Water Heater Timer? Gas or Electric? Any recommendations?

Discussion in 'Water Heater Forum, Tanks' started by watergirl123, Jan 21, 2011.

  1. watergirl123

    watergirl123 New Member

    Messages:
    2
    Location:
    Redding, CA
  2. Dana

    Dana In the trades

    Messages:
    2,784
    Location:
    01609
    With electric tanks, the timers are essentially useless- the temps don't fall far enough over 8-10 hours to reduce the average heat loss by even a percent or two.

    With gas heaters (which are inherently lossier due to the necessary insultion gaps and convection through the center tank heat exchanger) it's maybe a bit more, but "...a worthwhile investment..." probably not, in most cases. (It might be with propane-fired tanks though, due the high cost of the fuel.)

    What IS a worthwhile investment is insulating the near-tank plumbing (withing 6' of the tank) to at least R4 with closed-cell foam pipe insulation (including the cold feed an the temperature & pressure outledt plumbing), as well as any accessible hot water distribution plumbing. The cheezy 3/8" wall stuff sold at box stores is better than nothing (~ R2) , but in most instances going with 5/8"-3/4" wall goods (online, or from plumbing supply houses, or Grainger). See:


    http://www.leaningpinesoftware.com/hot_water_pipes.shtml


    http://www.leaningpinesoftware.com/hot_water_heater_vacation.shtml

    http://www.leaningpinesoftware.com/hot_water_pipes_pipe_cooling.shtml

    Sometimes the better solution is the lowest-tech.
  3. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,251
    Location:
    Cave Creek, Arizona
    Unless the timer causes the tank to become completely cold and keeps it that way for an extended time, the timer does NOTHING to save gas, because the burner just has to run for a single longer time to reheat the tank instead of operating for short periods several times. IF it lets it get cold, and you don't mind having NO hot water, then it will save gas, because it just has to heat a single tank of water, instead of reheating all the water you used, (which could have been MORE than the 40 or 50 gallons the tank holds), while the timer kept it off. And this applies to both electric and gas models.
  4. ballvalve

    ballvalve General Engineering Contractor

    Messages:
    3,261
    Location:
    northfork, california
    A good place to store all your old jackets is on top of a electric water heater. Long underwear makes great pipe wrap also.
  5. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,251
    Location:
    Cave Creek, Arizona
    If you expect the jackets to get "warm" forget it. The new heater's insulation does not give off much heat.
  6. ballvalve

    ballvalve General Engineering Contractor

    Messages:
    3,261
    Location:
    northfork, california
    I can tell you that under my jacket pile, you could likely poach an egg. Those new heaters leak heat, but the case does not feel warm because its constantly being shed to daylight. The T&P is like a heat sink when left exposed to daylight also.
  7. jeffreyd

    jeffreyd New Member

    Messages:
    2
    Location:
    California
    Gas Water Heater Timers can be useless in certain applications. For less than $150.00 investment it is certainly a good idea to try one out. You will certainly regain your investment. The amount of time will vary. See www.gaswaterheatertimer.com or waterheatertimer.org for more info.
  8. LLigetfa

    LLigetfa DIYer, not in the trades

    Messages:
    3,826
    Location:
    NW Ontario, Canada
    Only if there is time-of-use billing, can I see any real benefit. Defer consumption to the off-peak billing rate.
  9. jeffreyd

    jeffreyd New Member

    Messages:
    2
    Location:
    California
    Gas Water Heater Timer

    Timers have been installed on electric water heaters for decades. They do work in most cases. There is a gas water heater timer available. See www.gaswaterheatertimer.com
  10. energyman1

    energyman1 In the Trades

    Messages:
    3
    Location:
    California
    See the website www.gaswaterheatertimer.com and open the PDF. This shows testing done by Bradford White which shows energy savings up to 36% by using a gas water heater timer. The timer on this website is a great product!
  11. JerryR

    JerryR Member

    Messages:
    231
    Location:
    Florida
    Sure they "work", but are they cost effective is the important question.

    One study in Florida estimated savings of 21 cents per month.

    There is no energy credit that I know of that applies to timers on water heaters. That tells you something.

    If you live in a warm climate then heat recovery units on your air conditioner are great. I turned my water heater circuit breaker off 9 months a year and never ran out of hot water. It recovered the heat removed from the home and used it to heat the water in the tank. It also increased the efficiency of the central air by 5%.

    Jerry
    Last edited: Nov 12, 2012
  12. LLigetfa

    LLigetfa DIYer, not in the trades

    Messages:
    3,826
    Location:
    NW Ontario, Canada
    And that's in a Southern state where it costs more to cool than it does to heat. In many other parts of the World, the small amount of standby heat loss is not really lost, it is heating the house.
  13. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,251
    Location:
    Cave Creek, Arizona
    Interesting that BradfordWhite would endorse that timer, because it will NOT work with their thermostats. Again, however, if the gas burner turns back on before the tank gets cold, then you saved NOTHING, because the burner will have to reheat the water you used, regardless of whether it is one long burn, or several shorter ones. It is only when the tank goes cold and you continue using the cold water that you save money, because when the burner comes on it only has to heat the water in the tank, NOT all the water you used after the hot water ran out.
  14. Dana

    Dana In the trades

    Messages:
    2,784
    Location:
    01609
    It's not exactly nothing- the standby losses drop with tank temp even when you're not using the tepid water in the tank. On lossy atmosheric drafted gas HW heaters automatic setback might have some advantage- the temp would drop more than 10F overnight, for a lower average standby loss. The less lossy the water heater, the less you'd get out of a setback strategy.

    The only time the savings outlined in that PDF hit 36% was in the very low volume use profile (not surprisingly.) As a percentage of the total fuel use the standby loss dominates when the use volumes are low. But 36% of a tiny number may never have an economic rationale, since the savings are probably less than the 7% savings indicated in the "typical" water use profile. But you'd get more than a 7% savings by simply dropping the storage temp from 130F to 125F to lower the standby loss.
Similar Threads: Water Heater
Forum Title Date
Water Heater Forum, Tanks Noob question about hot water heater Jul 13, 2014
Water Heater Forum, Tanks Water heater size with and without tempering valve Jul 12, 2014
Water Heater Forum, Tanks Venting options for gas water heater Jul 6, 2014
Water Heater Forum, Tanks Water Heater drain valve failure Jun 26, 2014
Water Heater Forum, Tanks water heater over temp (T & P ) valve piping question Jun 25, 2014

Share This Page