Hot water boiler

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

cmonSTART

Minister of Fire
Hearth Supporter
So, this evil boiler we have is an object of contempt for me lately. Our oil tank is almost empty and the thought of spending 600 to 800 dollars to fill it just isn't going to fly right now. How do I keep this thing as efficient as possible?

We had it cleaned and serviced last year and the guy said it was pretty dirty. I would like to take some time to clean it but want to know what I should be looking for ahead of time. What's in there?

Also, it periodically runs to maintain a supply of hot water right. Is there any way to make it run ONLY when there is a demand for it? It heats the water up almost instantly when it runs, so there wouldn't be any lag time.
 
Sounds like you have a tankless coil installed for your DHW. These are not the best available technology for water heating, not by a long shot. They're great if you want to be able to fill up a swimming pool, but their overall energy efficiency is pretty poor (25% is a typical number I hear).

I guess the answer is going to depend on how much you use it for space heating. If it runs much in the winter, leave it alone, but install an electric storage heater next to it. In the summer, shut down the boiler and use the electric. If you have successfully weaned the rest of the house off of oil and the boiler is used mainly for DHW, use the electric heater, or consider an "indirect" heater to only run the boiler 1-2 times a day.

If you want something cheap and effective, shut the boiler off completely during the day (at the emergency switch) and turn it on about 30 minutes before you need it. It will recover quickly and still give you all the hot water you need. If you want to get a little more sophisticated, you can put a timer on the boiler to kick it on in the morning for showers ant the evening for dishwashing or whatever. Even a windup timer that shuts it off after an hour will probably pay for itself in about a month at current oil prices.

Ironically, it is probably the low temp short cycling for DHW that is sooting up the boiler. Shut it down and it won't get dirty!

Chris
 
I'm in the same boat with a DHW coil in an oil fired boiler. I've been heating the house well this past winter with 2 NC-13s so I don't plan to use the hydronic baseboards anymore. If I begin switching it off when there is no demand for hot water, how long does it have to be off to make up for the oil that's used to bring everything back up from room temperature?
 
It will not use any more oil to come back up to temp than if you left it on. As soon as it cools off a little bit, it is saving money. Oil burners run better flat out than cycling anyway...

Chris
 
Status
Not open for further replies.