Birds nest

GW

I sooo love the classic nest. This is above the boiler we replaced today. Of course I clipped the zip ties and Re zipped when I was done. The budget called for a new boiler only. The basic slip in. The only thing that required expertise was jockeying the gas line and figuring out the nest. The new boiler reconnected to circ flange and we chopped in a union on the supply riser

So, 3 HW zone valves, previously installed. Two heat and one indirect. The Two warm air AHU units, out of site and Two ac units have their control wiring in this nest too.

The original installer has the common wire on the two ac’s tied to the common Yellow on the zone valves.

Anyway, here’s to you Mr Low Voltage Control Guy

Steamhead

That looks worse than me on a bad hair day............

BobC

At least you still have hair!

Bob

GW

yes it's not the worse control wiring ever, but if i didn't understand low voltage, this boiler job would have had me in serious damage control. The AHU's power the two heating zone valves. We installed a new 24v trans to cover the indirect zone valve. Heating guys---if you're shaky on control wiring, be on the lookout!

CTOilHeat

It's worse when they wrap it into a giant ball of wires and zip ties. Or worse...electrical tape.

JUGHNE

Most of my zones are powered by a 75VA transformer.
However 2 zones share the AC control and those are powered by the AHU transformers. I did not want 2 sources of 24 VAC at the tstats. (I know a senior moment may occur someday)
The end switches of the zone valves (being dry contacts) use the heating 75VA power to do pump & boiler call.

I have labeled the AHU of such as I have shut the AHU power off and spun my wheels searching as to why the heat does not work. ( I guess the senior moment has already been here).

HVACNUT

Like @JUGHNE, we use 1 power source at the thermostat, but install an isolation relay in the A/H for the heat circuit. But thats on new construction and wiring can be run wherever.
I mess like that ^ your stuck with someone else's mess. You did right and labeled everything.

Solid_Fuel_Man

Honestly, that's my biggest pet peeve with zone valves (which I prefer over circulator zoning if heads work out). Seems half the jobs I do pig-tailed actuators are delivered. Take even the old gold series heat motor Taco's allowed you to connect your own wires so you do t habe to have umpteen flying splices for all to see. Then the rats nest can be at least moved into a box with labels.

Rant: seems the valve actuators are a few bucks more with terminal connections vs. pigtails so I'm sure that's what drives the specifiers to order them and our wholesalers to stock them.

mikeg2015

There's a small, but completely untapped market for boiler control panels including terminal blocks or even better, preassembled wiring harnesses. Could easily have indicator lights, switches for "auto/test/off". Include isolation relays, plug in zone panels, ODR... Lots of potential there.

the inside of my control panel is a next. I'm ashamed. I used the wrong wire for most of it.

GW

Yes took me an hour to figure it out. What a pain.

I happen to prefer the pig tails.

A pre wired control? How would that work? Often times our zone valves are spread out a bit

Grallert

That was my pet peeve GW. Valves and actuators spread all over the building, tight up in the floor joists. Man that drove me crazy.

GW

We all have our issues. Mine are multiple and redundant piping running parallel. Obviously it’s needed but sometimes it seems like a waste of energy.