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Is it safe to shut off furnace during summer?

techheattechheat Member Posts: 117
The Boiler will scale up and will require extensive cleaning in the Fall,the gaskets will also probably leak creating more problems down the road.If you have a triple aquastat you can turn the Lo setting all the way down when the heating season is over this will keep the boiler warm{not hot} and prevent the problems mentioned.BTW if you have electric HW you should consider a indirect or aquabooster,much cheaper{by far} to operate than an electric water heater

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  • DanielleDanielle Member Posts: 6
    Is it safe to shut off furnace during the summer?

    We have a new (approx. 1 year old) Burnham furnace that heats our house via forced hot water in baseboards. It is fueled by oil.

    Separately we have an electric hot water tank that heats our domestic (at least that is what I was told it is called, I am new to all of this) hot water.

    In the summer the furnace will kick on now and then to heat the water in there because it thinks it has to always keep it at a certain tempurature, despite it really not having to do so.

    Is it safe to shut it down during the summer? I don't want to waste oil and listen to it kick on (it is right below the living room so it is certainly noticeable when it kicks on) if I don't HAVE to.

    I was told yes, but to run it once for an hour every 2 weeks... is this true?

    Thank you.
  • DanielleDanielle Member Posts: 6

    I have no idea what most of that meant, but thank you for the response.

    (clueless new first time homeowner)
  • JeffDJeffD Member Posts: 41
    Shutting down


    Don't shut it down during the summer. As the boiler cools off, the sections of the boiler won't be held as tightly together, so it could start to leak. Any gaskets could start to slowly leak as well. Also the cold boiler surfaces will condense moisture from the warm moist summer air. This will cause rusting. You can lower the temperature on the aquastat to 140*, but leaving it on all summer won't use much fuel oil. Consider it money well spent to protect your investment.
  • DanielleDanielle Member Posts: 6
    Thank You...


    Thanks for simplifying the explanation. 140 - thanks for that info as well.

    Have a wonderful weekend :)
  • sootmonkeysootmonkey Member Posts: 158

    yeah, shut the boiler off...jmo...before you do though....take a couple of adjustable wrenches and tighten up your circulator gaskets...also, if you have a 'dummy plate", where the coil would go, tighten those bolts up too....maybe just snug up the packing nuts on the gate valves....again jmo....what my peers said, in their posts about indirect h2o heaters, is spot on....also...if no hot h2o from boiler, set low limit at 120 during heat season, will save some $$......i typed this thinking that you have an oil fired boiler...if this is true, just shut the switch off, and tighten the above mentioned bolts/nuts...if your unit is gas fired, ask your gas guy about proper shut down...if your gaskets leak then have them replaced....YOUR BOILER SHOULD NOT EXPERENCE ANY DAMAGE BY SHUTTING IT OFF IN THE SUMMER MONTHS...JMO..
  • sootmonkeysootmonkey Member Posts: 158

    sorry guys about the caps....i just reread my post and the caps do not come across as i thought they would...3 days no camal smokey...lots of attitude....cheers
  • J.C.A.J.C.A. Member Posts: 2,981

    Trust the guys who said to keep it warm. DON'T shut it off!

    I wholeheartedly agree with all about getting an indirect fired water heater. The upfront cost is more, but in the longterm, this will save you money and service problems.Lifetime warranties and keeping the chimney working all year mean less service overall.

    Sootmonkey, Have you been servicing oil for a while? If you have, you would KNOW that cold starting is/has been dubbed nonsense. The service will cost more than the fuel used during off season.(YES EVEN WITH FUEL PRICES AS HIGH AS THEY ARE!! caps not unintentional) A boiler temperature above 115° is preferred, higher than condensing temps for the boiler.Apparently NOT JMHO. Chris
  • gfegfe Member Posts: 14

    I"ve got a gas fired two pipe steam system...what should I do during the summer? thanks
  • sootmonkeysootmonkey Member Posts: 158

    Cris..I have much respect for you and your work. You are very obouslly above average in your field. I follow this site and OTT way to closelly. Yeah I know that I cant spell. There are some disadvantages of cold start. Are most steam boilers cold start?... No,I don't think that cold start is the best way to go in a hot water oil boiler. The question was something to the effect of shuting the boiler down completely for the summer. I say yes, shut the boiler off for the summer, just tighten the external gaskets. Cris, I have a LOT of respect for your opinion. As to my experence...well, you can ask me any question you want...judge me by my replyes...not my spelling. again with respect Keith
  • t. tekushant. tekushan Member Posts: 141
    something else to keep me up at night

    Great. Something else to think about. I know this was a hot water question, but its brought up something on steam boilers.

