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?
I installed a Grundfos circulator on my system in Alaska more to reduce
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.
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
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.
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:
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
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.
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.
William W. Plummer wrote:
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
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.
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.
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
As I said, it's not so simple.
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
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.
I do this several times a year. That's why the pump and motor have lasted
The baseboard radiators replaced a radiant, in-the-slab-copper system which
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
That is one of the most obnoxious, presumptuous comments I have received.
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.
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
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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