Can I figure what type was the original system?

DJDrew

We live in a 1938 house with radiators half-inset into the wall. A year and half ago, we had a new hot water boiler installed and in the process relocated the former boiler, installed in 1992, from sitting in the middle of the room to a side wall.

We were talking about the history of the house and the changes that have taken place since it was built in 1938... the coal room is no longer a coal room, the well room is no longer a well room, the basement fireplace built for burning garbage is now for ambiance, some idiot took the original slate roof off and put a shingle one on, etc. A question came up about the original heating system... was it two-pipe steam or gravity hot-water? The guy who installed our new boiler thought it might have been steam based on the black sludge, but admitted he was no expert on anything but forced hot water systems.

Would there be any clues I can look for based on some of the original piping and/or radiators? Attached is what the original piping looked like before we relocated everything to the wall (I should have taken more). All the radiators have a plug/screw midway up. The original pipes are pitched perfectly and get smaller the further you get from the boiler and at the end of the main lines are pipe nipples installed that do not look original to the other piping.

Really just curios if anyone has any thoughts or clues I can look for to determine the original system type.

Steamhead

Are the supply and return mains and radiator connections the same size, or is the return smaller?

STEVEusaPA

I doubt it was ever steam, but a picture of one of your radiators could tell a better story.

Side note: your water heater is too close to the electric panel and violates code.

Danny Scully

I would think it was gravity, but pictures of the radiators would help, and more of the system piping.

DJDrew

@Steamhead I just went and measured, the supply and return mains are the same size.The branch lines to each radiator are a smaller size than the mains, but identical.

@STEVEusaPA Attached is a picture from when we were redoing a room. Also, yes, I always thought it was a little close for comfort, not sure why they were installed so close... more stories of the unknown. The hot water tank has a date older than the inspection sticker from when the panel was replaced!

HVACNUT

Looks like it was gravity water.
Any pics of the new boiler?
I see the wife is working away and you're snapping pictures.
What a country. 😁

DJDrew

@HVACNUT Thanks! It's interesting seeing the systems of the past and trying to figure out the original design and intent.

Yes, attached is a pic after the install. Much smaller than the one it replaced. I had a thread earlier about an issue I noticed once it was installed, which has more pictures.

Solid_Fuel_Man

Nice clean looking install, but it sure is hard for some guys to put that circulator where it belongs!

The large diameter piping indicates a gravity water system from what I see. Meaning the circulator on the return really isn't as much of a problem due to low head of the large old piping.

HVACNUT

That water heater really needs to be moved to the other side of the boiler.

Solid_Fuel_Man

Hard to tell from the pic but that sure looks like yellow Romex zip tied to the pipe feeding the boiler.

Also looks like by the new press connections that water heater was repiped wonder why it wasn't moved to the other side of the boiler giving proper clearance to the panel.

DJDrew

So it's a plumbers lament I suppose. The reason the hot water tank is not on the other side is because where the broom is in the photo is the edge of the firebox for the basement fireplace. Those solid panels on the wall in between the fireplace and the new boiler are chimney clean outs.

We are in the process of building a wall in between the fireplace and the new boiler. Once that is done, we can probably relocate the hot water tank out into the room along the new wall. If we do that, we'd probably want to tweak the location of the expansion tank and maybe at the same time have the circulator flipped to the supply side.

@Solid_Fuel_Man Thanks, the gravity system would certainly make sense. You are very observant, that was Romex zip tied to the return piping. I didn't like the way the installer had left that zip tied, so I removed it and ran the cable along the block wall after he left.

flat_twin

Is your house in a rural area or in a town? I ask because if electricity was available when your house was built, it may well have been a pumped hot water system from the start. Around here towns and villages had electricity by the late 1920's. Areas outside of town had to wait until rural cooperatives were organized several years later.
I had the same questions about our hot water radiator system. Was it ever a gravity system? I knew it was coal fired at one time. Evidence of a coal bin in one corner of the basement remained. The original big boiler was still there and working when my parents bought the house in 1966 though it was a fuel oil conversion.
When I asked about it here on this forum, they said to look for any signs of an expansion tank in the attic. There were none. Also the largest send and return piping was 3 1/2" diameter, gravity systems were often larger piping.
With no attic expansion tank or evidence of one and the fact that this heating system was installed after electricity was available in this small town, I came to the conclusion that this had always been a pumped system. In researching the home, I found out the people who owned it during this time (late 1930's) were fairly well to do and had the means to install an expensive central heating system. Weil Mclain boiler and 10 radiators, similar to yours but with six vertical tubes per radiator section.