    Commercial steamers are usually kept warm. I've seen a couple 'o residential steamers kept warm.

    Is keeping the boiler warm applicable to the average sectional cast iron steam boiler? The reason I ask is that one of the boilers in this building is an undersized steam W-M that's been overfired to meet the load. Its not my building and the boilers are in a separate boiler plant area and the cheapskate landlord won't put in the properly sized boiler (I generally talk to the boiler room walls; they are more receptive than the landlord), but still, I wince every time that poor thing starts from cold. I feel its thermal shock pain.
    Should an aquastat be used?

    Up until now, I've kind of hoped this little W-M EG45 would fail, forcing a properly sized boiler replacement. When I came on board here, it had NEVER been blown down, and the auto-feeder added water every 45 minutes of operation due to return leaks. I repaired all that and descaled, cleaned, etc. I would have thought that 10 of 18 years of this horrible abuse and 18 years of over firing would have killed it by now. I have to hand it to W-M. That boiler is still humming along. And since its bound and determined to live on, I just wonder if its not too late to add this feature.

  • JimJim Member Posts: 13

    I also have a pretty new steam boiler with a tankless coil that feeds the water to my separate gas-fired hot water tank. The hotwater heater by itself makes plenty of hotwater for my wife and me. I also wondered about turning the boiler off during the summer. The tankless is a nice back-up and probably decreases my gas bill since the water heater gets already hot water but I was also told to keep the boiler on during the summer. This was told to me by the both the people who service it and sell me oil (a little suspiciois) but was confirmed by a boiler pro who I trust. But what do people do who do not have the tankless option that causes the boiler to come on when the thermostat does not call for heat. That is, in the summer, wouldn't the boiler stay off the entire summer anyway as long as the thermostat doesn't call for heat if there is no tankless component? Are all of these people ruining their boilers?
  • roncoronco Member Posts: 1
    summer shut down

    I recomend the boiler be cleaned prior to shut down. If anything leaks then I would address the leaks. Tightening gaskets and bolts with out reason is looking for trouble.
  • TimcoTimco Member Posts: 2,829
    same question

    I have a nat gas HW boiler for the heat...newer Teledyne-Larrs. Should the t-stats just be turned down, or the boiler shut off for the summer? Bangs & knocks alot on cold startup in the fall.

    Working on steam and hot-water systems isn't rocket's actually much harder.
  • WPH2205WPH2205 Member Posts: 52

    Danielle, don't shut that boiler off. I have found that leaving it on, just turn down the water temp. works well. You won't have any leaking gaskets, and the boiler is much easier to clean in the fall.
  • thfurnitureguythfurnitureguy Member Posts: 388

    Burnham boiler Mfg. says to "fill the boiler to the top of the water column and leave it that way. Prior to start up next Fall drain to the proper level". shutting off the manual oil valve (fuel), and spraying the inside burning surface with light oil to prevent rust are also recomended. THIS IS FOR A STEAM, OIL FIRED,BOILER WITH NO WATER HEATING COIL. Get online and ask the Mfg for your boiler shutdown instructions. Best luck T.
  • jeffjeff Member Posts: 545
    I think you guys have all missed the point

    According to the lady, this is a forced hot water boiler. No need whatever to keep it firing in the summer. You certainly won't corrode anything in a system filled with water and unless I am mistaken, the burnham is a push nipple boiler, shouldn't leak in anycase. I do agree that a hot water maker off the boiler is certainly a much better idea than the electric water heater. More hot water at less price and then there is no need for disagrement 'cause the boiler will fire all sumer long for hot water. And always have an oilfired system serviced everyfall, or better yet, late summer.
  • WPH2205WPH2205 Member Posts: 52

