In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
For those that are interested be cautious about disconnecting any ground wires on water piping.
To make it simple, most that post here have probably looked inside their electrical panel at some point. You may have noticed the "neutral bar" this is where all your white (neutral) wires terminate Including the white neutral coming in from the POCO, also any equipment ground wires (green or bare) and also the "grounding electrode conductor" that's the bare wire going to your metal water pipe or well casing or ground rods.
I ran into a job where a plumber called me, he was trying to solder and the valves in the house wouldn't hold tight (even the main) so he loosened the nut on the water meter to let the water drip out so he could solder. He saw an arc and got knocked on his butt. He was so scared he wouldn't go back in the house
The problem was out at the transformer on the pole a loose neutral wire (open neutral). Look at a transformer mounted on a pole, there is always a ground wire from the transformer down the pole to earth.
When the neutral is loose or open the power is going to find it's way back to the transformer somehow. Since it can't get back through the neutral it goes through the neutral bar to bare wire to the water pipe to earth, through the earth to the transformer ground rod and up the pole to the transformer.
I put my amprobe around the water pipe and read 5 amps.
But it gets better.
Even if all the wiring in you house is perfect and the power to your house is SHUT OFF you may have power flowing through your water pipe, If your neighbor has a loose neutral and your house is closer to the transformer
Consider this analogy:
A steam heating system maintaining temperature is like a hot air balloon maintaining altitude. If both systems have a modulating flame then it is possible to change the flame to suit the conditions and maintain the temperature or altitiude quite close to the desired setpoint. Unfortunately, most of us have a one speed flame.
A hot air balloon with a one speed flame will rise when its flame is on and will fall when it is off. The longer the burn times the higher above the desired altitude it will rise and so necessarily the longer the off times will be while it falls back down. If you choose to have more shorter burns closer together you can operate the balloon always much closer to the desired altitude.
Our steam systems are the same. Our boilers cannot be the right size on an average day. A boiler that will heat the place on design day is at least 2 times too big on an average day. With a one speed flame there is simply no getting around this fact. So our only choice now becomes how long to run the flame. Just as with the hot air balloon, longer burns means higher rises above the setpoint and longer waits for the temperature to fall back down. In my view any burn allowed to run to a pressure stop in these systems is a burn that is already way too long for the conditions.
Any 75-100 year old steam system was designed with extra radiation and it was intended to be operated with that radiation never full. They were operated with single digit ounces of pressure at the coal fired header and at zero or even mildly below atmospheric in the radiators. Pressurizing these systems to the point where traps close at all or vaporstats trip is proof that way more steam is in the system than is required to match the heat loss and you are now surely rising considerably above the temperature setpoint just like the hot air balloon gaining altitude.
I have found any pressure at all to be the enemy. Uncomfortable and wasteful. It causes much bigger swings in the temperature of the radiators and therefore the rooms too. It really doesn't take that many more cycles to totally eliminate it. In 2 pipe when you add natural vacuum to that it gets amazingly better yet. I am convinced that the operation of these systems in a way so unlike the original intent has only hastened the demise of residential steam by making it far less comfortable than it could be. After what I have experienced with my 2 pipe I would never consider going back to a pressure based control.
Oops...when I saved draft and came back I, pics were gone..mad dog
The raison de etre to check relief valves: Main reason why relief valves need to stand up straight, too ! Not only was the nipple, elbow and valve itself, 100% clogged, but so was the pig tail assembly. The ONLY thing preventing this "BOMB" from going off was a working probe l.w.co.! The HO said the original.oil-to-gas conversion installer told him it was maintenance free! Oy veigh! Mad Dog
I got a look at a plate HX from a residential application in the Bozeman area this week.
A new boiler installation, DHW problems less than a year into the start up. Troubleshooter checked pump operation, sensors, control, replaced the control board, per the manufacturers suggestion.
Finally took the HX apart to find the boiler side had fouled. Some of the particles that Dale shook out measured .030. the boiler fill water was from the site, well water, one fill and flush.
We don't often think about the A side on these combo plate heat exchangers, or how hard or high TDS water can compromise them from day one. Same scaling potential inside the boiler I suspect. An expensive troubleshoot and repair!
Here is a graph we put together to show how efficiency and performance drops as scaling accumulates.
Interesting how simple the HX to composite block connection is made with flat washers.
a I've tried to get someone down here to stock them or have any interest in ordering them, but it just isn't happening, wish I could.
We recently moved our business to a small town and the battle of getting material down here is a big one.
Since the relief valve is a major safety device, yes I test them. The only time I don't is if the customer declines to have it tested.
As technicians we are responsible for ensuring safe operation of the equipment. If the valve fails after you service the boiler wouldn't you feel responsible?
If you aren't testing your guessing. And guessing isn't professional.
NY_Rob, nice work! I think the way I interpret this data is that you reduced your usage by what appears to be a solid 25%, assuming the average neighbors didn't change their habits too much. Moving from average to just outside the top 20% with an older house is impressive. That's the difference between making the playoffs and watching the playoffs from home.
This is an interesting data point on real world vs. AFUE ratings and whether a cast iron boiler's AFUE should be compared directly to a mod-con's AFUE. I assume your old cast iron boiler had an AFUE of ~80%. Since your savings are ~25% when a 95% AFUE rated boiler replaces the old one, this data suggests that the 80% AFUE rating was unrealistically high and this measure doesn't seem to reflect as-installed reality consistently for cast-iron boilers, due to some combination of oversizing, performance degradation, etc.