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NY to ban natural gas in new construction.

CrustyJeep said:
It's not just that. The colder it is, the less heat there is to extract from the air, and the more work (KWH) it takes.
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Well I suppose the temperature differential also gets a lot higher the colder it gets outside. Lot bigger delta T on winter temps when compared to summer A/C operation temps...

two stage cascade system heat pump lol
german engineer's wet dream
 
[486] said:
ain't so much efficiency dropping as they just stop working because the evaporator fills with liquid and resistive heat takes over
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I've never heard of that happening. I mean, of course it would happen at a low enough temperature, but I think it would have to be very low. I think it would destroy the pump.
 
CrustyJeep said:
I've never heard of that happening. I mean, of course it would happen at a low enough temperature, but I think it would have to be very low. I think it would destroy the pump.
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I'm just being user: arsesidewards in that post
 
CrustyJeep said:
I've never heard of that happening. I mean, of course it would happen at a low enough temperature, but I think it would have to be very low. I think it would destroy the pump.
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Happens her quite a bit. Had it happen to us twice. Sometimes the defrost circuit doesn’t cut it.

I do find the idea of the defrost circuit interesting… make the pump less efficient to keep it from being efficient . :laughing:
 
rockota said:
Happens her quite a bit. Had it happen to us twice. Sometimes the defrost circuit doesn’t cut it.

I do find the idea of the defrost circuit interesting… make the pump less efficient to keep it from being efficient . :laughing:
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same as a refrigerator's defrost cycle

all of them I've taken apart had a heating element in the evap
I've heard that some have the switchgear for flipping the loop like a heat pump does but I'd bet on that being bullshit
 
CrustyJeep said:
I've never heard of that happening. I mean, of course it would happen at a low enough temperature, but I think it would have to be very low. I think it would destroy the pump.
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Can confirm this. Pretty much anytime we went below zero this winter the mini splits simply shut themselves down and wouldn’t run.
 
[486] said:
yeah ya'll got some scary shit going on during the protests

now that the world ain't watching any more, are they going about rounding up and disappearing the political dissidents?
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Maybe, it seems not, but that's only given that the financial trap of seizing so many bank accounts was so broad reaching to begin with.

The citizens of Canada did manage to at least finally get bail hearings and bail for some of the protesters. The feds have been countering by adding charges to try to prevent them from being free until their trials (that possibly will never happen).

The main thing is the newly official coalition government is trying to ram a giant internet censorship bill through so next time there will be nobody to tell on them. I think that was the main thing they learned; if people can tell on you, and tell the world, you can't get away with it without consequences. Once that is in place they will have a lot more options, and I expect them to begin exercising them. There's some other legislation brewing that has other major implications, but none of it has gone far enough to be concerned about yet.

I've been admittedly more interested in the Eurozone and China than our internal politics recently. Firstly, our own politics are deadlocked until something bigger happens, provinces have largely dropped restrictions, so the people are relaxing, thus it's no longer an environment that can breed massive or sudden change. Secondly, it doesn't matter too much if I have rights in Canada if I'm going to die face down in the mud 50 miles from Moscow. There is a lot of people that want the west in that war, and they may well get their way. I currently rate that higher on the scale of existential threats to myself.
 
CrustyJeep said:
And in both cases the air is being warmed and the air is being heated :laughing:

Heat pumps do indeed put out lower temperature air than the typical gas or electric furnace, which is not my favorite feature. But they do it over longer periods of time, so it still heats (and warms :laughing:) the house just fine.

My least favorite feature is that they're fairly complex mechanical machines. They're expensive to buy and to keep running. I'm in the process of replacing mine which is dead :frown:
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Anecdote that just occurred to me.

What feels warmer - 70 degrees and overcast or 70 degrees and sunny?

Or for the northerners… February at 30 degrees and no sun or 30 degrees and sunny?

That’s how I interpret heat pump vs gas heat.

Not that it matters
 
Scott Cee aka 2drx4 said:
Maybe, it seems not, but that's only given that the financial trap of seizing so many bank accounts was so broad reaching to begin with.

