Replace with steam or upgrade to ???

Lon Henderson

I have a 1994 Burnham V907 boiler with a 702 Carlin burner. The boiler has a crack/leak high enough up that it looks like we'll be able to limp it along for the winter in northern NH (yesterday morning was -26F and windchills of -70+ happen nearly every winter). The boiler heats a 19,000 sq. ft country inn built in 1880 on a single pipe system as well as providing all domestic hot water. Obviously it's a dramatically inefficient system in an inefficient building. We've tightened up the building, but have to do something with the boiler.

My options, as I see it are:

1. Take the beast apart and replace the defective section(s). I don't like this option because maintenance cost have been very high (average of 10k/year for the last 8 years) and because I've heard that replacing a section doesn't always work.

2. Remove the beast and install a new monster of similiar steamy ilk. This option, although more expensive, has some appeal as I'd anticipate lower annual maintenance, a small increase in efficiency and hopefully, a better chance at a positive outcome.

3. Do either of the above and add a separate boiler for domestic hot water. We'll do this anyway as it would remove a lot of cycling load off the main boiler, especially in the warm months. Go figure--in the summer guests can be using so much hot water that some of the radiators charge and then I air condition them . . . This is a no-brainer.

4. Junk the entire single pipe steam system and retrofit the entire place with a hot water system zoned by room. This would make guests much happier since the current steam is always either too hot or too cold for nearly everyone.

My quandry then is over this last option. The challenge is that I have great local support for the first three options, but no local businesses who are knowledgable on a doing a major retrofit. In just the broadest brushstroke, I'd like to know if this is an option that makes economic sense. I.e. roughly what is the installed cost of suitable boiler? What is a suitable boiler? Or would it be a series of boilers? Can the chases and holes that currently support the steam be used to support hot water? Does hot water have enough heat carrying capacity to keep my guests warm? Can such a system also be used for cooling? What is a generic "pay back" time for such a system? Should I also be looking into "exotic" technologies like geothermal?

Any thoughts that anyone would like to post are most welcome. If you are a company in the New England area that would have an interest in this sort of thing, I'd welcome your email to innkeeper@sunsethillhouse.com or phone call at 603-823-5522.

Sincerely,

Lon Henderson

SusanC

Hi Lon, just a HO here, so I don't really have an answer for you. That is best left for the "Pro". I did want to mention that I have seen a picture here where there are valves installed near the boiler on the risers. If the valves were closed, it seems that no steam could get to the rad's in summer for you to then have to air condition away [as mentioned in #3].
Just a thought, and if that is a bad idea, someone more knowledgeable will clarify I am sure.
bruhl

Steve Garson_2

From a financial perspective, stay with steam. You can make it work well with proper venting, TRVs in the rooms and a new boiler. This will allow rooms some temperature control and improve overall comfort. With an updated system, you shouldn't have major maintenance costs.

But hire a steam pro, not just a plumber to do the work. There is a big difference. You will never get a ROI by converting to hot water heat.

tim smith

Regarding heat/cool for your inn

Alot of this answer depends on how important the cooling is to your inn. If cooling were very important, I might be looking into a totally different system, say a Variable speed heat pump w/ mini split terminal unis, they now have heat reclaim so they can heat and cool at same time and regenerate the heat from the cooling areas to the heating areas. Either one are quite costly but if cooling is important?? The variable speed hp I am talking about is the Mitsubishi City Multi. It is the commercial version of it for larger inn.
Alternate: fix steam system up, new boiler, recontrol so you have better zone control, get system in proper working order which it very likely may not be. Others will chime in on this also. Good luck, Tim

Dale

Nat gas?

I assume you have no access to natural gas so your choice is propane or fuel oil. I would change the domestic hot water to propane series on demand units like Takagi or Rinnai. You probably also need high temp domestic for your kitchen and laundry and these work great. The wholesaler will design the whole package for your installer. You will save a ton of $ on fuel. As to the space heat boiler, it depends on your budget now and ROI years you feel reasonable. Best choice is multiple (more cost now) mod cons with all the current controls, would need to be propane. Newest oil, I think burnam, would work and be more effecient with the must yearly service. You could also look into a small mod con for some of the retrofit and a steam for what is left, sized by the rads and piping of course. Good luck.

Steamhead (in transit)

Your best option

would be #3. Though the problem with radiators heating in summer sounds like a control problem, the DHW load is likely much less than the heating load, so firing such a big boiler for a relatively smaller DHW load wouldn't make much sense.

Two caveats with using propane: 1- the cost per BTU is generally higher than fuel oil. Condensing equipment can offset some of this but probably not all of it, and that type of equipment is much more complicated so, depending on where you are, the locals may not be able to service it well.

2- Propane is heavier than air, so if there is a leak it can pool on a basement floor and be ignited. Not trying to be scary, just stating a basic principle of physics.

Combine your TRVs with a Vaporstat to keep the boiler pressure below 1 pound. This will enhance the TRVs' ability to control the radiators. You should be able to distribute steam to all radiators on just a couple of ounces anyway- if not, you have a problem that needs fixing.

"Steamhead"



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Lon Henderson

Thanks bruhl

Dear Bruhl,

To me your idea makes a lot of sense although when I seperate out the domestic hot water, I suspect it'll be a moot point. It's more one of those thing I should have done years ago, but when you have a high-use 128 year old facility, lots of other things climb to the top of the priority pyramid.

Thanks,

Lon

Lon Henderson

Thanks Steve

Dear Steve,

We actually use TRVs in each room and the system balances well when I have no guests. The trouble is most of my guests have no idea how a steam system works and they're looking for immediate gratification. Sometimes it's funny, like when someone complains they turned the valve to closed, but the radiator is still hot. All 300 pounds of it . . . Some of our solution has been to install propane gas fireplaces in all of the "cool" rooms and tell guests to regulate their final temperature with the appliance. Guests are happy. They have control and ambiance.

Also thanks for the advice on the boiler. It sounds as though to you, all else being equal, you'd opt for a new boiler rather than throwing money at the old and not really even consider a full building conversion. Which is where I was leaning before this post.

Sincerely,

Lon Henderson

Lon Henderson

Dear Tim,

This is new information for me which is some of what I was looking for. Fortunately those cold winters I mentioned in my main post also translate to cool summers where we can go several years without hitting 90. For now we're using window units which although innefficient are pretty cost effective for our locale. Nonetheless, I do have some large public areas where this could be a good idea. Again, since it's new info for me, I've to research it more.

Thanks for your reply,

Lon Henderson

Lon Henderson

Thanks Steamhead

Dear Steamhead,

Thanks for some great information. I'll have to check on the vaporstat but the system seems to work pretty well on very low pressure. Judging by my gauge, I have never exceeded one pound and I had a technician verify it was working. Also, the system must be fairly low pressure or I think I would be losing a lot more water to vapor exhaust through the crack than I am. Of course, I know I'm just throwing away $$ each time I look up and see that quickly dissipating plume above the chimney.

As for going with a more complicated system, perhaps I'd consider it if I were in an urban location, but you're right, I don't have easy access to experts in non-standard or more technically advanced systems. The good news is they always come when I call and they care which is better than many can boast.

Thanks,

Lon Henderson

Steamhead (in transit)

You might consider

adding a very-low-pressure gauge which is graduated in ounces up to about 2-3 pounds or so. This would really open your eyes to what your system is doing, as many of our customers can attest. The present 30-pound gauge must remain, to satisfy Code.

Also, if you tell us what part of New England you're in, we probably know a good steam man in your area. Have you tried the Find a Professional page of this site, under Resources at the top of this page?

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"