play games with estimating and advising a whole new system is needed. We don't know the age and actual condition of the system now in place. Is it possible that the system is in such a condition now that trying to repair it is no longer economical and replacing it instead is a better alternative? I had a seven year old Lennox system (heat pump) where the exterior coil broke in 7 places in their specially engineered shock mount (poor design). The cost of replacing just the coil was just about the same as replacing the entire exterior compressor unit. Trying to repair seven coil breaks and hoping they hold still would have cost half of a new unit. At that point it was a no brainer to replace the whole unit which came with brand new compressor and coil warranties for another long period. Maybe your HVAC Tech was also looking forward to save your Parent's money?

What you need is another HVAC company in to check it out and provide repair/replace estimates. You might also want to look at the home itself to see if there is excessive conditioned air loss that you can repair. That could potentially reduce the need for a larger unit, more expensive HVAC equipment, etc., to keep the home comfortable later.

Thanks!
The outside unit was frozen-literally thick with ice as the board that controls the defrost wasn't working!
Plus the wire that connects the back up heat was disconnected.

So pleased they don't need a new unit at this point anyway!
Cost $400 total.