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New Buderus boiler using more gas each month than 40 yr old boiler

Am about at wit's end. In May had a new Buderus boiler and indirect water heater installed - replacing the original 40 year old boiler and water heater. Dealer claimed that high efficiency
system "save you money". That Energy Star "translates to hundreds of dollars saved each year." How an indirect water heater was more

So you can imagine my shock when after reviewing monthly gas usage, it has increased each month (May, June, July, August, Sept, Oct, Nov, & Dec) since this new system has been in place. And no, we didn't jack up thermostat - new system was installed after heating season was over. Also have cold air blowing now from the heat-o-lator in the rec room - as opposed to hot air. Something is remiss.:eek:

Have contacted the dealer, who initially blamed the gas meter. Gas company came out and said there is no problem with gas meter. The gas guys alluded that perhaps this new system is too large for the house. And that could explain the increased gas usage. Another thought is the new system's indirect hot water heater (old system had a separate gas hot water heater) and its using more since we can't shut off the boiler like we used to during the summer months w/old system. Dealer believes the heat-o-lator system wasn't reconnected properly since there's an indirect water heater now. But he also hasn't sent anyone back out to correct.

Had only heard rave reviews about Buderus so am very confused by this increase in usage. Am extremely disappointed since its an expensive system to begin with, and now costing us more $$$ each month than the old system.

Any suggestions? The dealer has been out twice to check gauges.
Gas company reports no problems with their equipment. Dealer said he has contacted Buderus. The system is guaranteed for 1 year,
so am tempted to have it removed, get my $$$ back, and purchase a less expensive system.

PS - forgot to mention that we also heat with pellet stove. use approximately 2 ton a season.

Re: New Buderus boiler using more gas each month than 40 yr old boiler

I see the initial post had a number of "looks", but no comments.

Recently had the Buderus Logamatic 2107, http://www.buderus.net/OurProducts/Controls/Logamatic2107/tabid/270/Default.aspx installed on G124X (Energy Star rated). Hopefully this panel will help reduce gas usage since no other problems were "detected" by rep tech. :confused:

Still using pellet stove - 2 tons a heating season.:)

Re: New Buderus boiler using more gas each month than 40 yr old boiler

Buderus has a good reputation in the industry for making high quality heating equipment---the indirect HWH and the ODR unit will both save you money---even though the HWH runs in the summer, little gas is used & the tank is well-insulated---- an IHWH is the best way to go to make DHW & there are no flue losses.

The only disconnect I can think of is that the boiler was not sized properly to the house when it was put in---if the house needs only, say, 60,000 btu/hr to heat it on a cold day, & the installed boiler output is over 100,000 btu/hr, then yes, the boiler's too big & will burn excessive fuel.

The installer is expected to do a HEAT LOSS CALCULATION to determine a whole complex of unique things about your house so that the proper size boiler is installed.

A very rough estimate is to take the total square footage of all heated spaces in the house (including cellars & utility rooms) & multiply by 40 (multiplier)---thus a house of 1600 sq.ft. X 40 = 64,000 btu/hr to heat it---Google "heat loss calculation" to get some HLC's that will give you a reasonable estimate of how much heat you need---if you have little insulation in the exterior walls & attic, a lot of windows that are loose-fitting/no storms/ etc., then the multiplier should be closer to 60, instead of 40.

Buderus & other cast iron boilers come in several sizes, and each boiler has 2-3 firing rates, accomplished by adding or subtracting different size gas burners with different orifice openings.

Check the metal name plate on the boiler for its OUTPUT, then compare it with your heat loss calculations.

Perhaps the boiler can be DOWNRATED to burn less of a flame & still adequately heat the house.

Re: New Buderus boiler using more gas each month than 40 yr old boiler

Bet he didn't do a heatloss, bet it is as large as the old one, which is probably grossly oversized, and wasting gas.

Bigger is not better

What is a heatolater?

Re: New Buderus boiler using more gas each month than 40 yr old boiler

> What is a heatolater?

its the wall unit that blows out heat into the basement rec room - in place of baseboard or duct. that's "what" it was referred to but maybe it has a more official name I'm not aware of.

this new boiler was installed in May and promptly used more gas
each month, starting w/the summer months, than older boiler used. that's what doesn't make any sense to a "non-heating expert" like myself.

hopefully the Logamatic panel makes a difference but its a lil'annoying to think that one needed an additional panel, in addition to a new boiler and indirect. why wouldn't the new boiler
and indirect be enough to save on usage (unless you're right and the boiler isn't the right size for the house).

Re: New Buderus boiler using more gas each month than 40 yr old boiler

We removed an old steam system from our 110-year-old house several years ago, replaced it with a Buderus wall hung gas boiler, driving a heating module that was added to our Unico high-velocity a/c system.
Horrible decision. Gas bills for the house went up over 50%. Installation firm has been out repeatedly with no improvement - all they can say is that the house has poor insulation. Old steam system was able to heat the place just fine (even with this poor insulation), for less money. Buderus system fails usually 2x per season and requires frequent service calls. I could have simply installed a newer steam boiler and used all the existing radiators for much less money and hassle.

Re: New Buderus boiler using more gas each month than 40 yr old boiler

I also have a Buderus boiler and am thinking about puting in the Logamatic 2107 for $1,500. They say a 30% reduction in fuel??? anyone with experience? Thanks

Start From Scratch

You really need to start from scratch. What I mean is pretend the boiler and indirect are not there. Have a proper heat loss of the home done and also measure the footage of heat emmitters if fin-tube or cast iron. Same goes for radiators you need to calculate their EDR. If its oversized I would make them take it out. An oversized boiler leads to more maintenace, high fuel cost and increased service calls.

I would then check to see how oversized the boiler is in comparison to the heat loss. There are ways to help short cycling but can't eliminate it. What model boiler was installed? If the boiler is running on outdoor reset I would then, utlizing the calculations of emmitter figure out where the heating curve needs to be and make sure it's riding on the correct curve.

Forty btu's a square is pretty high. Generally R-11 Wall, R30 Attic with decent windows and a 0 degree climate rule of thumb is 32btus per sq. R-19, etc 25btu's per sqft.

What was the increase in therms or (CCF) used per month incomparison to the months prior to the new install. Don't look at dollars look at therms or (CCF) used.

The biggest mistake most contractors make is they don't do heat losses. They look at the lable of the old and just install the same. Doing a heat loss is the only way to correctly size a boiler regardless if there is an existing boiler or not.

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