Big Ed_4

I really don't see the need of pumping away on such a massive system . All the air will collect and will be bleed out through the radiators . The air scoop will be useless . Out door reset ? Debatable with a proper size boiler ... Am I wrong ?

Yes I would pump away , but is there any benefit on a massive system with large supply pipes and radiators ?

brandonf

Your electrician must shake his head when he walks in the basement. I will never understand why so many people stack a bunch of stuff in front of the panel. If your power goes out you're going to be fighting all that stuff in the dark. 🤣

Steamhead

Big Ed_4 said:

I really don't see the need of pumping away on such a massive system . All the air will collect and will be bleed out through the radiators . The air scoop will be useless . Out door reset ? Debatable with a proper size boiler ... Am I wrong ?

Yes I would pump away , but is there any benefit on a massive system with large supply pipes and radiators ?

Sure there is. My system is converted gravity, and with a right-sized circ, air separator and pumping away, I almost never have to touch any bleeders. Before, there were two radiators that were always accumulating air.

Solid_Fuel_Man

What? @Steamhead has a converted gravity system? You mean you have a circulator? Didnt convert to STEAM?

HomerJSmith

Where's your earthquake strapping on the W/H. Where is the air venting on your radiators? Why would you need a bypass on the inlet and outlet of the boiler if the boiler runs at 180 deg.? Is your return water less than 130 deg.? How are you regulating the temperature in each radiator? That is probably a low loss heat exchanger ? in that boiler and you are pumping into the X tank instead of away from it regardless of the size of your headers.
Air scoops are cheap but takes a long time to remove the air out of the water. A micro bubbler would have been a better choice.

I would consider a Caleffi Dirt Mag on an old iron system.

DJDrew

@flat_twin Thanks! Our house was probably considered "rural" when it was built, but it certainly had electricity from day one. Now it is in the heart of suburbia. The heating system you describe seems very similar to ours.

@HomerJSmith I just saw an Ask This Old House episode on earthquake proofing a house and learned of those straps. The bypass was needed on the boiler to prevent thermal shock and to allow the boiler to operate at non-condensing temperatures. That said, there is a whole other thread on the boiler's temperature. Essentially, it will run for an hour or more on 5 degree days and still only get the system water temperature up to 135 degrees -- and on 25-30 degree days, it'll run for 45-50 minutes and maybe get the water temp up to 130 degrees. Our house is probably way over radiated, and with the amount of water in the system, it never gets up to high temperatures before the thermostat is satisfied. This does mean the heating system has a slow response time and getting all the radiators balanced to heat up equally has been a little bit of a challenge so the hot water makes it to the further rads.

In general the over-radiation is great, aside from an add-on bathroom that had CI baseboard installed to match the heat-loss. Since that room is the only one not over-radiated, it's super chilly despite being well insulated. We are thinking of some solutions when it gets redone, but I'll start another thread on that when we get closer to jumping in on that project.

Steamhead

Solid_Fuel_Man said:

What? @Steamhead has a converted gravity system? You mean you have a circulator? Didnt convert to STEAM?

Don't have the time- and besides, that was one of the systems I experimented with that resulted in this:

https://heatinghelp.com/systems-help-center/sizing-circulators-for-old-gravity-hot-water-heating-systems/

DJDrew

Steamhead said:

Solid_Fuel_Man said:

What? @Steamhead has a converted gravity system? You mean you have a circulator? Didnt convert to STEAM?

Don't have the time- and besides, that was one of the systems I experimented with that resulted in this:

https://heatinghelp.com/systems-help-center/sizing-circulators-for-old-gravity-hot-water-heating-systems/

@Steamhead That article was very helpful!! We have an EDR ~950 and a Taco 007-F5 that came prepackaged with the boiler. Seems to be an okay match if I am reading the chart correctly.