Old boiler pictures / question update.

gyrfalcon

First time post.  I can provide more details momentarily.  Is cast heat exchanger normal? I can’t tell if there is a wet spot . 

gyrfalcon

gyrfalcon

Omit the wood stove chimney picture, somehow it snuck in .

Alan (California Radiant) Forbes

Looks like it needs a good cleaning. I can't tell if that's a wet spot either. Could be a stain, but it's not in a place where you normally see a leak. Gently remove the corrosion from that location to learn more.

gyrfalcon

My wife says I am looking for a reason to replace it. This may be true... HaHa
The boiler works but is old and I feel oversized for my house and baseboards. I have had a few contractors take a look. One of them put a new gas valve on it last year and was supposed to clean it and measure flue readings but did not actually do it. Awaiting load calculations, however most seem reluctant to even perform manual J and just want to replace the old beast with a mod con.

gyrfalcon

As a side note.  I found one of my baseboard fin tube section to be incorrectly installed.  I gently twisted the fins into proper orientation.  We will see how this affects room temp and boiler run times. 

gyrfalcon

gyrfalcon

And after 

Steamhead

That should help! Let us know.

gyrfalcon

I will!!  I’m not going to attempt a cleaning on the heat exchanger until cold weather is done.  Btw.  The boiler is a Slant Fin Galaxy from probably the early 80s.  I’m partial to keeping old reliable stuff going but often wonder if I should plan on replacing it Before it dies. If it ever does.   Any input?  

EdTheHeaterMan

gyrfalcon said:

Omit the wood stove chimney picture, somehow it snuck in .

you can edit by going to the 3 dots at the top right of your comment

EBEBRATT-Ed

@gyrfalcon

Have the boiler cleaned and combustion checked. If it's running ok keep running it.

EdTheHeaterMan

gyrfalcon said:

I will!!  I’m not going to attempt a cleaning on the heat exchanger until cold weather is done.  Btw.  The boiler is a Slant Fin Galaxy from probably the early 80s.  I’m partial to keeping old reliable stuff going but often wonder if I should plan on replacing it Before it dies. If it ever does.   Any input?  

You will need to replace it when it starts to leak. This summer, when you take it apart to clean it, look closely at the cast iron to see if there is any growing wet spots that are from one location. Don't be confused by condensation though.

If it is not leaking, then you can just repair parts that break. That is a very simple to fix heater and generic parts are available if Original Parts are unavailable.

gyrfalcon

Thanks everyone.  

gyrfalcon

I have yet to take on a thorough cleaning. I will likely wait until heating season is over. In the mean time, I have had few contractors come look at my system and give me some advise on future replacement options, when the time comes. Here are some thoughts and options. I would appreciate any insight from ones here.

Most, if not all contractors seem reluctant to do much with my old boiler, let alone perform a Manual J or load / heat loss on my house. I cannot find any recommended companies in my zip code(47408) search on this site. The last company that did any work on it was supposed to replace the gas valve, inspect, clean and tune it up. The valve was successfully replaced but they did not clean heat exchanger, check combustion, or set pilot. I actually found the pilot light to be missing the LP orifice somehow and had to replace that myself for pilot to function properly. That tech has since been fired, not because of my pilot, but another mishap elsewhere. I am reluctant to call on that company again...

I have ran my own rough numbers using Slant Fin and US Boiler apps. and come in high 50K btu and low 60k btu for my house. ( Orig build yr 1976. 1965 sq ft, single level, half on slab half on crawl. south facing but bermed into hillside. 15-18 ft cathederal ceilings and or clerestory in some rooms. 65f of coppertube baseboards split into 2 zones. Aquastat set to 180-160 and Tstats at 65-70. I also have a wood stove in living room with an attached 10x30 sunroom.

I like the idea of a mod con with indirect but am not sure if it will work and I have not been convinced by any contractors thus far. It seems my current boiler is too big for my house and too big for my baseboards. So far lots of companies are trying to push a 110 Lochinvar , Navien or some equally large cast iron for cheaper option. I have more details if anyone has questions. Thanks in advance.
I am trying to have a plan in place rather than knee jerk reaction if the old boiler gives up on me.

EBEBRATT-Ed

65 feet of baseboard will output 40,000 maximum if it is standard 3/4" fin tube

Ther is no point in installing a boiler larger than what the baseboard will output.

An indirect will be fine with a mod-con

gyrfalcon

It seems to me that my heat load calculations show my boiler is too big for my house and too big for my baseboard emitters.  Baseboards too small for house heat load.  Boiler never runs for more than 5 -6 minutes at a time for either of the 2 zones. One side of house always feels a little cold.  Thermostat setting is 3-5 deg higher than actual room temp.  I really wish I had a local boiler / hydronic person to talk this through with.  I guess since I don’t really have any immediate “problems “ ie no heat or water leak, there’s nothing to “fix”.  

bburd

You might try adjusting your aquastat settings. Hi 200, differential 10. That would get more heat from your existing radiation.

Be sure room air is free to flow through your baseboards, 1” minimum clear space at the bottom (carpeting sometimes obstructs this), dampers open, furniture a few inches from the wall.

Also verify your boiler pressure is adequate, 12 psi cold should work up to a two-story house. Do you hear gurgling in the pipes that might indicate air  problems?

gyrfalcon

Psi is around 12.   No gurgling noises. 

hot_rod

I’d suggest a heat load calc first, see how the fin tube matches the load . Use the calculator at Slantfins website.
A 110- 120 mod con would turn down nicely to your load and give you plenty of DHW power,
Any flame spillage from that boiler, looks pretty plugged in some sections?

gyrfalcon

No flame spillage that I can tell.  I’ll attach my non professional Slant/Fin heat load 

hot_rod

I see an 80- 100K mod con in your future. A combi is another option for heat and DHW from one unit. Plan on a 120 or so to provide 2 gpm or more, if you chose a combi.
Mod con turndown would get you to your exact heat load number around 60K.

