monitoring power usage

[Bill Arden]

I started with a clamp on amp meter, then got a kill-o-watt meter.

The small clamp on unit that chris8796 suggested could be installed on a feeder circuit. There are other unit like that.

The main reason for monitoring power is to properly prioritize improvements and to discover problems.

Some examples of maintenance issues:
1. Refrigerators draw more power when the coils get dirty.
2. Air source Heat pumps shut down when the outside gets dirty.
3. Gas water heaters use more gas when they are filled with sludge.

My local power utility has a neat web site that shows how much power I use each day along with the outdoor temperature. Since I have two meters it shows heating and regular power separately.

 

[Billy_Bob]

Look for a manufacture date on the refrigerator. If it is more than 7 years old, a new model will save electricity.

For a heat pump, the new Carrier Infinity says 19 SEER rating...
http://www.residential.carrier.com/products/acheatpumps/heatpumps/infinity.shtml

And if replacing a heat pump with a new high efficiency unit, also replace the inside air handler / coils as these work hand in hand to provide the most efficiency. They do all sorts of trickery with the electricity and motors to gain the highest efficiency.

If you can get natural gas, the new furnaces are so efficient, they use PVC for an exhaust pipe instead of the metal chimney!

 

[Sponsor]

 

[atuel]

So no natural gas at the house now, though I've wondered about this since I prefer to cook on a gas stove

Any idea which of the various types of home heat is the most efficient these days? Gas? Electric? HeatPump?


I did some more investigating including staying home today to monitor it over a day where it's sort of cold outside. The downstairs unit ran all day after I turned it back on. It wasnt even cold inside.

This two zone thing I have has a LED on it to indicate when emergency heat kicks in and it comes on right away. I also found the manual for this tucked up in the closet its actually does have electric controlled dampers that I dont think are opening reliably. At one point, it was running an I had next to no air flow out of any of the vents. I've never understood why this was a two zone anyway since both zones are on the first floor with the upstairs having its own heat pump.

I'll have to crawl into the crawl space and check on the dampers... probably just lock them open and kill the crappy 2 zone thing. The manual says it doesnt even listen to the thermostat and will only allow 1 change every 15 minutes and it prevents me from using the unit with the fan only on to help spread heat from my wood/coal burning stove.

 

[CodeOne]

I'm on the Wake/Johnston county line. Any way to tell if the heat strips are coming on? I've actually had my upstairs heat pump turned completley off for at least the last few weeks. My downstairs one was turned on, though was set to 68.

The system is fairly old and shows it... wouldnt be suprised if it was nearly original to the house from the mid 80s. The exterior piece says Carrier Tech 2000 SS on the top of it and best guess I can find is its cerca 1993. I have two of these... Downstairs unit is connected to a Carrier 2 zone WeatherMaker as well.

It could be the reversing valves are sticking which would cause your hp to not come on and only the strips to come on prematurely. Also HP's do not work well past 32 deg. and the strips would come on.
You could turn you unit to where they would be calling for heat and go out and watch to see if the compressors come on and stay on. Also on you thermostat there should be an indicator if the emergency strips come on. Each unit is a little different.
Still suggest you have someone check/service them to be sure. Be sure and get a repetuable company.

 

[atuel]

It could be the reversing valves are sticking which would cause your hp to not come on and only the strips to come on prematurely. Also HP's do not work well past 32 deg. and the strips would come on.
You could turn you unit to where they would be calling for heat and go out and watch to see if the compressors come on and stay on. Also on you thermostat there should be an indicator if the emergency strips come on. Each unit is a little different.
Still suggest you have someone check/service them to be sure. Be sure and get a repetuable company.

Yeah, I found the emergency indicator... I have this stupid 2-zone deal that is actually controlling it. It says the emergency strips come on all the time right away (its 50 degrees outside today when I checked this). The compressors are also running. And since I posted before, I'm pretty sure the air dampers that go with the 2-zone thing are not opening properly.

Since this 2-zone thing is not needed for this house, I'm just going to bypass it and go back to a single zone.


BTW, I'd still want to be able to monitor so I can cut this off quicker next time rather than spend a couple months paying high bills like this.

 

[CodeOne]

Yeah, I found the emergency indicator... I have this stupid 2-zone deal that is actually controlling it. It says the emergency strips come on all the time right away (its 50 degrees outside today when I checked this). The compressors are also running. And since I posted before, I'm pretty sure the air dampers that go with the 2-zone thing are not opening properly.

Sounds like you may have solved you major cause of your high bills. At least if you can get this corrected you should see a major drop in your winter bill. Hope so. Take care.
Mel

 

[atuel]

Yeah... now I just have to crawl under my house to open the dampers permanently.


I'd still want to be able to monitor. I'm guessing no one has a solution for less than the $2000 that can monitor circuit by circuit. This is the second time it would have saved me big time... lost a fridge full of food cause my fridge start relay died. Seeing the drop in energy usage would have alerted me to go check it out.

 

[CodeOne]

You still may have a relay sticking in your unit. I'm not sure the dampers closed would cause the strips to come on like that all the time.

 

[Billy_Bob]

If you have a woodstove, you may be able to use that and turn off the heat pump for 24 hours - and read your electric meter. Then turn on heat pump and read your electric meter again.

So far as the cost, electric bills are very complex as to charges. Probably the easiest thing to do would be to look at your total kilowatt hours used each month and divide by the number of days on the bill to come up with a daily usage.

Then experiment around with turning off what you can for 24 hour periods and see how much this reduces your use.

You do have a meter, just learn how to read it and experiment with one thing at a time.

How to read an electric meter...
http://pacificpower.apogee.net/res/refrmtr.asp

More on electric meter reading...
http://www.google.com/search?hl=en&q=electric+meter+reading&aq=f&oq=

Kilowatt hour explained...
http://en.wikipedia.org/wiki/Watt-hour

Watt explained...
http://en.wikipedia.org/wiki/Watt

 

[Alternety]

For refrigerators you can buy temperature alarms.

I just read through this post for the first time. I believe you have been told several times what you problem is likely to be. You confirmed this with the indicators on the thermostat.

Your heat pump is malfunctioning. You do not need a current monitor for the biggest probable load. Look at the rating on the fans and compressor of the heat pump. Look at the KW rating of the backup (emergency) heating coils.

When you thermostat says the heat pump is running (and you can hear the compressor and the indoor and outdoor fans, this is the power you are using. Whenever the emergency heat light is on you are ALSO using that amount of power. Together they should dwarf any other load in the house except maybe an electric range together with an electric water heater. If the water heater was running all the time you would have opened the TPR and you would see water/steam running out all the time.You would have unbearably hot water and steam in the hot water faucets. Not a likely scenario. You would notice leaving on the range (or electric clothes dryer).

It is unlikely to be the dampers. If the resistance heat in the pump is on, the pump electronics thinks it is not producing enough heat (or maybe a frozen coil). If the dampers area problem, I would expect the heat to build up in the air handler and not keep the resistive heat on. It could be a sensor or electronics problem; but given the age I suspect the heat pump is just broke.

Get a heat pump person in.