Why are they keeping it so warm (68) at night?

I'm assuming they don't have access to natural gas. Is that correct?

How much is electricity cost in rhode island. I would suggest heatpumps. I realize they don't have ductwork but there is always mini-splits.

Maybe call a hvac-tech to investigate if there is any problems.

Elimintating the boiler from generating hot water is a good idea. If it is not too costly, you should get a gas fired hot water heater.

I couldn't tell from your post how the age of the current boiler. If it is not too old, then you should investigate if converting it to gas is feasible. The price difference between heating with oil and gas is huge. The pay back could be quick when you consider the amount of oil now buying used.

Well, first of all their oil consumption for an older house with 1960's insulation is not "out of the ballpark" at all. Based on the current price of oil, their heating bill is right around $500/month. That's not uncommon, especially this winter which has been cooler than many. Having said all that, you may need to find a tech who really knows hot water heating and make sure that your aquastat, differential etc. is set properly. It is likely that the boiler is firing at a higher rate than what is necessary and this will waste fuel. A house that size should not be firing more than .75gph. First thing make sure the nozzle is at least that small and then, have the burner guy check out the aquastat and set the barometric damper at -.01 or -.02 modern burners don't need more than that and anything higher wastes fuel. As far as switching to another fuel, well, natural gas is less expensive - right now- but historically they've been much closer in price per BTU, currently the difference is greater than it has been and it may or may not continue. What you definately DO NOT want to do is to is even think about converting to propane, it is substantially more than heating oil, has been, and will be; it, like heating oil is a product of the oil refining industry and will always be a more valuable product per btu thereof. Having an oil boiler heat your domestic water is about as efficient as it will get for domestic water heating. Replacing what you have now for domestic water heating with propane ($$$) will cost more money to operate. any time you look at the price of propane vs. heating oil always be aware that propane only has 90,000btu/gallon to heating oil's 140,000btu/gallon. be sure to take that into account to find your price per btu, typically propane is almost always substantially higher per btu. Btw, the reason your old, large, cast-iron boiler didn't have large temp swings was simply because it had much more thermal mass and water capacity, temp increases and decreases were smoother and slower.

Those are good points by berlin, especially about the efficiency of the water heating. There are plenty of oil-fired DHW/hydronic heat boilers that provide great water heating. They are more like demand water heaters than not so they don't have the standby losses. If it is not working, a good pro should look at it. The hot water difficulties could be caused by liming in the heat exchanger. Adding the tank might seem to fix it, but might also cause inefficiency.

Thanks for the replies!

My mistake, the temperature on the 1st floor of the house is kept at 65 degrees, the 2nd floor at 60 degrees, and the patio room at 68 degrees. My father tells me that when he sets the temperature of the patio room (at night) to 65 degrees, it takes "forever" to get to room temperature in the morning when he bumps to temp to 68 or 69 degrees. That is why he leaves it high at night. Of course, he's the kind of person who fiddles with the thermostat all through the day. I have to show him how to program the temperatures in, so he'll be able to keep the temp of the patio at 65 at night until maybe an hour before he wakes up...

My parents have a propane stove and a propane grille tied in outside. There is no natural gas in their area.

The problem that I have with the amount of oil they are using (in relation to the size of their house & insulation) is the fact that they never burnt this much oil with their previous boiler (the current boiler is about 12 years old). Again, I have no idea as to what size the old boiler was, and I haven't checked the output of their new boiler.

Now, if hot water is most efficiently heated using an oil-fired boiler, does this hold true during the summer time when no space heating needs to be done by the boiler? I can understand that in the wintertime, the boiler is already hot from heating the house, so you almost get "free" DHW heating. But, when the boiler is burning oil just to maintaining 120 or 140 degrees in the summer for DHW... Is is still more efficient than a gas (propane) heater?

Also, when this boiler eventually needs to be replaced, is it worth replacing it with a cast iron boiler vs. one with an aluminum or stainless steel heat exchanger?

I would never think about converting the boiler to another fuel. With the expense involved and the increase in price, it just isn't worthwhile. Now, if they had natural gas, that's another story. But with propane, its unrealistic.

I haven't gone over to check things out yet, but I'd just like to find out some possibilities so I can rule things out...

