Buderus H20 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.
Status
Not open for further replies.

Tom Pencil

Member
Oct 30, 2008
159
Tipp City, Ohio
Purchased a New Buderus water boiler in 2002 that runs on fuel oil. It runs great and very efficient. Before we bought our pellet stove in 2004, It would eat about 920 - 950 gallons/year. Now it only drinks about 320 - 350 gallons/year. Every year we have had general fall tune up done on it and they always say that it is one of the cleanest boilers they service. They clean what little ash/soot is in it and just replace the oil filter and nozzle.
Started it up the other day so I would have heat while my pellet stove was shutting down for a good cleaning and ran just fine.

So question is should I continue to have this service done every year? Or could I go every other year or even every third year?
 
I'd skip a year or two with the lower usage.
 
I would keep to annual cleanings. My assumption is that you are operating the boiler as a cold start device I.E. it only runs when there is heating demand. I think the Buderus is a multi pass heat exchanger design to gain effiiciency. The combination of a cold start and a long heat exchanger path can introduce build up that hardens up over the summer. I tried to go to every other year cleanings with and older Crown boiler that is run as a cold start and it almost plugged solid the second winter. I was burning about 300 gallons per year when this occured. What I have resorted to is buying a cleaning brush and cleaning the heat exchanger every other year without having a tune up. When I pulled my tank filter recently, there wasnt much sediment build up and the flame looks reasonable so I expect I will go twice yearly professional tune ups with annual heat exchangers. I have a Bacharat testing kit to do the tune up myself but havent used it.

The local System 2000 dealers are very insistent that there are annual cleanings as they have experienced a lot of plugged up units even on systems that dont burn much oil.
 
You may find that lower usage will indeed increase the likelyhood of soot build-up, simply because a hot boiler doesn't have flue gas condensing to the side walls. This happens a lot with pin-type and cheaper steel boilers that worked better for tankless coils and like to be hot. Your boiler is meant to be cold start, and would have to be grossly over-sized to be sooting-up on you. Not to say it can't be messed-up, but with the 3-pass design its much easier to get a low stack temp without condensation. Are you using the boiler to fire an indirect for hot water? If you are then indeed the installer did his job well. This setup while not being the ulitmate in efficency (solar!) it will give the boiler the necessary mass to prevent short-cylcing and add tremendously to system performance.

2 years vs 1 year? It really depends on many factors, but you have 5 heating seasons of experience to tell you its running well at the decreased rate. I'd try to go two years if I had to pay someone. I do the tuneups myself, and vacuum the chamber 2x as often as I change nozzels + filters. A cold-start boiler will tend to soot up if it doesn't get hot enough for long enough. Also, if the return temp of the boiler is too low (often the case with new control equipment) there's a chance condensation can happen on certain spots, and that will attract soot, which will attract more soot that will insulate that spot which will cause more condesation.....you get the picture. That's why a tiny spot can grow quickly, but your nozzles and filters are more of a total mileage concern. If you have access to the rear of the boiler you can check the upper baffles for signs of condensation/soot buildup by removing the smoke pipe. This is usually the coolest point and often the dirtiest. The door on this unit will swing out as well making it very easy to do a full inspection, but unless you have flexible oil lines you will need to disconnect the oil line, then reconnect+bleed the line. Very easy to do depending on your burner (I'm guessing riello).

I think its worth the extra $150 to try it, but someone should inspect the boiler at least 1/yr, that person being you or someone else if you don't feel qualified.
 
I'm no expert on oil boilers . . . but I can tell you that I bought a new oil boiler three or four years ago and I've just been doing cleanings every other year.
 
The buildup that I removed a few months ago resembled lava rock more than carbon. Its a single pass with a pin type exchanger.

The other issue to consider is that if the unit does plug when you are gone or even when you are home that the soot and odor produced is pretty nasty stuff. I realize that the flame safety is supposed to shut things down evantually, but I had to air the house out for a couple of days when it plugged.
By the way, I had switched to every other year tune up as my serviceman had made comments for a couple of years in a row that the unit was real clean and probably didnt need yearly cleanings.
 
firefighterjake said:
I'm no expert on oil boilers . . . but I can tell you that I bought a new oil boiler three or four years ago and I've just been doing cleanings every other year.

I'm with Jake...I usually go every other year....as it seems when I have cleaned every year, they always put the wrong nozzle/thingy on the burner and it ran crappy by the time they left.
 
Status
Not open for further replies.