Present heating design is a failure, advice on zoning and updating heating sources for consistency

LI_CJ

With a number of winters in the books now in this house, I'm continuously trying to improve the comfort level for my family. The heating has been a huge issue - previous owner made changes that have done much more harm than help. As things stand now, 3 stories, roughly 2,500 sf, one zone heating. I have a peerless WBV-3 boiler with a carlin e-z gas conversion burner (converted to gas last season). House is hot water heat.

3rd floor - CI radiators
2nd floor - CI radiators
1st floor - mash up of slant fin in three rooms, and CI at base of stairs and one room. The thermostat for the whole-house heat is in my dining room which has slant fin.

The house, as it currently stands, heats TERRIBLY. When we have cold spells in the NE, the boiler continuously runs and the room with the thermostat can never reach the call temp (67 is what I aim for...when it's single digits outside best it can reach is low 60s). Meanwhile, the upper floors are roasting.

The house was built in 1930 (plaster walls) and while it can certainly use more insulation either in blow-in or other options, I need to address the actual heating woes. Frankly I'm fed up with the family being cold and am more focused on making everyone more comfortable than trying to find a solution that is economical (aka, I'll spend $$$ to make this right).

I have a full basement with a drop ceiling, so I have access to almost all of the heating lines (I think). Here is what I plan to do this spring with the help of professionals, but I'd love some advice on whether or not I should consider other routes to take:

* Zone off 1st floor from 2nd/3rd. This is an absolute must. I am hoping we can accomplish this with with minimally invasive (or zero) in wall work by working from the basement. I have a thermostat for my central A/C in the 2nd floor hallway which I can use for the 2nd/3rd floor heat...need to run a wire there but I'll fish line there, somehow.

**Fix this mismatched mess on 1st floor. I love cast iron given the heat retention and I'm presently leaning towards ripping out the slant fin and putting in cast iron baseboard so that entire first floor is CI. If I add up the existing slant fin, I'm looking at probably 50 ft of base board, so not cheap with CI BB being 3x the cost of slant fin type. Option #2 would be to go the other route and remove the two in wall CI radiators on 1st floor and replace with a European panel type radiator (or Budderus), which if I researched correctly, should work pretty well in the same zone as slant fin type.

Would love some thoughts on this strategy. I feel like zoning off the house is a no brainier, but curious if the premium cost of going all CI on first floor is discouraged (would fin / panel type get the job done when on a proper zone)? I guess other benefit of CI is boiler will run more efficiently with lower operating temps.

Look forward to hearing some thoughts on the above.

Thanks!

hot_rod

Does the room with the thermostat come up to the set temperature? It is tough to control 3 levels from one thermostat location, it would take some delicate balancing. Depending on the piping it may not even be possible.

Assuming there are enough heat emitters in all the levels or rooms, 3 zones might be the best approach for comfort and adjustability.

Jellis

Before you start slicing and dicing, you should do a heat loss calculation to see that you have a reasonable amount of radiation in each room and that your boiler is reasonably sized.
That will help you decide if you need to change the baseboard in the room.
3 zones would certainly go a long way to help the comfort on each floor. As @hot_rod mentioned it would be difficult to balance 3 floors from 1 thermostat.
Look out for any potential freeze points. your upstairs zone will circulate less once you zone it off and creates the potential to freeze where it never did before.

Ironman

The Cast iron radiators should never have been replaced with fin tube baseboards. The output and heat characteristics of the two are completely different.

As mentioned, a room by room heat loss calc should be done and then PROPERLY sized CI rad's (not baseboards) should be re-installed. THEN, and only then, you could look at taking further steps to balance the system.

If this is an old converted gravity system, there may not be any easy re-piping options available to zone it; however, those old systems usually were very well balanced before they were messed with and a good hydronics pro would know how to restore that.

TRVs and constant circulation may be an option after the basic things to restore are done.

Look in the resource section of this site for info about older hot water systems.

SuperTech

A Peerless WBV-03? I have the same boiler and it still has the Beckett AFG. I think it's a fine boiler. The big difference is mine is only 1000 square feet. Did it ever heat well with the oil burner? You have to consider that seems like a small boiler and gas puts out less BTUs than oil, but I haven't done a heat loss calculation on your home.

And yes, they absolutely should have never replaced any cast iron radiatiors, they did you a terrible disservice by doing that. I would start by seeing about undoing that work. Cast iron emitters are superior to fin tube convectors and do not work well together unless they are on different zones away from each other controlled by a different thermostat. If putting the radiators back isn't an option maybe you can have some cast iron baseboards installed.

