Circulator pumps?

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We had a very cold winter here in New England and my heating system was running much of the time. So gas bills have been high, but my electric bill went up, also. I suspect the circulator pump motor might be the reason. The label on it says 1.7 amps so that is close to 200 watts or 0.2 kwh/hr or 144 kwh per month. Actually, add some because the power factor is not 1.0 but take away some because it was not running continuously. Anyway, that's about the increase I saw.
Are there more efficient circulator motor/pumps available these days? Recommendations?
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noise than any other reason. My recollection is that it consumed something like 120W but at this late date I can't recall if this was a full speed or at one of the two lower speeds. The pump was efficient enough that I never had to run it at the full speed and the house stayed warm even at sub-zero temps. Because of a peculiarity of the heating system, a hanging heater added to the garage which had no zone valve, the pump ran 24 X 7 whenever I had the boiler switched on and my electric bills weren't spectacularly high.
--
John McGaw
[Knoxville, TN, USA]
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What is your water temp set at, If its set low the pump can run 24 - 7. Baseboard heat requires apx 185 , large wall radiators 140. But going to a higher temp will help. For large wall radiators my system is set at 190. I beleive the AC motors are all comparable in efficency . Look into other areas, CFLs , Phantom loads, and doing your own energy audit with a Kill-A-Watt. Anything plugged in ex., cordless phone, TV , radio, microwave , vcr, sattelite, each apliance can easily add 1-2 $ a month, It all adds up fast.
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wrote (with possible editing):
...snip

John,
    I have a similar problem. Did you find the Grundfos was substantially quieter?
    Thanks,
--
Larry
Email to rapp at lmr dot com
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We see the same thing when there is a particularly cold month even with forced air heat from the furnace blower. December is hard to tell due to added Christmas light load. The newer furnaces claim to have lower power requirements on the blower. My present furnace (15 years old now) is better on electricity, however, I believe it's partly because the blower has higher CFMs compared to the old one, so it probably runs a bit less.
BTW, doesn't the power factor actually decrease the measured watt-hours? That's why the power company adds capacitors to correct the power factor so they don't loose money on low readings. It's been a long time since I studied these things, so I may be totally wrong here.
William W. Plummer wrote:

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I believe it is the other way because the power company must ship more power to get the same amount into the reactive (motor) load to do the actual work. It's sort of an "efficiency" thing.
A crude audit showed the circulator was 1/3 of my use, the frige was 1/3 and the rest of the house (computers, TV, clocks, electric blanket (left on), etc were the final 1/3. I get concerned when they start reading my meter in RPM. Cleaning the frige fins was hard to do and didn't seem to make any difference.

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Art Todesco wrote:

RB
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Is it worth the trouble? Even at 10 cents per KW it works out to $14.40 per month, when in use. If you drop it by 1/2 you save $7.20 per month, when in use. I assume that the circulating pump only runs on a call for heat, so warmer months will be even less. If you have connections you may be able to buy a pump for $60 for a small one, larger pumps are more yet. If you pay retail, and have someone install it, the return on investment is less yet. At $60 it probably will take 2-3 years to break even. Greg
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I don't know about circulators, but Gould has a line of more efficient motors for swimming pool pumps that really make a difference. I doubt that the efficiency of small motors (probably 0.1 HP for a circulator) warrants as much interest in improved efficiency as a 2 or 3 HP pool pump motor though.
RB
William W. Plummer wrote:

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My circulator motor says 1.7 amps. At 115 vac, that is 200 watts. 200 / 746 is a little more than 1/4 HP. However, I don't know if the motor is fully loaded by loop of baseboard radiators, all on one floor. Another poster pointed out that using higher temperature water will deliver the required heat in a shorter time, minimizing the time the circulator is running.

