Dario
New Member
What is the best gas cast iron hot water boiler with no domestic coil And going to use a chimmy with a liner installed. I have weil mclien oil cast iron now going to rip out this summer.thanks
A little bit more info on my home 1 floor ranch 1,675.00 sq ft 150 ft of fin tube argo baseboard. All new windows in house house is well insulated Chimney will just need a good stainless steel insulated liner for future for boiler . You guys are spot on my wgo oil now is way oversized. And boiler only runs in the winter for heat house has a gas water heater 40 gal bradford white . both water heater and oil boiler are 22 years old .thank you
If i go with the cga25 do i need a insulated chimney liner or no ? I would like to stay with weil mcStainless steel liners are quite expensive compared to the plastic venting used by condensing equipment.
If the 150' of baseboard is all one zone you have PLENTY of baseboard for running a condensing boiler. Even at low condensing temps sufficient for low to mid-90s efficiency (~125F out, 115F return) that's enough baseboard to emit ~30,000 BTU/hr (~200BTU/hr per running foot), which is probably more than the load at your 99% outside design temp (about +17F in the Philly area- yes I know it gets a lot colder than that.)
A tight well insulated house that size with l0w-E windows is likely to have a design load of only ~20-22,000 BTU/hr, and wouldn't need a boiler with more than ~30,000 BTU/hr to be able cover even polar vortex disturbance cold-snaps. The smallest commonly used cast iron boilers are probably still too big- the W-M CGa-25 has a DOE output of 44K (~2x the likely load), the Burnham 202e is good for 32,000 BTU/hr, which would be better (if your actual load is that low, which is why you should run a fuel-use load calc.)
Given the 150' of baseboard with a cast iron boiler you'd need to oversize it or design in a boiler bypass for a right-sized boiler. Without well designed & implemented bypass plumbing need something like 50K+ of DOE output to avoid chronic destructive condensation inside the boiler, which is getting into ridiculous-oversizing territory (which is at least better than LUDICROUS oversizing! )
An 80,000 BTU/hr modulating condensing boiler with a 10:1 turn down is probably the best bet, something like a Navien NHB-80, or an HTP UFT-080W, (either of which can modulate down to ~7500 BTU/hr) or even a combi-boiler that can throttle back to the <22,000 BTU/hr range if a tankless water heater is appealing to you as a replacement for the B-W. There are others, but either of those two are likely to have a lower installed cost than a mid-efficiency cast-iron boiler with a new stainless flue liner.
Stainless steel liners are quite expensive compared to the plastic venting used by condensing equipment.
If the 150' of baseboard is all one zone you have PLENTY of baseboard for running a condensing boiler. Even at low condensing temps sufficient for low to mid-90s efficiency (~125F out, 115F return) that's enough baseboard to emit ~30,000 BTU/hr (~200BTU/hr per running foot), which is probably more than the load at your 99% outside design temp (about +17F in the Philly area- yes I know it gets a lot colder than that.)
A tight well insulated house that size with l0w-E windows is likely to have a design load of only ~20-22,000 BTU/hr, and wouldn't need a boiler with more than ~30,000 BTU/hr to be able cover even polar vortex disturbance cold-snaps. The smallest commonly used cast iron boilers are probably still too big- the W-M CGa-25 has a DOE output of 44K (~2x the likely load), the Burnham 202e is good for 32,000 BTU/hr, which would be better (if your actual load is that low, which is why you should run a fuel-use load calc.)
Given the 150' of baseboard with a cast iron boiler you'd need to oversize it or design in a boiler bypass for a right-sized boiler. Without well designed & implemented bypass plumbing need something like 50K+ of DOE output to avoid chronic destructive condensation inside the boiler, which is getting into ridiculous-oversizing territory (which is at least better than LUDICROUS oversizing! )
An 80,000 BTU/hr modulating condensing boiler with a 10:1 turn down is probably the best bet, something like a Navien NHB-80, or an HTP UFT-080W, (either of which can modulate down to ~7500 BTU/hr) or even a combi-boiler that can throttle back to the <22,000 BTU/hr range if a tankless water heater is appealing to you as a replacement for the B-W. There are others, but either of those two are likely to have a lower installed cost than a mid-efficiency cast-iron boiler with a new stainless flue liner.
If i go with the cga25 do i need a insulated chimney liner or no ? I would like to stay with weil mc
This is awkward, but...
It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.
If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.