40 Year Old Boiler & Home Remodel....Replace or Keep?

AdmiralYoda

@EdTheHeaterMan It tends to make steam pretty quick even after a 5 minute rest. I haven't timed it in a while but its probably 2-3 minutes until it hits the pressure switch and starts all over. If I extend the delay to 10-15 minutes it will run closer to 5 minutes for run time.

Beautiful Ford!

PMJ

AdmiralYoda said:

@EdTheHeaterMan It tends to make steam pretty quick even after a 5 minute rest. I haven't timed it in a while but its probably 2-3 minutes until it hits the pressure switch and starts all over. If I extend the delay to 10-15 minutes it will run closer to 5 minutes for run time.

Beautiful Ford!

I have lots of charted data relating time to steam at radiators from start of burn and off time. For me from cold start it is 20-22 minutes. Consecutive cycles in average weather off times between burns will be 20 minutes and after one of those time to steam at radiators will be about 4 minutes.

So time to steam is directly related to off time because the delivery piping must be reheated first to support steam flow. That time in pressure short cycles I don't have numbers for because I don't do any pressure but it will be very short. It makes no sense to do those. Pressure means you already have more steam out there than needed and firing again right away means you return right back to that place real fast for no good reason unless you like overshooting. @AdmiralYoda's timer is a good way to prevent that.

I will also point out that in open vented systems this time to steam number is also the time all the air has to get out. The shorter those times are the faster the air must move and the more noise it will make. Spacing firings out more reduces that noise a whole lot. Short pressure cycles will be the noisiest these systems can be. So if you don't want air noise you can't allow firings real close together. If your boiler is bigger than needed some sort of timer will be required to do the spacing.

ethicalpaul

If you're going to hold onto the house for more years I'd say keep the boiler just for the fun of seeing how long it goes.

If you're going to sell within 5 years, then replace the boiler so the old boiler doesn't freak out buyers and enjoy having a correctly-sized boiler until then.

And finally, I'm sorry but your boiler isn't 40 years old. The 1980s were about twenty years ago, I remember them fondly!

MikeAmann

ethicalpaul said:

The 1980s were about twenty years ago, I remember them fondly!

I still think so too. If it were only true.

AdmiralYoda

ethicalpaul said:

If you're going to hold onto the house for more years I'd say keep the boiler just for the fun of seeing how long it goes.

That's pretty much the plan. We aren't moving in the near term, maybe 15 years but who knows. I appreciate mechanical things and don't like tossing them if they still work.

But I really do want to see how a properly sized boiler would behave.

ethicalpaul

Then replace it in 13 years (if it lives that long) so you can experience the new boiler for a couple seasons.