Electric bill shenanigans update

[MarkG]

I learned something important here...just passing on. Cliff notes version: if you have a hot water recirculator, make sure you really need it.

As you may remember a few months back my power bill has been running very high and I had some concern that my neighbor might be running off my power. I was looking for an explanation and then one day my power shut off when the neighbor's pool pump was turned on, leading me to think that there was some connection in the wiring between the two houses.

I didn't see any evidence of any unusual wiring, so I worked on things at the house to decrease power usage. I swapped out all of the lights (roughly 100 floods and 60 incandescent bulbs) with CFLs, which definitely made a difference and my daily usage went down 10-15%.

Then yesterday I decided to look at the hot water heater (80 gal electric) to see if that was the problem. Its listed energy use is pretty low...less than $500/yr, but I noticed it was ALWAYS running. Well...it wasn't the water heater itself it turns put but the hot water recirculator pump.

This is one of those pumps that primes the hot water lines to keep hot water ready to go. It basically cycles the water through all the lines and back to the heater continuously. Thinking about it, this would send hot water throughout the house all day and all night effectively heating the house and then reheating the water when it returns via the cold water lines to the hot water heater.

I unplugged it as a test and then rechecked the power usage this morning. Since I unplugged it, my power usage went down 60 FREAKING PERCENT. That may not hold up completely, but even if it is 40-50 percent, then it looks like I spent over $2500 last year to have this thing going and have "instant" hot water.

Lesson earned...if you have a hot water recirculator either put it on a timer or use a demand system, or eliminate it completely. The water you save by having it will be completely overshadowed by the energy cost. I'm putting a timer on mine to run in the morning only and then finding a way to eliminate it completely.




2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black

[///M3lissa]

We put one in ~2 yrs ago and didn't notice any significant changes in our bill.

Ours runs on a timer. 15 minutes every hour during "awake" hours.

I think I'll run another test just to be sure.

Thanks.

[Capt.Molecule]

We run a couple hours morning and night. Wondering the best way.

[Burgundy]

sensors in the bathrooms that would turn on the recirculator when activated, so it would only be on when u eneter the bathroom

[///M3lissa]

an hour was too long if you just happened to try for water towards the tail end of the cycle.

I never even saw a blip in the water or gas bill when it was added. Though it would have had to have been a reasonable spike to be noticeable.

[juststeve]

It's a low wattage, magnetic drive that has a 15 min interval 24 hour timer. When on, the internal thermostat maintains 85 degree water at the tap.
laing linki

[MarkG]

If there's not something messed up with it for it to be using that much power.

It has been a pretty amazing difference of just running without the pump on. Even with a lot of other power use today...TVs, lights, vacuum, laundry, dishwasher, etc more than the normal day...and nothing else changed otherwise, I'm going to be at around 60 kwhr for the last 24hr vs. 110/day avg over the last week, 129/day last month before the lights were changed, or 160/day last summer when I was getting $800/month power bills.

Thanks for the input. :-)



2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black

[MarkG]

That's one of the on-demand types.



2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black

[Father Otto T itsling]

Just curious if it would be necessary / worth while.

[ToasterDan]

Appeals to my Scottish heritage in a major way. *rofl*

[Black_Magic_Warhorse]

You might check out the size of the re-circulating pump, and see if it is oversized for your needs. Unless you have an industrial pump it's doubtful that your pump itself is the energy hog, as the culprit is the water heater itself. By turning off your pump, your water heater doesn't needed to run as much.

The pump was constantly drawing hot water out of the heater, which is almost the same as using hot water itself. Depending upon the size of your home, the size of the pump, and whether or not your hot water pipes are insulated, there is could be a significant drop in return water temperature before it is dumped back into your water heater. Which means your water heater has to work harder, since the pump was on all the time.

Putting a timer on the pump itself is a good idea, as in residential applications you really don't need it running full time. The most efficient type of of re-circulating pumps are the on-demand type. These are activated with a switch (or motion sensor) typically located at the furthest fixture from the unit, although I suppose you have multiple sensors/switches. The pump would turn on, get water to your fixture, then turn off once the hot water is detected. These cost very little to run. It would essentially be like someone turning on your faucet and running it till it got hot for you, except without wasting water. I believe TACO offers this type of demand pump as well as a couple of other mfrs.

Also, putting your water heater on a computer timer would help a lot. Unless you take late night showers, you could have your water heater timer turn off late in the evenings, kick on before you wake up, and also turn off while you are at work, but stay on the whole weekend. You could also turn down your hot water thermostat, which will save money. Unless you have several people who take showers one after the other, there's probably not a need to have it set very high.

The cheapest and easiest thing to save energy in regards to your hot water heater is to buy insulating wrap for it at the local hardware store. They have pre-made ones that just slip over your water heater. While they have increased the insulation on the more recent models, additional insulation will save money, and an 80 gallon electric heater is going to suck a lot of energy.

[eric58]

We have a recirc system with a gas heater. I put it on a timer for mornings and evenings, but I can't tell you how much I saved. In my house (Cali), the pipes run across the attic and are wrapped in the black foam insulation. Given how long it takes for M3lissa's system to cool, it might be worth a look to see if that would help. Don't forget to look at both directions.

[MarkG]

No seriously, I just knew something was wrong. The power bill has been running 5-8x as much as my previous Florida house (which was half the size) and twice what my house out West cost (which was about 4/5ths the size), so I wanted to track down the problem. If I'm right, then I've been throwing out $250-400 per month...and I'm sure I can find a better use for that.



2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black

[ToasterDan]

Carry on. ;)

[MarkG]

And that's probably why my AC has had to work overtime to undo the effects of 125 degree water running through all the pipes in the walls.

On a similar note, I was amazed how much less heat the CFLs put out than the incandescents. At any one time I was running 3 dozen or more heat lamps all over the house. Huge difference now.



2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black

[juststeve]

[juststeve]

I would hesitate turning down a water thermostat below 140-145 though. Heat above 140 has a better chance of killing any bacteria in the lines. Where as warm water has the possibility of growing it.

[tucsonjohnb]

to deliver hot water throughout the house and shuts off when it has done that. Wastes no water and only runs when you tell it to.

Timers help but you have no way to get hot water at other times other than turning on the tap and waiting for the hot water to get there.

[Shameless Behavior]

[MarkG]

Minus the timer, but it looks like that can be added on.



2008 BMW X5 4.8i Space gray/black
2007 Aston Martin V8 Vantage Supercharged Onyx Black/Black
2001 BMW M3 Imola red/black