Propane Boiler and Water Heater Thoughts

My propane boiler for the FHW is on the way out. It is not only 25 years old (worrisome enough), but the pilot light goes out on occasion (I lit it a couple weeks ago and it went out Friday night or Saturday morning). Although I could have it serviced, judging by the amount of interest that I received when I was looking for someone to clean it (none-zip-nada, so I did it myself), that won't happen until maybe next spring. Plus, at its age, I don't think sinking money into it makes much sense.

So, I'm looking at just replacing the dang thing. Considerations:

1. No I rarely use the boiler - just as back up heat (propane is expensive around here), and to run the circulator a couple times a day during deep winter to keep pipes that run thru garage from freezing. Although that could change and it could become the primary heat if I am injured or as I get older, or pellets go up to over $500/ton.
2. I have a separate propane fired water heater that is 6-7 years old. I am not specifically looking to replace it, but am not averse to removing it entirely if it makes sense in the long run (with a 650 sq/ft basement, any square footage gained is a bonus - or a hot water storage tank could be put in its place).
3. I am not looking to swap out for oil because running the oil line would be expensive, oil lines gel up (been there, done that) and I still need propane for my cook stove anyway.
4. Only the main floor of the house is served by the FHW system - 950 sq/ft. Don't know if this makes any difference in options or not.

So, tell me your thoughts on

1. Just replacing the boiler and keeping existing water heater - what are pros/cons of going with just a standard boiler versus a condensing boiler.
2. Replacing both the boiler and the water heater with a combo boiler,
3. Replacing both the furnace and the water heater with a boiler and installing a hot water tank that is run on a separate zone from the FHW.
4. Any options I haven't thought of or other considerations not mentioned?

I would have this professionally done and will have several companies come out to give their recommendations and estimates, but I want to get a feel for what is out there (I haven't had to think about boilers in 10 years), and opinions from people who have no dog in the hunt.

Thanks for any advise you can give me .

 

first question is are you on a well? well water kills on demand hot water (propane ) tanks ask me how I know
I run oil as backup.. I know #2 oil gels can't get much farther north than me in coldest months if tank is outside you put in kerosene it won't gel.. oil lin is plastic covered copper 65 cents a foot... if oil tank is in basement or anyplace over 0 degrees it will not gel... in my area oil is cheaper per btu than propane....

I have FHW oil burner and domestic hot water off boiler separate zone last year 250 gallons of oil for basement heat, hot water, and backup if not home....

 

• Basement not big enough for an oil tank; technically it is, but I don't plan on spending any more of the 650 sq/ft on heating appliances - I already have lost approximately 1/4 of that to FHW, DHW, pellet stove and 2 pallets of pellets. And there is no place to put a fill on that side of the house because that is where all the exhausts are plus the electrical service - I can't even begin to make clearances to that.
• The only place in the yard to put it is on the opposite side of the house from where the boiler is, and out in the middle of the yard (no - can't go against the house because that is where my small propane tanks are going - which I would still need even if I changed over to oil) - 60 feet away.
• If I put it up in the middle of the yard, I would have to have someon level an area, pour a pad and built a shelter for it (means more $$ - and hiring several different trades)
• I am not worried so much about the tank gelling - it is that incredibly long line I would have to run outside. Even with Kerosene in it, it will gel (ask me how I know - see previous bullet point about running oil for 25 years). Plus, I just don't have time to Ef with trying to make sure I get kerosene, or even just to get 15 people in to build and set up everything.
• I understand oil is cheaper (I ran oil at my last place for 25 years), but also know my limitations and my current situation. That's why I took oil off the table

Oh, I'm on town water/sewer, with relatively soft water, so that isn't really a concern.

 

You might be able to find a used or NIB system to save some money.

New-in-Box...unopened...Combination Boiler/Tankless Hot Water


How much propane do you use and what is your BTU requirement for heating when you aren't able to use the pellet system? Do you own your propane tank? What size is it? I only have a 100 lb tank for my cook top but realized that even if I was to have to fill it every 3 months, it would be far cheaper to transport it to get filled instead of having someone come to the house to fill it. I ended up turning in the company owned tank that was at my house and bought my own tank.

Do the pipes that run through the garage need to have water in them in the winter time or can they be isolated with a shutoff valve and drained? Would it be cheaper to run heat tape on them and insulate them? Heat tape would keep the pipes at 50 degrees while your boiler would likely put 160 degree heat into them greatly increasing your heat loss. I've used this stuff in the past with good success in an uninsulated crawl space under a house.

I've been researching oil boilers but it seems that with the infrequency I use it, the added cost of a condensing boiler wouldn't be worth the added cost over a conventional boiler. Not sure if the price difference is the same for propane boilers. Condensing boilers are certainly easier to vent and the savings go up as the cost of fuel goes up (i.e. expensive propane).

Sounds like a combination boiler would be best for you given your limited space..

Good luck.

