Best Of
Re: Re-purposing Monoflo Branch for Radiant Floor Heat
You can run the radiant as a completely independent loop, with its own pump and mixing valve, off of whatever primary manifold you have for the rest of the system.
You might get away with using the two Ts from the abandoned baseboard as the takeoff Ts as well, but you will still need the mixing valve for tempering and an independent pump. Note. Might. I'm not keen on this option…
Re: Efficiency of an indirect water heater
I don't know who compiled that chart. I usually look for independant lab test results.
Be handy to see mod con with indirect.
There are so many variables however, for comparisons like this.
Cycle efficiency tells more of a story. I did a post on calculating that recently.
Cycle Efficiency = total heat output over a period of time ÷ energy content of fuel consumed
Cycle efficiency will always be less than steady state efficiency, calculate it from the run fraction
Run Fraction burner on time ÷ total elapsed time
Mild temperature days with fixed output boilers is where it fall apart.
Using load info RF= heat required ÷ steady state output
A 30,000 load on a 125,000 boiler = .24 or 24%
Using this Brookhaven developed graph, (used with permission) that RF % puts you in the 70% range.
Therein lies the problem with zoned boilers in mild conditions, or less than design load. Which may be 80% of the heating season.
Don't dismiss the importance of modulation, even running out of condensing mode.
hot_rod
Re: Building drain / sewer pipe. Who owns it in NJ?
And that depends on the class of road in Connecticut. Many old town roads that is true. The public (town) will have a right of way — typically 3 rods wide but sometimes 2— centred on the travelled way (and oh does that get interesting sometimes, if the travelled way had moved with time! But if there is an old wall, that will mark the edge), but only for passage. Doesn't provide for utilities, and even paving or improving such a road can get difficult. However, newer roads such as in subdivisions and all State or Federal highways are on deeded rights of way.
Re: Combi boiler recommendation
Most mod/con boilers are pretty similar. Baxi is a really popular brand in the UK, they are a nice boiler. some models use the gas adaptive technology similar to what viessmann has. Here in the US they had a run before combis were accepted and subsequently got labelled as "junk" similar to munchkin. I think they are fairly nice boilers, but are there parts available locally? Not sure if Baxi is made in Canada, my understanding is they are European which is not a bad thing imo, IBC has been gaining a ton of traction though. They make nice boilers, and are readily supplying parts to local distributors, they are also owned by Rheem/intergas so they have a proven distribution network. never heard of confronto. Personally I would lean towards the IBC, and ask the guy where he gets parts from, because you want something supported as locally as possible, even the best boiler has a bad day, so better to just have a bad day than a bad week.
GGross
Re: Radiator slow drip at the union of the shutoff valve
That drip is enough to account for most, if not all, of your water loss. Surprising how they add up.
Now. A quick review of how a union works. The actual seal is on a pair of mating surfaces behind that big nut. The two surfaces — one on the valve and one on the pipe (called a spud) coming out of the radiator — must mate very exactly to prevent a leak.
So. What you need to do is first turn off the valve. You don't want to get steam all over the place! Then loosen that big nut. If you imagine yourself sitting on the radiator, it will unscrew counterclockwise. If possible, use a big crescent wrench, not a pipe wrench, to avoid scarring it. It should unscrew completely and be caught on the spud. Now the fun part. You need to separate the spud from the valve, so you can clean the two mating surfaces. Whatever works. Clean the surfaces with something like the rough side of a dish sponge — never ever use sandpaper or anything abrasive! When you're happy and the surfaces are bright and shiny, push the radiator over so they are firmly seated. A union will not take up lateral or angular alignment problems, so make sure that the final alignment is perfect. Then hand tighten the unit nut and give it no more than a half turn more.
Good luck!
Re: Mod/con boiler - is exhaust vent noisy?
As stated in my original post, I am replacing both with a boiler and indirect water tank. :)
Re: It's freezing upstairs
I can vouch that Ed is definitely a friendly, helpful, dare I say lovable guy! He has given excellent free advice and is just wondering why you aren't taking it. It's OK to be cautious. But if you or someone else doesn't open that orange valve, your problem is not going to get fixed.
jesmed1
Efficiency of an indirect water heater
Probably isn't anywhere near what many assume. AI seems to way off with their prediction of 99% :)
A coil in a tank of still water is not such a great heat transfer mechanism. Certainly not 90% boiler efficiency even if you have a massive or duals coil indirect for the boiler to feed.
I'd guess not much better than a boiler with a tankless coil, when there is no circulation.
The heat transfer number is not so easy to pin down with so many variables.
EK has it right using a separate flat plate, leveraging two moving, turbulent flows with a lot of surface area.
With close approach sizing of a plate HX you could generate 120 DHW with 125° SWT to the plate HX. So now you could leverage the mod con 90% efficiency. But still the crappy heat exchange inside the tank. A dhw recirc pump would change the transfer efficiency.
Condensing tankless WH would be a higher transfer efficiency moving turbulent flow again.
And of course the near 100% efficient electric tank water heater. Better yet a properly applied HPWH.
Nothing against indirect tanks, but the hype may be overlooking the thermodynamics.
Then there is the pie in the sky standby loss numbers. An indirect tank at 120F in a room at 80F skews those numbers. Put the indirect next to the combustion air grill and see how that less than 1° per hour works out. Ive been in boiler rooms with snow drifts below the combustion air grills.
hot_rod
Re: Mod/con boiler - is exhaust vent noisy?
Duravent sells flexible venting that can be dropped down the chimney, and a kit that comes with a chimney cap, and the transition pieces to get to and from rigid polypropylene vent pipe. I would go that route, the poly vent pipe is a bit more expensive than PVC, but it is actually rated for the flue gas, and the flexible stuff is much easier to drop down a chimney in one solid piece, you can just use PVC for the intake.
GGross