1920s home needing Oil to Gas Conversion in Greater Boston...where to start

TechieTechie

New person, not very mechanically inclined, don't know where to start.

I have a 1926 farmhouse in greater Boston, 1.5 stories @ 950 sq feet of living space. 5 rooms, LR/DR/Kit on 1st floor, 2 bds + bath on 2nd floor. (6 radiators, 2 in LR, none in bath). Late 80s Weil McLain oil fired steam boiler (with internal, on demand water heater), vented into the original center stack chimney (non structural). Only attic floor insulation, and gas is already in the house (gas dryer and line for gas stove).

Just had the boiler's annual cleaning. It's had a crack for quite a while, but the tech said the rotting is getting worse...may not last the season. Not surprised, as I have to fill it up every 5-6 days, keeping the house at 65 during the day, 60 at night (just me and the dog, I don't mind wearing a sweater). I was hoping to put off the conversion until I do a full gut renovation, but I may not have a choice. I require 4 oil tank fillups (175 gal) a year. I plan to stay in the house at least 10 years (and/or if I sell, I will certainly make a profit).

So, here is my wish list.

1. I want to switch to gas.
2. I would prefer to keep my radiators (don't need/like AC except for about 2 weeks a year, can rely on window units). I understand I can switch them from water instead of steam (the radiators all have a big screw on the top side). Is this super $$$$?
3. I would prefer to move my boiler to an outside wall and take down the chimney (If I move the chimney, I can reconfigure my very small kitchen to a nice U shape). But I am assuming I would have to repipe the entire house. I am assuming this would be BIG bucks. Am I wrong? If lining the chimney (and keeping the central location) is going to offset the cost of laying new drain lines (allowing me to move the boiler), I'd rather do the the latter.
4. I would like to plan for a 250/300 sq foot addition (tear down side entry, add 1st floor family room/half bath, add master bedroom up) off the side of the house, likely to be built in a latter phase. Do I include this in the sizing for my new heating system? I am NOT entirely confident the full addition will be built, I may just tear down/rebuild side 1st floor entrance and 1/2 bath (less than 100 sq feet).

Don't need dual zones, fancy stuff. Just basic cost effective heating and hot water. I don't think the house would ever have more than 2 adults and 2 kids (no more than 1.5 baths)...my lot nor my neighborhood would ever warrant it.

Happy to provide any/all pics (or layout) if need be.

Just want to know how to guide the conversation when I have installers come out for estimates.

Thanks

Techie

PS...mods, feel free to move if I have not posted in the right place.

nicholas bonham-carter

There are no zones available with steam without costly, and unreliable features, so it’s good you don’t want that.
You will have to measure your radiators, and calculate their EDR, expressed in square feet of steam, in order to size the boiler. Do NOT merely go off the previous boiler size.
The installer should follow the instructions in the manual for pipe sizes, and layout. If he suggests some deviation, or says, “I’ve been doing it this way for 30 years”, show him the door!
He must install the required skimming port, and use it to clean the boiler, while also showing you how to do it, as it should take several sessions of several hours. If you have a floor drain, it is easier to put on some temporary piping over to the drain, otherwise, use a bucket.
If you have a choice of boiler configuration, choose the safeguard LWCO, instead of the cycle guard, and have him install a 0-3 psi low pressure gauge along side the pressuretrol, so you can see the real pressure of the system, in ounces, as lower is better.—NBC

TechieTechie

Thanks Nicholas.

1. Given that my boiler is a gazzlion years old and that I've converting, it is safe to assume that they will need to repipe anyways? Good news is that both upstairs radiators share a wall (and first floor access to said pipes is easy as well). Ditto with the new bathroom radiator.

2. I seem to get conflicting info on this site as to the best site to calculate EDR. Is there an easy one a newbie can use?

Thanks

Jamie Hall

OK. First, on switching to hot water heat. Don't. Contrary to what you "understand", if those radiators are original -- which they probably are -- it's unlikely that more than a few of them will be able to handle the pressure of hot water heat (roughly ten times the pressure of steam) without leaking. It's even less likely that the pipes will be able to take the pressure, never mind being arranged in such a way as to be usable. My own feeling is that if you do want to switch to hot water heat for some other reason, you should plan on taking the entire steam system -- boiler, pipes, radiators, the works -- out and start all over again with properly sized emitters (radiators? Baseboard? Radiant floors?), properly arranged piping (zones?), and a properly sized boiler. Anything else is a poor compromise (there is a more earthy word for it, but this is a family friendly forum...).

Major money.

Depending entirely on the layout of the steam mains, it may or may not be relatively simple to change the location of the boiler if you keep the steam. Obviously, if you go to hot water you can put the boiler anywhere you want it, since it will be a completely new system with nothing kept from the old.

You are probably right in supposing that switching to gas will require relining the chimney. If the flue is large enough and reasonably straight, this is a minor (relatively speaking) cost. If you plan to move the boiler to the periphery it will have to be vented somewhere. Only condensing gas boilers can be easily and cheaply vented out the side wall -- and they are only for hot water heat. Otherwise, you will need a new venting system in the new location.

