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shutting off my heater daily

We recently moved into our home and it is our first experience with oil heat (and an oil burner). We rarely use our heat (hot water base board) as we burn wood for most of our heat. The only time we use our heater is to heat up water for a daily shower and occasionally to heat the house if we are low on wood.

My question is this. Is there any inherent danger to our system if we frequently shut off our heater (using the red emergency shut-off switch on our main floor of our house)whenever we are not in need of it?

Basically, I have been turning the heater on when I take a shower, and then shutting it off when I get out. I repeat this process daily. It just doesn't seem to make sense to us if we are constantly heating up a tank of water (it is a small tank--maybe 5-10 gallons) all day just so we can use 5 minutes worth of hot water.

One technician told us that there is a danger of the gaskets suffering damage due to the constant expansion and contraction caused by the temperature changes. Not sure if he was being overprotective or not....

Any suggestions/advice would be greatly appreciated. Thanks.

Re: shutting off my heater daily

Sounds to me like you have a boiler as you have baseboard heat. Does your hot water heater run off of your boiler or is it seperate? Do you have an oil fired hot water heater? If it's seperate shutting your heater off when you get out of the shower won't do any good. At any rate I wouldn't know about damaging your the Gaskets but why don't you just shut it off at the Thermostat, or turn it down to say 60 degrees. Good Luck!!!:)

Re: shutting off my heater daily

Thanks for your reply. You kind of lost me with your questions (I am not good with how things work). All I know is that the oil tank (indoors) runs into our oil burner. Attached to that oil burner is a small holding tank (about 5 gallons). As I understand it, this is all the water that gets heated up for both our baseboards as well as our sink/shower water (there are no other vessels to hold water in our basement). When I turn off the emergency switch, we get no hot water anywhere, and no heat anywhere. When it is on, we get it all.

Sorry if I am a bit clueless, but this is not my forte!

Thanks again

Re: shutting off my heater daily


Yes, you have a boiler there with what is known as a "sideshot" tank for a few gallon of hot water for showers, etc.---the sideshot is usually run off a copper coil that is embedded inside the boiler as a heat exchanger and is separate from the boiler water.

These types of boilers are set up to provide house heat AND the 5 gallons of domestic water---thus, there is a "triple aquastat" (boiler water temp controller) that turns on the boiler every time the temp of the water in the "sideshot" falls below 140 degrees.

Thus, even when you never need to heat the house, the boiler still comes on to heat the sideshot---this can be wasteful of fuel, & a few gallons of hot water using this method is usually not adequate for a family of 4 or more that needs much more HW for clothes washing, showers, dishwashing, etc.

But if you have 1 or 2 in the family it may be the only compromise, given the equipment---I think you will probably use the boiler for more house heat as the weather gets colder, depending on your location---I don't see any major problem in turning the boiler's main switch off if you want to save some fuel---later on, if you have freezing temperatures, you run the risk of having the heating pipes freeze, especially in remote parts of the house if you rely solely on the wood stove.

You should be aware that the "standard" way of using a boiler to obtain domestic hot water AND hot water to heat the house is to install a 30 gallon or 40 gallon INDIRECT HOT WATER HEATER---these are highly insulated tanks that are set up something like the "sideshot", but with a "zone valve" or "zone circulator" that keeps the 30-40 gallons at approx. 140 degrees for many hours---this setup is more efficient in its use of fuel and you'll never run out of domestic hot water---typical cost is $700-$1k for the IHWH plus $500 for labor.

The type of boiler you have is not designed for an "extended shutdown", lasting several months---it is in those instances that corrosion, and combustion chamber seal leakage often occurs that would considerably shorten the life of the boiler.

Re: shutting off my heater daily

Thanks so much!

What you said rings true. My wife has already mentioned looking into a larger water heater. In the meantime, we will likely shut off our system regularly--but not for more than a few days in a row (we have been cautioned about the corrosion and seal leakage.

Thanks for your help.

Re: shutting off my heater daily

Nashua Tech comes through again, is there anything you don't know, LOL, you are the man!!!! Seriously!!!!! ;)

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