Brewbeer

If you aren't reaching set point on the first floor with boiler running continuously, you don't have enough emitters in that area of the house. Room-by-room heat loss calculation and emitter survey needs to be done. Also remember that heat moves upward in multi-story buildings, especially if air can flow freely. Increase emitters on bottom level to counteract this tendency.

EricPeterson

For what it's worth...
I too have a 3-story house, but with CI radiators on all floors, and after splitting this into two zones:

• zone 1: first floor
  
• zone2: second and third floors
  

I found that still the second floor rooms were quite overheated.
So I moved the thermostat to the coldest room (third floor) and added TRVs to all the radiators on the second floor. No need for constant circulation, and all rooms are now comfortable.
A side benefit is that with the TRVs the second floor rooms can be dialed down when not in use with no concern for freezing pipes.
Even if you cannot split into zones the TRVs are a great technology that has worked well for me.

Gordy

As others have said you really need to see where you are at with the heat loss verses the radiation installed.

Sounds like the slant fin isn't enough on the first floor. It's always calling for heat, and the upstairs gets it whether or not it needs it since the tstat is down in that room.

Using trvs is an excellent path for room by room control.

EBEBRATT-Ed

3 section in an old house depending on the construction and the heat loss you may not have enough boiler.

Crank the thermostat and let it run a while and go check the boiler water temperature and see what you get

Also pictures

LI_CJ

Great input everyone, thank you. With respect to the heat loss calcs, I can assure you the kitchen is under-served presently. There's a 10-foot fin-type run that emits almost no heat and the kitchen is large. Another wonderful 'improvement' from prior owner. I will do proper calculations though on all problem areas.

As far as reaching the set point on first floor where t-stat is, keep in mind this system has been compromised so don't analyze this under normal circumstances where fin-type is pumping out heat. The mash up of cast iron and fin-type together results in such poor heat emission from the slant fin (which is in thermostat room).

Everyone's calculation of relative value differs, and I think the reality in my home's situation is that to improve the heating to a grade of A, it will take considerable cost, and I'm not sure how many years you'd need to amortize the up-front expense to come out ahead. I feel like my heating system has a grade of D right now. It's terrible and very frustrating. My goal is to improve this to somewhere in the B- range so that the family is comfortable with the average weather we get in the tri-state area. This is a house that is hot when the temp outside is 95 degrees, and chilly when the outside temp is 5 degrees. But those temperature extremes fall outside of the standard deviation and I'm not trying to solve to that level of temp extreme.

I think step one absolutely has to involve zoning off the first floor from 2/3. I have access to 90% of the basement ceiling, and peaking at the runs to all the 1st floor heating elements, it won't be a huge project to disconnect all of floor 1 from the main heating lines and capping off. The den on the 1st floor was an add on at some point and that has its own zone ( I haven't mentioned this since it's isolated from the problem). I will convert this den zone into the full 1st floor zone (with an experienced tech upgrading the equipment to appropriate sizing).

The other decision I have to make related to the 1st floor is this: Six rooms, 4 have fin-type hydronic, two have cast iron radiators. I need to either covert four rooms to CI BB, or remove the two standing CI rads and replace those with panel rads (like Budderus) that will work with the Slant Fin. I think the simpler and certainly cheaper route is to eliminate all cast iron from first floor and go fin-type.

Step two will involve TRVs as I have heard great results from people incorporating them into their systems.

nicholas bonham-carter

Do a room by room heatloss survey, (which should have been done by the installers for the previous owners), and see whether the radiator output at the loop temperature can meet the needs of each room. This has to be a scientific survey, and not “the room is cold”.
From that information, these problems can be solved, and overcome, and we are here to help.—NBC

HVACNUT

Your system is probably not piped to make a separate zone for each floor. If it is the boiler can be repiped for 3 zones. They also make wireless thermostats.
I'm guessing monoflo. Pics would help.
What brand aquastat is on the boiler and what temperature is it set to? If it's set to 160°, raise it to 180°. If it's at 180°, raise it to 200° max. I would try that as a last resort after checking other things like...
You state some emmiters dont heat. Are there air bleeders on the rads and BB?
Could be the circulator is not correct for the application.
A tech might need to check if the correct orifice is in the burner for the input needed. I think the WBV3 has a max input of 154K BTU.
What's the pressure on the boiler? If the boiler is in the basement the pressure might need to be increased with a 3 story home.
Post some pics from about 6 ft away of the boiler and connected piping. Maybe a rad or two also.

Gordy

Are you sure all the fintube is getting flow? Is it possible it’s air bound?

Or it could be a piping butcher job to a gravity system. Hard to tell with out seeing all the piping.

You could try your own balancing if the radiator valves are functional. Start by throttling down the problematic warm rooms, and see if this gets more flow to the down stairs fintube.