Nick

A few things, make sure there's no air in the water lines, and that the burner is using a nozzle that's .75gph max. Make sure the barometric damper is set on a max of -.02" . These things are very simple for a tech or even a homeowner who's technically inclined to check. yes, a boiler using a water storage tank is much more economical even during the off-season; for example a basic propane water heater (nevermind the increased cost of the fuel) will be very inefficient: 35-60% is usually the range. Your oil boiler (properly setup) will likely be from 75-85% and that mostly holds true during the summer. The boiler may be oversized, overfired, misadjusted etc. someone who knows what they're doing needs to look at it. I wouldn't bother with stainless steel; Cast or steel boilers will last from 40-100+ years and deliver cost savings and excellent performance, stainless also comes with its own list of potential issues and problems as the boiler gets older - stainless tends to crack and pit easier than even steel boiler plate under certain conditions. BTW, your father constantly playing with the thermostat isn't doing his wallet any favors; if he wants to save money get a programmable or set his current one and don't play with it. Also, water heat isn't like forced air, it will take a while to respond to different thermostat settings, but just to be sure, check to make sure there is no air in the loop.

These are some companies that make great boilers: http://www.buderus.us/products/oilheating/oilconventional/
http://www.usboiler.burnham.com/products/residential-boilers-indirect-water-heaters/mpo

Thanks. I'll definitely check for air and make sure the vent valves are working properly. How does one check the nozzle size? Is it printed on a plate on the burner or on the nozzle itself?

I haven't looked the boiler over, so I have no idea what temp their aquastat is set to, let alone the MBTU rating of the boiler. I've got to spend a good day up there checking things out.

BTW, how would the Boilermate be piped in? Is it own it's own zone which calls for heat when the temp in the tank drops? Or is it connected up to the DHW coil?

How does one check and clean deposits in the tankless coil or the boiler itself? I'm almost positive they are running plain water through the loops; there's nothing treating the water...

Thanks,
Nick

There will be no mention of the nozzle size on the burner plate, but rather a range of acceptable nozzles. To check the nozzle size, remove the four small screws between the blast tube of the burner and the fan housing and gently slide the assembly out; the nozzle size and angle will be listed on the nozzle itself. you may have to shut of the oil supply and disconnect the line to do this. If it's a becket burner, look down the blast tube with a light and be sure the retention head hasn't burned off, if it has, you'll have to remove the three bolts that hold the blast tube and flange to the boiler and slide it out, the retention head is held on with two small screws and is easy and cheap to replace, for a .75gph nozzle, you'll need an "F-3" retention head available at any parts store for a few dollars. With a .75gph flow, regardless of combustion chamber size an 80� hollow pattern nozzle is usually best. If you install a new head and nozzle, you'll need to adjust the air/electrodes. Electrodes, 1/8" inch in front of nozzle, 3/16 above the leading edge and 1/8" gap. Air, adjust the air band untill the flame tips begin to get dark and smoke, then open the air band untill it just stops (it helps to hold a flashlight into the barometric damper opening to be sure when all smoke ends), then open it a bit more to be sure. It's reccomended that after this initial setting someone at some point contacts a tech to set it up exactly w/ a bach kit.

Keep in mind that the lower the temp on the aquastat typically the better the efficiency and lower fuel consumption, but if there is baseboard heat, you'll lower the max btu output, which may be ok, but be cautious about lowering the temp too much.

you are correct, typically the storage tank is run on it's own zone just like any other zone in the home, the coil is either removed or capped.

The only deposits you will have to worry about are combustion related deposits in the flame side of the heat exchanger, a pro will have the proper equiptment to clean all of the hard-to-reach areas, but a good brushing down with a small broom or stiff brush to the areas that you can access won't hurt at all. In a pressurized hot water boiler, provided there hasn't been a constant leak in the system (so that fresh water is always entering) you'll have no scale buildup or problems on the water side of the boiler, the best thing you can do there is leave the (black) water where it is.

Wow. Thanks for the great information Berlin!

When they renovated the house, they were able to put plenty of baseboard in each room. When I was thinking about all of their baseboard, though, I remembered that they had LOTS of big bulky furniture blocking large sections of baseboard in most of the rooms in the house...

The dining room has a large buffet/hutch which blocks about 50% of the baseboard on that wall, on the other wall of the dining room, they have a set of base cabinets they use for storage and as a buffet, which were installed after the baseboard, and therefore are blocking the heat on 90% of that wall. In the living room and patio room, both have couches blocking a large section of baseboard. Of course, most of this blocked baseboard is on the outside walls of the house. I'm definitely going to have to get rid of some excessive furniture and move other pieces...

Baseboard might give off 500 BTU/HR per foot at 180 degrees, but if only 5 feet rather than 15 feet of baseboard around the outside perimeter of the room isn't blocked, the heat output would be terrible... Maybe someone tried bumping up the temperature of the aquastat to compensate and get more BTU's out of the baseboard? These are all things I've got to check.