    Jeff, I haven't missed the point at all. It makes no difference whether it's steam or water. It's better for the boiler and easier to service if it's left on.
  • Taino871Taino871 Member Posts: 1
    IT IS SAFE TO Shut down your Heating system

    I am in the heating Bizz for years, Oil,Gas,Electric. Yes it is safe to shut down the units. I agree with tightening coil gaskets. But that is all. Shut them down have them serviced by a Service Company Not a buddy that has " AN Idea" how to do it. at the price of fuels today it is really wasteful to heat these units. 23 years in the heating bizz,
  • billtwocasebilltwocase Member Posts: 2,385
    only because the price of fuel

    will I say shut it down for the summer. I would personally turn the Lo limit down as low as it will go, about 100 degrees. All stays as it should, and boiler lasts longer, but if you are leaning toward shutting it down, have it thoroughly cleaned and serviced so it won't be plugged when to turn it back on in the fall. This I have learned after 30 years in the biz
  • PriceOfOilPriceOfOil Member Posts: 1
    How about shutting the boiler down for 23 hours every day?

    I just installed a woodstove in the living room on the first floor of our small house.

    I have an unlimited supply of firewood on my land and a wife that loves to split wood

    None of my four zones are firing because the woodstove is keeping the temps higher than the set temp on all four thermostats.

    I have a tankless coil inside my Utica Starfire II oil boiler in the basement. I have no water storage tank.

    Here is my question: Is it okay to shut the boiler off for 23 hours each and every day - since neither my wife nor I is home and we are doing the dinner dishes at 9pm followed by showers for the both of us.

    Is there any danger to turning the boiler off for 23 hours each day? It is winter here in Maine and it is 15 degrees outside. The basement temp is about a steady 48 degrees when the boiler is turned off.

    Thanks for your "experienced" answers!
  • Al RoethlisbergerAl Roethlisberger Member Posts: 194
    What about controls that support WWSD?

    I believe that some of the more advanced residential boiler control systems support Warm Weather Shut Down(WWSD) modes that essentially shut the boiler down when the outdoor sensor reaches its WWSD set-point.

    But one of the functions during the WWSD is that the control still regularly(daily?  I forget) excercises all valves and pumps, and may even fire the boiler briefly(I'd have to check on that, I don't recall 100%).

    But the point being is that there are clearly controls designed for supporting boilers being "shut down" during the non-heating season which in warmer climates can be the far more significant part of the year.

    I don't doubt that running the boilers constantly in some low temp steady-state is the ideal(as with any system) but I wonder if this may be cost prohibitive given fuel costs for those in warmer climates?

    Just a DIY'er trying to learn, and improve and maintain his converted ca 1929 overhead gravity hot water system since there is no one local that can.
  • Jean-David BeyerJean-David Beyer Member Posts: 2,534

    I have a W-M ultra 3 that has warm weather shutdown. I am not sure that it is very important for a boiler like this. The boiler is cold start, so if nothing calls for heat, it would not run anyway. Mine is set for 70F outside (the factory default setitng), and I have not bothered to change it. I have to leave the boiler on all the time anyway because it provides the heat for my indirect hot water heater, but it fires for this in warm weather only when the indirect calls for heat.

    The controller will exercise the circulators for 10 seconds every 72 hours of inactivity. It would not fire the boiler unless its temperature got below 40F (or something like that).
  • meplumbermeplumber Member Posts: 678
    I have been shutting mine down every summer for years.

    You all know my opinions of cold start boilers, but I have been shutting mine down every summer for years.  In the fall, I start it up and let it run for a day or so and then clean it.  The old girl is 15 years old and still runs fine.  On occassion I will have a circ leak, but that is it.

    I shut boilers down for the winter (seasonal customer base) and fire them back up in the spring.  Run them for a few days and then go back to clean them.  Got some out there close to 30 years old. 

    Just my $.02 worth. 

    Good Luck.
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