I wouldn't worry about a spot on heat load number, it is an ever changing load. It may never be at that calculated number it's a guesstimate at best, but gives you a starting point. The beauty of a modulating boiler is it accommodates your changing loads nicely. It changes output along with a load change or increase.

gyrfalcon

Thank you hot rod! Two of the bigger names in boiler install & maintenance in town have both mentioned Lochinvar.  It seems to be a popular one compared to other brands in my area.  One question regarding brands,  anybody have any info or the newer WM eco tec?  Looks pretty sweet 

hot_rod

It may come down to what you can find, not what you prefer. I think all the name brand boiler companies are turning out good mod cons now. Find a brand with local support and parts availability.  The more expensive models tend to have more options on the controls to fine tune the system

I like features like ramp delay, output limiting, boost function, outdoor reset

Remote monitor and adjusting is sometimes nice if you travel much.

I have owned four Lochinvar at various homes and shops, all have been trouble free, including two combis.

EdTheHeaterMan

I worked on all makes and models in my local area. Service calls is where I made my money. Seems that I seldom worked on Lochinvar products. Did a lot of work on WM products. That sort of backs up Hot Rod Bob's claim of trouble free operation. Not a fan of WM but many of my competitors installed WM. Many of them did not do repair and maintenance. That is where I got my WM customers from. Sometimes the competitor actually called me to solve WM problems. Mostly customers though, who were not informed by the installer about maintenance requirements.

Who reads instruction manuals anyway?

gyrfalcon

Y’all are the best.  I appreciate all of your input. 

gyrfalcon

So I have to ask, is there a way I can estimate any potential fuel / money savings by switching my 80% CI (likely oversized) and 50 gal direct fired lp water heater to a nice mod con w/ indirect tank? ?

Jamie Hall

It will be a guess, but an informed one. If you can run your mod/con at or below condesnting temperatures for the return (140 of so) you may be able to save as much as 10 to 12 percent. Otherwise, not more than 5 percent. Switching to the indirect will not save much on hot water: firing the indirect requires non-condensing temperatures from the boiler, so that will be a tossup. The savings will be on the heating.

gyrfalcon

Will there be a savings on installing an appropriately sized, smaller and newer cast iron boiler?

pecmsg

gyrfalcon said:

Will there be a savings on installing an appropriately sized, smaller and newer cast iron boiler?

There are always saving with a Properly sized and installed boiler.

If you want savings then Tighten the envelope. This will have a much higher return on investment. Once that's done you can now dramatically reduce the size of the boiler and save even further.

Jamie Hall

gyrfalcon said:

Will there be a savings on installing an appropriately sized, smaller and newer cast iron boiler?

Yes, but not much. Not enough to recover the investment if the older boiler is working. As @pecmsg says, spend your money on reducing heat losses.

EdTheHeaterMan

Jamie Hall said:

It will be a guess, but an informed one. If you can run your mod/con at or below condesnting temperatures for the return (140 of so) you may be able to save as much as 10 to 12 percent. Otherwise, not more than 5 percent. Switching to the indirect will not save much on hot water: firing the indirect requires non-condensing temperatures from the boiler, so that will be a tossup. The savings will be on the heating.

I slightly disagree with this. for this reason only. Connecting a 120° to 140° tank full of water to a constantly venting chimney will cause that tank to loose the stored temperature faster than the water in a tank that is (usually) better insulated and not connected to a vent will lower the downtime loss on the DHW tank. Since most water heaters are used about 2 hours a day, (out of 24 hours) there will be long downtimes for that tank. Water heaters are unused for more than 90% of the time.

Since the recovery firing will happen less you will have a savings. How much will be a small amount over the entire gas usage, but when you add up the proper size savings, the modulation savings, possible condensation of flue gas savings (if you can get the return temperature lower for space heating operation, and add DHW down time savings. You MAY save more than 15%, but I would not bank on anything over 20%. It could happen but don't count on it.

So Jamie is mostly correct. I just have experience with many customers over the years and the savings vary from one customer to the next. Gas to Gas, Oil to Gas, Oil to Oil, and even 3 Gas to Oil conversions over my career. All with savings! Some less than 10%, others over 50%. Your situation sounds like Gas to Gas using an indirect DHW and a ModCom, you will be near 15%

Just my guess, but I would recommend it

Mr. Ed

gyrfalcon

I guess in my hopeful optimism the rewards would be worth the cost.  Crunching very rough numbers,  it’s not all that great.  It’s kinda like a good car that is running fine and suits a persons needs, just not getting phenomenal mpg, compared to a Prius .  Btw, I work in the automotive service industry and i never recommend someone to buy a hybrid solely on the grounds of saving money.   Now,  if the old beast (boiler or car) is really dying or not meeting needs, maybe a high efficiency model is a good option.  

 In my mind I was thinking - this old cast iron boiler burns 100k btu per hr. At least 20k goes up and out the pipe.  But if my house only needs 50k-60k btu per hour- that’s like 40-50 % better!!  Really good  if I can get over 90%  Same-wise with the DHW.  I’ve read direct fired, they are only 50-60% efficient, so if I can bump that to 80-95% thats even more savings.   I guess I’m pretty far off….   Thanks again guys.