When you said the kitchen fintube zone doesn’t throw much heat something is not right. Flow, air, or piping issues.

It’s a cheap start that takes nothing but time, and patience.

Ironman

You're making the same assumption that the people who hacked up your system did: namely, that the fin tube is sufficient to heat the areas where it was installed. It's most likely not, but that's why an accurate heat loss calc is needed.

You're also assuming that CI rad's and fin tube can operate together from the same SWT. They can't do that satisfactory because the fin tube requires hotter water. If you crank the SWT up to get enough heat from the fin tube, the the CI rad's are gonna overheat - even if they're on a separate zone. It's called the flywheel effect.

A separate SWT zone is possible, but would require extra controls and a separate circ.

Please trust me: these type of old systems are my bread and butter and I run into your scenario regularly. It's always one of two things: either someone's done what you've got or a new owner wants to renovate and make it like yours. I had to talk one out of doing it yesterday. People, including contractors, just assume that any type of modern heat emitter can be connected to these old high mass systems - a fatal error.

Your system is high mass and your emitters need to be high mass. All modern emitters are low mass. You need to get rid of the fin tube and put CI rad's (of the proper size) back in if you ever want to have a balanced system.

As mentioned, a load calc and some good pics would help us to help you.

GBart

I've seen CI radiator systems where some clown put in baseboard in between the piping that used to feed return the radiators, so you had 2ft here, 2ft there of baseboard where the radiators used to be, going from about 100k btu output to about 7k.

You need to do a load calc and then see what your baseboard adds up to, if you don't have the spec's figure about 650 btu/hr per foot of baseboard, yes, I said six hundred and fifty, where a 2 foot section of CI radiator may put out 5-7,000 btu hr or more.

this link is for heat load

http://www.loadcalc.net/

this link for cast iron output estimation, so you can compare what you had

https://www.expressradiant.ca/pdfs/product_classic_sizing_how_to.pdf

EricPeterson

I think you will be sorry if you eliminate the CI from 1st floor and switch all to fin-type. As has been pointed out, fin-type requires hotter temps to work well. We had some once and I hated it, replaced it all with 9" CI BB. Fin-type is noisier heating up / cooling down and does not retain much heat. Of course your wallet will be sorry paying for CI BB so that's not easy either.
At least CI BB is modular and relatively easy to work with. as opposed to trying to lug in some free-standing radiators. But maybe you can find some smaller reasonably priced used rads that will work in your situation - but also as many have said you would want to determine the heating load to see what you really need. Or your work may be in vain.

LI_CJ

Man...I need to have an expert really examine this system as it presently stands. I'm also concerned about the boiler sizing relative to the home's size. Backstory on the boiler - got screwed a few winters ago where my old KV-84 was leaking badly...was middle of winter and needed a replacement. Since I didn't have gas in the house, was forced to install an oil designed boiler.

Subsequent year I had gas run from the street to the house, and we swapped to the Carlin EZgas burner. I'm not cheap but it was a tough nut to rip out a boiler that was less than a year old.

The additional responses to this thread are leading me to believe that this isn't a function of getting the heating system to grade B from D (like I said, I'm at peace if an A can't be achieved), it sounds like we're dealing with a Pass or Fail system.

Thank's for clarifying that getting all of 1st floor to one heating element type isn't really going to solve this problem. I was thinking that if Zone 1 was all fin tube, that was at least better than a mash up of different heating types.

I feel like the best investment here is getting out the fin type and reinstalling CI BB (stand up radiators aren't an option anymore with furniture type and room set up). They money spent to cap off 1st floor from main zone & new piping may come closer in line to just buying the footage of CI BB I need.

Let me throw another variable in - from what I read and with some friends that have gone the Euro Panel route - the thermodynamics of panel seem to fall in the middle of fin tube and cast iron. Although cost not far off from CI BB. Not sure what I'd accomplish though replacing the fin tube with panel. Probably should do it right and go all the way (back) to CI.

hot_rod

Any of the heat emitters mentioned will heat you home to a comfortable condition. When properly sized and installed they will provide a quiet, controllable, efficient system.

The type of heat emitter is really a personal preference, and lot of strong opinions on what type is best

While not typical, I have a mix of floor, ceiling radiant, some fin tube and some salvaged cast iron rads at my place. They can work together to provide a comfortable system. The cast rads are on a radiant slab and run the same supply temperature. While not hot to the touch you can feel the heat energy when you walk by them, and the paint doesn't outgas at low operating temperatures.

I agree that panel rads, while probably the most expensive option, provide an excellent emitter for all the benefits of a wall mounted heating systems. Plenty of choices, easily zoned, ideal for retrofits with pex tube.