Another question. Right in the very center of the house is the stairway to go upstairs. If the thermostat is heating the 1st floor, and the heat on the 2nd floor is turned off, all of that heat would rise up the stairs and into the bedrooms, correct? Would it be beneficial to turn on the heat upstairs? Would that reduce the rising of the warm air from the 1st floor?

I know they don't have separate circulators for each zone, but instead, have 1 circulator with 3 zone valves. For some reason, I don't remember ever seeing an addition fourth zone valve added after they installed the boilermate... I'll be checking this too.

Thanks Again,
Nick

Hello Again.

I went over yesterday to check things out. Their boiler is a cast-iron (I was wrong...) Utica SFH-4150W. The DOE capacity is 175 MBTU. According to the inspection sheet that was filled out in 2001, (I'm assuming that's close to when it was installed), the burner (Beckett AFG) nozzle is a 1.10 at 80 degrees. (The plate says the nozzle furnished with the boiler was a 1.25 at 80 degrees) The Gross stack temp was 500 degrees, and the net stack temp was 450. There was 14% CO2 and 0% smoke. The overall efficiency was 83.75%. See attached image.

On the tag, the breach draft was -.03", and the overfire was -.02". An interesting find, however, was the fact that the damper was forced open with a sheet metal screw through the bottom of the damper... Why would someone do this? The chimney is old, but it has a good draft... Without having a manometer, is there any safe setting I can adjust the damper to? I know it should be closed when the boiler is off, and it should flutter around on a windy say, correct? See picture.

The aquastat settings were 200 degrees high (which seems quite high to me, considering the fact that every room has plenty of radiating area...), and 140 degrees low. The differential was set to 10 degrees. Perhaps someone bumped up the temperature of the boiler to compensate for the domestic hot water problems? There's a Beckett HeatManager installed.

Curiously, the GPM rating on this boiler is 4.0 GPM, which was more than enough for their 1-bath house. I'm not sure why they had problems with it. The Boilermate is a 41-gallon model. See picture.

The boiler has 4 zones: 1st floor, 2nd floor, patio room, and indirect-fired water heater. There is a single circulator on the return, with the zone valves upstream from the circulator.

Just a side note, 95% of the exposed boiler piping is completely insulated. Some of the near-boiler piping isn't but the horizontal runs throughout the basement are all insulated.

While I was there, I took measurements of the house to do a heat loss calculation.

Nick

I wonder if the screw isn't a securing screw for the device and was too long.

You can't set your draft without an instrument. If the damper is open too far, you'll reduce the draft in the boiler, possibly causing fumes or inefficient combustion.

Your high limit setting of 200 is only a safety. Your boiler will run close to 140 unless you are under radiated and then it will run off the high limit. 200 sounds scary, but it's not. Normally, the settings are 160/180 and if under radiated, some set the numbers at 180/200.

4 gpm must be the max allowed because that is for half million btuh boiler, industrial size. Your nozzle of 1.10 is typical and it could be less. Typical houses are 80-130K btuh approx.

Your CO2 is high. Most run around 11-13%. You can overfire at that high.

A manometer is great, but it's not necessary. set the baro weight at -.02 on the baro, The burner in your boiler can fire positive without a problem, however that won't happen with your setup even at .02 (on the baro) Downsize the nozzle to .75 gph, you don't need more than that with that house; a heat loss calc will be great, but if anything you might be lacking on baseboard, not firing rate. with an interior chimney and a boro (dilution of flue gasses), the dew point will be lowered such that you don't want a stack temp that high, it's unnecessary. Whether the baro remains open when the boiler's off or not is irrelevent, it may or may not,(probably will if set properly) what you want is to set it as for as low a draft as possible to keep your efficiency up, which, on that baro, is -.02 on the weight (which might be slightly lower or higher than that if checked with a manometer, but if it's plumb and level, the factory settings will get you very close).

Turning on the heat upstairs would keep downstairs heat from going up, but it can not lower your heating cost. That would only increase it by increasing the upstairs temp. The only reason to do it would be to decrease drafts or if the downstairs system can not keep up. It will only increase cost.

In one house that I rented in Tompkins County NY, we had a couch next (parallel) to the stairs. You cold feel the cold air cascading down your back when sitting there in the winter. I used to think of it as a waterfall. We did not want to spend the money to heat the house more so we just pulled the couch out 2-3 feet on cold evenings when we wanted to sit.