 

I currently use 100-150 gal/year of propane. But when I've used the boiler, that turns into 200-300 gals/month. Of course that is with an old unit that is probably somewhere around 65-75% efficiency. I have no idea about BTU's needed. There are several reasons I am hiring professionals to do the job - and that is one of them.

I do not own my propane tank. I currently have a 500 gal/tank, but am changing companies and the new company is putting in two 125/gal tanks since I told them that my boiler is not primary heat source (they were originally going to put in one tank, but I asked for two in case I do need to use the boiler)

The pipes that run thru the garage only need water in them if I want heat in my bedrooms (and the rest of the house since it is one big loop) . If I am home, and able-bodied, that is not a concern as I can use pellets. But it also means that I can't leave my house for more than a couple of days, or have any kind of accident or illness between mid August and mid April.

Heat tape would have been a great thing to think of the winter of 2013 when I tore out the garage ceiling and drop boxes (where the pipes run), installed insulation and had someone come in to put in new sheetrock. But I didn't have pellet stoves then and didn't know how incredibly much propane this little place uses, so never thought the water would be sitting for long periods of time when it is cold out.

Thanks for your thoughts on condensing boilers not being worth the extra money if they see limited use - that is a good thing for me to keep in mind!

 

Well water is only as bad as you let it be. On demand water heaters are no different than a standard water heater if you don't maintain them. Personally I would look into navien or renni (not sure that one is spelled correctly). I have installed both of these in well water applications and as long as they are maintained you will be very happy. They both make combo units.

 

There should be a plate on your current boiler that says what the BTU input and output are. Assuming the heating requirement hasn't increased since the boiler was installed (no addition to the house or insulation removed), that would be a good starting point to size your new boiler. If significant improvements to insulation and/or air sealing have happened in the last 25 years, you might be able to go with a smaller boiler. Copy all on the rest of the story... Good luck..

 

That is helpful - I'll look to see if the plate mentions the BTU. I have been working on improving insulation and air-tightness in the last couple of years, so I shouldn't need any more than my current boiler is rated at.

 

Ah, specific name brands to look at - than you for your direct experience opinion!

 

If you were to consider oil, check with your home owners ins. co. about a interior oil tank. Up here the ins. co's won't even look at a house if the tank is interior dwelling.

 

If you're going to do a combination system, make sure you account for the extra BTU's for heating water.. I think with some systems you can put the priority on the hot water production when there's demand. Worth doing some research on this. As you said, you're using a professional so that'll help.

When it comes to propane and cold temps, keep in mind that you're not guaranteed to have unlimited flow at the coldest temperatures.. As propane is used, the process of boiling the propane cools the tank. If the tank can't boil the propane fast enough to keep up with demand, flow is reduced until the tank can heat up to the boiling point again. Your plan to have two 100 gallon tanks should help to reduce the problem of flow reduction.. For any propane burner, though, it's good to be educated on the potential problems with propane in cold weather and during high demand.

http://www.documentation.emersonprocess.com/groups/public/documents/bulletins/d4500147t012.pdf

 

I never even considered extra BTU's for DHW in a combi-system, so that is some good info so at least I can tell if someone is being fair in what they tell me I need, or selling me a bridge in Brooklyn .

That is some interesting reading at that link - too bad I'm not smart enough to figure out what it says besides the lower the temp & the lower the pressure in the tank, the lower the delivery of gas .

 

bogieb I am not familiar with new Hampshire utility company's here they have something called efficiency vermont.. especially if you are retired or on a lower income.. considering your small space requirements.. this seems totally backwards but don't rule out electric.. a condensing hot water tank.. think regular electric tank with refrigerator condenser on and new mini split.. could do all your asking.. for an increase in bill of 50 a month and another 50 (here) to rent to own them... boss just did this at his house family of 3..

 

Not retired or have what is considered low income - especially for a single person.

Part of my objection to electrical is the cost per kw in NH, but also I only have 100 amp service (and have recently used up the last circuit on the panel) so I don't know if it would need to be changed out. Doesn't hurt to look into it a little more though.

 

Crown boilers are extremely well built, some are actually buderus German built units. We have a lp crown boiler at the cottage, but don't use the dhw portion. It mounts on the wall, very compact. it's been in use for about 10 years.

My father owned a plumbing and boiler shop, and I worked for him for a couple of years. We used crown boilers when possible because they were will built, and easy to install.

 

I put a new Burnham NG boiler in about 4 or 5 years ago, bought online from a company out of NY. I really like how it's made, I'm not an expert by no means but surfed and researched reviews for quite some time before pulling the trigger.

Also on the garage deal needing some circulation in the winter this little device is the cats meow....Raybonz turned me on to it. ThermGuard

 

Thank you for another name to look at for boilers.

Love the ThermGuard - have used it the last two seasons to run for 8 minutes 3x/day in late January into mid February or so.

 

Here is the company I bought mine from: SupplyHouse.com - Plumbing, Heating & HVAC Supplies - Formerly PexSupply.com

 

At first I thought that said "Formerly PetSupply.com.

Thanks for the link!