The citizens of Canada did manage to at least finally get bail hearings and bail for some of the protesters. The feds have been countering by adding charges to try to prevent them from being free until their trials (that possibly will never happen).
The main thing is the newly official coalition government is trying to ram a giant internet censorship bill through so next time there will be nobody to tell on them. I think that was the main thing they learned; if people can tell on you, and tell the world, you can't get away with it without consequences. Once that is in place they will have a lot more options, and I expect them to begin exercising them. There's some other legislation brewing that has other major implications, but none of it has gone far enough to be concerned about yet.
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Shitty, sounds a lot like our own political reality-control machine.
Scott Cee aka 2drx4 said:
Secondly, it doesn't matter too much if I have rights in Canada if I'm going to die face down in the mud 50 miles from Moscow. There is a lot of people that want the west in that war, and they may well get their way. I currently rate that higher on the scale of existential threats to myself.
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it's always smelled like avoiding a draft would be pretty easy, though I suppose with the emerging culture of dodging culturally pushed duties it could get to the point where it'd be tougher...
I mean, who would sign up to die in another stupid european/mid-east/african oil war?
 
rockota said:
Anecdote that just occurred to me.
What feels warmer - 70 degrees and overcast or 70 degrees and sunny?
Or for the northerners… February at 30 degrees and no sun or 30 degrees and sunny?
That’s how I interpret heat pump vs gas heat.
Not that it matters
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shit man, 20 deg in feb is short sleeves weather
20 deg in aug is feeling pretty cold with a jacket on

suppose a lot of it is in your head
 
[486] said:
shit man, 20 deg in feb is short sleeves weather
20 deg in aug is feeling pretty cold with a jacket on

suppose a lot of it is in your head
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Most of it is on the skin… :flipoff2:
 
[486] said:
I'll do some napkin calculations just for you

5 ton AC unit, draws 7kw, moves 60k btus worth of heat from the evap to the condenser
resistive heat is 3.41 btu per watt, so that means 17.6 Kw input to get the same 60k btu

17.6/7=2.51 so 251%

feel free to shove the long dick of thermodynamics right through any of that, I'm just a dummy with a shitty calculator
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You are not calculating efficiency, that is a compare.

A prius might get 5 times the mpg than an old pickup. That does not make the Prius 500% efficient.
 
plym49.2 said:
You are not calculating efficiency, that is a compare.

A prius might get 5 times the mpg than an old pickup. That does not make the Prius 500% efficient.
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It really is calculating efficiency, since they are transferring heat instead of creating it your house can get more energy than it consumes. He did mislabel units in the middle, its 17,600 btu input to get 60,000 btu out. And it's actually a bit better than what he came up with since 4kw of the power is used to compress the refrigerant it gets added into the heat of the house so you will get more than 60,000 btuh of heat, I think it's closer to 72,000. Plus a little bit from the blower motor, I would guess a 5 ton would use a 3/4 hp motor so that will be about 600 watts of heat. In Michigan we will install a heat pump many times when someone is on propane, and with the price of natural gas more than doubling in the last 12 months while electricity has only gone up a fraction of that it might start to make sense in that case more often. Also it seems like winters have been a little warmer the last few years so it makes the time you have to run gas heat less.
 
plym49.2 said:
You are not calculating efficiency, that is a compare.

A prius might get 5 times the mpg than an old pickup. That does not make the Prius 500% efficient.
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The Prius gets 5x the fuel economy.

A larger engine that uses more fuel can be more efficient than the little one (energy in vs energy out).

Regardless, and I agree, a heat-pump's ability to 'pull" in more heat (energy) than it uses shouldn't be expressed as efficiency. It's a different context/application.
 
u2slow said:
Regardless, and I agree, a heat-pump's ability to 'pull" in more heat (energy) than it uses shouldn't be expressed as efficiency. It's a different context/application.
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I dunno, do you really care where the heat came from?
to my simple mind, it makes more hot in the house with less 'lectric through the spinny disc on the pole
 
Tizken said:
And it's actually a bit better than what he came up with since 4kw of the power is used to compress the refrigerant it gets added into the heat of the house so you will get more than 60,000 btuh of heat, I think it's closer to 72,000.
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I just went with FLA of a 5 ton compressor I got laying around, then rounded up to the next KW to cover for fans and such, lol
 
plym49.2 said:
You are not calculating efficiency, that is a compare.

A prius might get 5 times the mpg than an old pickup. That does not make the Prius 500% efficient.
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Definitely calculating efficiency. The calculation just ignores some (most) of the energy involved. A heat pump actually moves solar energy around. If you were to takes that solar energy into account, you'd get a "normal" < 100% result. But since the solar energy is just there to use free of charge, we don't care about it.
 
If your mini split cannot heat bellow 0F you cheaped out and bought a shitty one.

I have continuously heated my shop to 60-65 degrees for 5 years with a mini split, works awesome and have NEVER had it fail to make enough heat. I did build a backup electric heat setup with a secondary thermostat but it has not been needed.