You should be aware that changing heating systems -- whether as simple as a new gas boiler for your existing steam system or a new hot water system -- is not going to save energy. It may save money, as natural gas is less expensive than oil (so far... when it's not cut off to make electricity instead...) but it won't save energy (much. A top end mod/con boiler, properly installed and all controls properly adjusted, may be able to save as much as 5% -- 35 gallons of oil equivalent -- a year). Money put into better insulation, sealing air leaks, storm windows, that sort of thing is much better spent.

Sizing. If you are just replacing the steam boiler, then the boiler is sized to the connected radiation in EDR -- not to the heat loss of the house. If you are tearing it out and putting in hot water, that -- to function properly -- must be sized to the actual heat loss of the structure; there are very good on-line calculators to do that (I prefer Slant/Fins -- which will also tell you what you need in each space for radiators or baseboard -- but there are others.

Hope this helps.

TechieTechie

Jamie Hall said:

OK. First, on switching to hot water heat. Major money.

You should be aware that changing heating systems -- whether as simple as a new gas boiler for your existing steam system or a new hot water system -- is not going to save energy. It may save money.

Sizing. If you are just replacing the steam boiler, then the boiler is sized to the connected radiation in EDR --

Hope this helps.

Wow, Jamie, super helpful. So, it sounds like the most cost effective route is to keep steam (which I don't hate, actually) and work as best I can with the existing chimney. My radiators are original (tho they need to be sandblasted and repainted as they are currently painted GREEN!!!).

The house is very compact, so I'm okay with not saving a ton of energy (tho I will add insulation when I do the rehab).

So, then the only question that remains is if I include the 2 or 3 potential radiators for the addition (1 in the entrance/bath, 1 in the LR, and 1 in the bedroom)...in the EDR calcs for the new boiler. I am 90% sure I will at least add the downstairs entry/bath, but very unlikely I will add the full addition (unless a hubby comes into the picture). I just hate to dump money into a boiler and either me or the new owners will have to replace it. Sounds like I should plan for the small addition (less than 100 sq feet), but not the full one. Make sense?

Jamie Hall

Yes, you do make sense. I would certainly plan for the small addition (and do it and enjoy it). What I would also do, though, is make sure the new boiler is small enough (sounds odd put that way!). Boilers are generally sized by EDR, as I noted -- but that size includes a generous allowance for "pickup". Usually 33%. So, in this instance, I would make sure that the boiler chosen has an EDR which is certainly not greater than, and preferably a little less than, the existing system plus the addition.

acwagner

Regarding #3, we did just that. We moved the boiler to a new location and switched to venting directly outside using a power vented boiler so we could eliminate the chimney. Reason was to gain space in a small kitchen.

I wouldn't say it's big bucks, but that's relative. PM me and I can give you an idea of what we paid.

But it all depends on your piping configuration. It may be feasible without major piping changes, might not. We might be able to figure it out if you post some photos of the boiler setup.

Also you need a location on the side of the house that is suitable for venting. There are various rules on proximity to operable windows, sidewalks, roof overhangs, etc.

gfrbrookline

I would reach out to @New England SteamWorks to help with your boiler replacement and adding additional radiators. There is no one better in the Boston area than Ryan when it comes to steam.

gfrbrookline

I find it sad that in Boston, where we probably have the second largest population heated with steam in the country and we only have one steam expert. I have tried several of the local large heating companies that "specialize" in steam and have been told way too many times to turn the pressure up, so the tech's are not trained in steam.

TechieTechie

acwagner said:

Regarding #3, we did just that. We moved the boiler to a new location and switched to venting directly outside using a power vented boiler so we could eliminate the chimney. Reason was to gain space in a small kitchen.

thanks, but if I cannot have direct vent steam, then I don't think its worth it. But I would be interested in the price, I'll PM you.

mattmia2

Power venting allows you to vent a conventional appliance out the sidewall. If up can identify a chase, you could also use a conventional metallic vent system in a new location.

You could potentially heat the addition off a hot water loop from the condensate of the steam boiler or you could install a small mod con for that space.

You might think about a couple min splits for AC.

Zipper13

Where in Greater Boston are you? I'm on the North Shore and too far away to travel for some steam guys I've called in the region. So another resource would be @Charlie from wmass. My wife didn't approve my budget for work from him this year, but many have recommended him to me and he was willing to make the trek from Springfield to the North Shore.

Consider also, that MassSave offers rebates for some new gas hot water boilers, but I don't think they offer anything for a steam boiler replacement. There is a smaller rebate on new oil boiler too. both need to hit specific efficiency minimums to qualify , though.

ethicalpaul

> @TechieTechie said:
>
> 1. Given that my boiler is a gazzlion years old and that I've converting, it is safe to assume that they will need to repipe anyways? Good news is that both upstairs radiators share a wall (and first floor access to said pipes is easy as well). Ditto with the new bathroom radiator.

Where you are asking about repiping above, it looks like you are talking about existing radiators. You almost certainly will NOT need to repipe any existing radiators unless you move them. Even if you move your boiler I think it’s likely you’d reuse your main piping and radiator supply pipes all in place.

You almost certainly will need new near-boiler piping, consider it part of the boiler installation.

> 2. I seem to get conflicting info on this site as to the best site to calculate EDR. Is there an easy one a newbie can use?

The best site to calculate EDR is Amazon where you buy Dan’s book, the Lost Art of Steam Heat.

But honestly given the size of your place even with addition, you are going to be right at the bottom of modern gas steam boilers and even the smallest one may be a bit oversized. That’s OK.