transformer capacity

[Deleted User]

I would put an Argo controller on this system. It takes all of those zone valves, thermostats, transformers, and puts it in a box with indicator lights. It will show which zone is calling for heat, when the end switch makes contact, and then start the boiler. You can also set one zone as a priority zone, it gets heat and is satisfied before all the others. It is a real neat little gizmo that eleiminates bad connections, and makes trouble shooting a breeze..

Pension Lover

renegade zone valves

I have a natural gas, hot water baseboard system. There's 349 linear feet of baseboard, one B&G series 100 circulator, 5 zones, each with honeywell zone valve. The distance between the boiler and the uppermost run in the house is 35 vertical feet. There are two 24 volt transformers hooked together (wired in series?) that provide power to the 5 zone valves (Honeywell V8043F)and an aquastat relay (Honeywell L8148E).

Last night before falling off to sleep, I did some light reading about honeywell zone valves, aquastats and transformers. Somewhere in there, I think I read that a 24 volt transformer is designed to power no more than two zone valves.

I was inspired to research because, during the course of the day yesterday, the thermostat for zone #2 called for 67 degrees from morning till night, but that zone never reached 67 degrees. It stayed at 60 degrees till early afternoon and gradually crept up to 64 degrees just in time for me to go to bed . . . whereupon the thermostat shifts to night time mode and starts calling for 60 degrees.

I have a comfortable chair down in the boiler room, so I can sit and stare at the conflagration of pipes and valves while I will it all to make sense.

During my stay in the boiler room yesterday afternoon, I noticed that the valve to zone #2 was closed and the circulator was off. I also noticed that zone #3 was open (I could tell by the manual switch lever at the back) . . . and this, with the circulator off. (I don't think either of those things are supposed to happen.) No other zone valves were open at that moment. But, when zone 1,4 or 5 called for heat, the valve would open and the circulator would trun on. When zone 1,4 or 5 was satisfied, the circulator would stop and the valve would close. In the meantime, the #3 zone valve remained open throughout.

Today I went down to the boiler room and discovered that zone valve #3 was closed. At that same time, the circulator was running because two other zones were calling for heat. Also today, zone #2's call for 67 degrees was almost satisfied but fell short and only reached 66 degrees. The outdoor temp has ranged from a high of 45 degrees F to a low of 33 degrees F.

One day the zone valves are behaving badly, and the next, it looks like they are doing what they are supposed to. This sounds like a problem to me. What is causing these variations?

Thanks in advance to anybody who can diagnose this problem. Don't hesitate to ask for more information if needed . . . I've got plenty of that stuff . . . it's you guys who know how to apply it.

Wethead7

transformers??

I hope you mean wired in parrallel not in seires?? We need the make of the zove valves, the age, model, & amp draw. The problem may be a bad heat motos on number three zone valve. But with out the aditional information, I would be guessing. You mwant to up grade to a zone controller and or outdoor reset. These should reduce your fuel bills.

Steve Eayrs

I would assume the VA of your transformers are either 40 or 50. Two common sizes. If so and they are wired right, they should be enough for your 5 zones.

Also, I would check zone valve # 3 to see if it is opening up far enough to kick in the end switch. The end switch on your honeywell zone valves, is a switch that makes contact when you zone valve opens, which in turn is what turns your pump on. Most likely through a relay, or aquastat w/ builtin pump relay. If you take the cover off the zone valve you will see a lever that swings around, and when operating properly, should push in a little button (end switch). If it doesn't swing far enough, you most likely need to replace the zone vlv head.

Steve

Dale

Time

Since time doesn't seem to be an issue for you why not get 10 , 24 volt test lights and put them on the zone valve motors and switches, you could watch the zone valve get powered and then the end switch make, would take alot of the guess out of the electrical timing. Also yes the tfmr's if there are two can be in parallel to get more VA or a simpler and better way is to just have them power separate valves. try taking a wire off one tfmr at a time and see if some of the valves have no power to them when the zone stat closes, if all still have power you are in parallel, if some don't it is set up as a separate supply.

Duncan_6

Troubleshooting

Typically, each room thermostat will operate the boiler independently from the others.

The zone valve has two parts, a motor to open the valve(yellow wires) and an end switch to operate a boiler circuit(red wires).

Your room thermostat is an on/off switch that turns on (opens) the zone valve motors only. An external transformer is the electrical power source for the zone valves. The zone valve motor is the electrical load.

When the a zone valve opens fully, it closes a simple on/off zone valve end switch mounted in the valve assembly mentioned by others above (red wires off the valve). You could say these zone valve end switches turn the boiler circuit on or off.

The on/off zone valve end switch completes a circuit to a boiler relay and transformer mounted in the boiler. You can hear the boiler relay click when it's energized.

This boiler relay usually has a separate 24 volt transformer on the boiler as a power source. This boiler relay typically closes two sets of contacts, a 24 volt circuit to the gas valve and a 120 volt circuit to the boiler circulator.

Honeywell zone valves draw about 8 VA. So a 40 VA transformer should be able to power 5 zone valves of this type. I don't know why your system has two external transformers.

If the transformer(s) is (are) undersized for the total load, zone valves could operate either erratically or not at all.

From your description, it sounds like zone 3 is the only one with the problem. I agree it sounds like a zone valve end switch problem if the valve opens but the boiler/circulator don't operate.

But the zone valve end switch could also not be operating because the valve isn't opening fully, or not opening at all. Or it could be a loose wiring connection. Or it could be a wiring problem associated with the "extra" transformer and zone 3.

Hard to tell from here. Got a SYSTEM wiring diagram? (Not the boiler wiring diagram)