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Which would raise the amount of gas or oil one uses to heat the water. Certainly would cost more than the $14 a month it costs to run the pump! Greg
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But for most of us electricity is double the cost of gas per btu extracted so raising water temp is overall cheaper than running a pump
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I agree. The boiler will only be on during the time that the circulater is running, i.e., when a zone thermostat is calling for heat. So shortening the time the thermostat calls for heat shortens the circulator time and the burner time. It's a super win to use higher water temp. Also, note that heat flow (calories per hour) is proportional to the temperature difference (water to room), so that's another reason to use high temp water.
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in message

So, by raising the water temp, you reduce the heat flow into the water from the flame?
Bob
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by raising water temp your thermostat- temp will reach and maintain desired temp longer without boiler or pump running, with low water temp a pump can just run continously refiring off the aquastat. So with longer boiler operation water reaches a higher temp.
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Good points all, but....
It's not so simple.
First, adjusting the aquastat to a higher temperature changes the high limit, which is not the always the same as raising the actual temperature of the water. Most boilers, during all but the coldest weather, will not get the water temperature up to the high limit setting very often. Remember, the burner only fires when a zone is calling for heat (and the water temp is below high limit setting). Since most boilers are selected to have sufficient capacity to heat the house even when temperature is at the design low, when the outside temp is warmer, the house reaches the thermostat setting and shuts down the burner before the water temp reaches high limit. The only time my boiler hits high limit is first thing in the morning in very cold weather when the system is raising the house temp from the night setback to normal temperature.
It takes the same number of btu's delivered to the radiators to maintain your house at temperature whether the water is at 140 or 190. It's true that at a lower water temperature, the circ will have to run longer to deliver those btu's, and several have pointed out correctly that this costs real money. But running the water temperature higher increases the standby losses up the stack, which also costs real money. If you have an automatic vent damper, this helps this somewhat. Standby losses are also increased when the standby time is increased. Running higher water temp means more and longer standby periods compared to lower water temp. Comparing the cost of electricity to gas is irrelevant; you are not comparing electric heat to gas heat. In this case, gas is always heating the water, electricity is pushing it around. You save electricity by running the circ less, but you pay it back by making up for the standby losses with gas. Which factor wins depends on average temperature, boiler efficiency, presence of vent damper, how well the boiler is matched to the house, and on and on.
While running at lower water temp means the circ will run more, this actually tends to deliver more even and comfortable heat, with fewer cold drafts during the off time of the circulator. Yes it costs more to run the circ longer, but some are willing to pay for more even heat and the comfort. Again, this is offset also by the reduced standby losses.
As I said, it's not so simple.
Paul Franklin
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Yea paul but standby loss on any boiler is minimal compared to radiator loss , so get an Auto vent as most New systems have Even so a higher effeciency system is best
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Well, there's not a lot you can do about it. Except maybe a couple drops of Bell and Gossett approved oil in the oil cups.
If I was a wise acre, I'd suggest that you could save a lot of money by disconnecting the pump, but I won't go there.
If it really bothers you, maybe your heating guy can turn up the boiler temp a couple degrees, so the pump doesn't run as often. But that would increase the risk of burns on the radiators, and would likely cost more than the electric savings.
I'd reccomend that you find something more signifigant to worry about. That's not very high on my list of things to concern me.
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Christopher A. Young
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so long.

had gotten very leaky. I understand it was standard to set the temp fairly low on those systems. I will have it checked the next time I have it serviced.

First, I will worry about whatever I want to worry about and do not need your OK. Next, FYI I am out of work and money is very tight so being frugal is in order.

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There is an aquastat on your boiler , either on it or under the front cover, it will have a dial or screw adjustment and temp numbers on the wheel. Just read it and set it to 170 or 180. unless its set real low your savings will be mimimal and other things should be looked into for saving electricity. An 9$ pack of 4 - 13 watt compact flourescent that equal 60 watt incandesant at HD or Menards will pay for itself in in 2 weeks at ,125 KWH run 24 x 7 . Thats a good investment. I wouldnt disconnect it as Wise Acre Stormin suggests it could be . Only Stormin worries about burns on a radiator he probably uses them as chairs to warm his hemroids.Stormys Roid warmers. And yes everything you change will help electric bills , but why pay a service call for it. Putting my tv vcr sattelite , dvd , stereo, on a switch and turning it off at night saved me 4 $ a month . I removed 4 cordless phones and save another 6
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