Insulation and air sealing are critical with a mini split, makeup performance will be lacking vs a huge nat gas reznor.

In my opinion if you are bellow 42 degrees latitude they are absolutely capable, so maybe 1/2 of New York state, I would expect no problems. Northern areas you may need some form of aux heat for the coldest days of the year.
 
I work for a major mini split manufacturer as a design engineer so i get to witness testing and performance of our units every day.

Most typical heat pump systems from the past 20-30 years lock out when the temperature is below 32F or so. This is to protect the system.

Newer systems are much more advanced and can provide rated heating capacity @5F and even operate to -13F. Mind you, at these low temperatures, you 36,000BTU/hr system is only producing 20,000BTU/hr or less and you should have some back up.

Take a look at this system i was a designer for. Central 3ton system with our outdoor hyper heating unit. Some interesting performance numbers there including the COP (Coefficient of Performance). COP @47F is 3.9 which mean you spend 1unit of energy to bring in 3.9 units of heat into the home. The COP will drop as outdoor temperatures drop (COP is 2.3 when the outdoor temps go down to 17F)
 
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Allen1532 said:
I work for a major mini split manufacturer as a design engineer so i get to witness testing and performance of our units every day.

Most typical heat pump systems from the past 20-30 years lock out when the temperature is below 32F or so. This is to protect the system.

Newer systems are much more advanced and can provide rated heating capacity @5F and even operate to -13F. Mind you, at these low temperatures, you 36,000BTU/hr system is only producing 20,000BTU/hr or less and you should have some back up.

Take a look at this system i was a designer for. Central 3ton system with our outdoor hyper heating unit. Some interesting performance numbers there including the COP (Coefficient of Performance). COP @47F is 3.9 which mean you spend 1unit of energy to bring in 3.9 units of heat into the home. The COP will drop as outdoor temperatures drop (COP is 2.3 when the outdoor temps go down to 17F)
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So you're saying mini split systems are better for providing AC then heat in very low temps.
 
DR. SMASHER said:
So you're saying mini split systems are better for providing AC then heat in very low temps.
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you're unclear in what you're asking, do you mean
"...ac in hot temps than heat in very low temps" or "...ac in very low temps..."
 
Not sure what you are asking but, our systems can provide cooling at lower ambient temperatures than most systems. Think kitchen or server room in the middle of winter that needs cooling. We do recommend certain systems for this application

As far as heating at lower temps, newer compressors allow for higher RPMs with the addition of injection cooling to achieve heating at the lower temps i mentioned earlier.
 
Allen1532 said:
Not sure what you are asking but, our systems can provide cooling at lower ambient temperatures than most systems. Think kitchen or server room in the middle of winter that needs cooling. We do recommend certain systems for this application

As far as heating at lower temps, newer compressors allow for higher RPMs with the addition of injection cooling to achieve heating at the lower temps i mentioned earlier.
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Stupid question. I want to add ac a room in my house independent of what my house furnace is doing. I though about getting a mini split and using it to ac that room and put the condenser in a different room of the house. I would hate to pump heat out of the house in the dead of winter.

Or could I throw the condenser in my current forces air furnace and when it’s running just have it kick the whole house fan on to cool it off.

It would only be a 10,000 btu or so system.

Is there something else that would work better?
 
that is an interesting use of a mini split, i guess you could rig something up to do this but the ducting and controlling the amount of heat you are moving from one room to another would be hard to control. To be honest, just dumping that heat outside so you have a 1:1 system would be best and easiest to control.

I would just bring outside air in which is already cold and vent the room outside. Some thermostat with two small fans working to balance the airflow should do the trick.
 
Allen1532 said:
that is an interesting use of a mini split, i guess you could rig something up to do this but the ducting and controlling the amount of heat you are moving from one room to another would be hard to control. To be honest, just dumping that heat outside so you have a 1:1 system would be best and easiest to control.

I would just bring outside air in which is already cold and vent the room outside. Some thermostat with two small fans working to balance the airflow should do the trick.
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What it is is my theater room. With a 1000w projector bulb and 3-4 people in it it gets really warm. It’s insulated and sealed to the max. It will go from 60-85 in there over the course of a movie.

I have half a basement that’s just storage where I would put the condenser. Winter time heat would go up into the above kitchen and living room. Summertime same thing but the big ac would knock it down.

The theater gets used 3x more in winter months than summer, and it would only run for a few hours at a crack. I would like it to be easy to use so my wife and kids can handle it vs me having to fuck with it also.

I know stupid first world problems.
 
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