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Taco ZVC403 issue?

Xmytruck
Xmytruck Member Posts: 85
edited December 2014 in THE MAIN WALL
Hello
Notice today one of the zones in my house was cold so I went to check the tstat and it was calling for heat. Went to my heating unit Navien CH240 and noticed that the taco was light up for tstat call but the value light was not light up . CH240 was not really running but the pipes from both zones where hot. I noticed that the baseboard on the zone one starting heat up. But the light for zone one never went to red for value open.Second floor value opens and the unit fires up. I am assuming that zone value one is stuck open and I am getting heat only when the second zone value is open or is it possible for the led to be burnt out?
thx
Xmytruck

Comments

  • kcopp
    kcopp Member Posts: 4,431
    Taco ZV? What type of T-stat? may be the anticipator has to be adjusted. Or the zv end switch is broken
  • Xmytruck
    Xmytruck Member Posts: 85
    The Tstat are honeywell they are electronic not sure on the model number, the other day I did smell something in the basement that smelt like plastic burning. Could that be the ZV switch burning up?
  • Xmytruck
    Xmytruck Member Posts: 85
    Just measured the voltage to the values zone two the one that is working is getting 24.5 between the green and red. Zone one that I think is not working is getting 10.5 volts between red and green but red and white is getting 24.3. So can I assume that I have a bad value.
  • kcopp
    kcopp Member Posts: 4,431
    What zone valve?
  • j a_2
    j a_2 Member Posts: 1,801
    its possible the bad valve is drawing to much…Its possible the head is seized…Is the override hard to move to the open position….
  • Eric_32
    Eric_32 Member Posts: 267
    Power it down and swap zone valve heads. If the problem moves with the head you know what you have to do.
  • Tom_133
    Tom_133 Member Posts: 884
    Most likely bad end switch on zone valve if you are using them. Meaning if the zone valve has 4 wires and you are using all of them then two wires open the motor and the other two light the valve light on taco box and tell the boiler to fire. Sounds like you have a bad end switch, I would open green box and jump 3 and 4 on the bottom of the panel on the zone that corresponds with the one that isn't working to test the theory
    Tom
    Montpelier Vt
  • Xmytruck
    Xmytruck Member Posts: 85
    The override is hard to move and it hot to the touch compared to the one that is working. The value is only two years old is this common for it to go bad?
  • icesailor
    icesailor Member Posts: 7,265
    Xmytruck said:

    The override is hard to move and it hot to the touch compared to the one that is working. The value is only two years old is this common for it to go bad?

    If the ZV is a Taco Wax Motor 572 type with the manual handle on the side by the wire terminal board, it should not he hard to push/pull the lever down. Spray some WD-40, 556 or Kroil into the slot on the power head. Operate the lever. It should get easier. Remove power to the valve by removing the top (#1) wire for a minimum of 2 minutes. I wait for three. DO NOT REMOVE THE POWERHEAD BEFORE YOU REMOVER THE POWER FROM THE VALVE!!!! Take the power head and look at the black metal plate that the valve connects to. There will be a brass post in the middle. If there is any rust build up around the post, it will cause resistance that the valve motor will have to overcome. Spray liberally with penetrating oil. Take a large pair of water pump pliers, and with one jaw on the bottom, the other one on the top of the brass piston on the top, operate the piston with the pliers. If it is hard to push down , keep at it. If it gets easier, the piston is sticking in the rust on the plate. When the piston is down, slather it with Never-Seize. Before you finish, check to see if all 4 steel screws that hold the plate in place can be removed without breaking. Put the valve head on and connect the wires. Close the thermostat. If after three minutes the red light doesn't come on the ZVC, the power head is bad.

    Out of the box when newly installed, the 572 type valve will hurt your finger if you try to manually operate the valve. Spray it and it easily operates. Sometimes, the resistance is so bad, it will bend the lever and you don't know that the valve didn't open. If you drain houses for the winter, and one valve doesn't open, you can have an expensive pipe repair on your nickel.

    If you can get the 4 screws out of the top, it is easy to replace the whole valve without removing the valve body. Which can take hours because of trapped water and usually a difficult location.
  • Xmytruck
    Xmytruck Member Posts: 85
    icesailor said:

    Xmytruck said:

    The override is hard to move and it hot to the touch compared to the one that is working. The value is only two years old is this common for it to go bad?

    If the ZV is a Taco Wax Motor 572 type with the manual handle on the side by the wire terminal board, it should not he hard to push/pull the lever down. Spray some WD-40, 556 or Kroil into the slot on the power head. Operate the lever. It should get easier. Remove power to the valve by removing the top (#1) wire for a minimum of 2 minutes. I wait for three. DO NOT REMOVE THE POWERHEAD BEFORE YOU REMOVER THE POWER FROM THE VALVE!!!! Take the power head and look at the black metal plate that the valve connects to. There will be a brass post in the middle. If there is any rust build up around the post, it will cause resistance that the valve motor will have to overcome. Spray liberally with penetrating oil. Take a large pair of water pump pliers, and with one jaw on the bottom, the other one on the top of the brass piston on the top, operate the piston with the pliers. If it is hard to push down , keep at it. If it gets easier, the piston is sticking in the rust on the plate. When the piston is down, slather it with Never-Seize. Before you finish, check to see if all 4 steel screws that hold the plate in place can be removed without breaking. Put the valve head on and connect the wires. Close the thermostat. If after three minutes the red light doesn't come on the ZVC, the power head is bad.

    Out of the box when newly installed, the 572 type valve will hurt your finger if you try to manually operate the valve. Spray it and it easily operates. Sometimes, the resistance is so bad, it will bend the lever and you don't know that the valve didn't open. If you drain houses for the winter, and one valve doesn't open, you can have an expensive pipe repair on your nickel.

    If you can get the 4 screws out of the top, it is easy to replace the whole valve without removing the valve body. Which can take hours because of trapped water and usually a difficult location.

    Hello
    When you mentioned draining the house I am do you mean to winterize the house if I was not using for the season?
    Thx
  • Xmytruck
    Xmytruck Member Posts: 85
    edited December 2014
    Hello
    So this morning I go check on the system this morning and both lights are on :s ... I used the override a few times perhaps that got it unstuck or was there air in the system? Navien are self filling so could it be possible it fill the loop with water last night? When zone one came on the light did flicker then stay on. Not sure if the value is on it's way out.

    Thx
    Xmytruck
  • icesailor
    icesailor Member Posts: 7,265
    "" Hello
    When you mentioned draining the house I am do you mean to winterize the house if I was not using for the season?
    Thx ""

    Yes. The houses were completely drained of any water, and no heat.

    Insurance companies are getting very touchy about paying water damage claim in unattended houses. Unless you are paying someone to regularly check the property (and that doesn't mean driving by once a week) and actually have proof of entry, log book records, and proof of insurance, they can be blamed or the claim can be denied. And they "Pro-Rate" the equipment. A broken 20 year old boiler might cost $20,000 to replace but they give you $500 towards the replacement.
  • icesailor
    icesailor Member Posts: 7,265
    Did you lubricate the lever like I suggested? Does it move much easier than before? Does it move as easy as the other one? Did you lube the other one too? Just spraying them, you will notice a marked difference in the effort required to move the manual lever.

    When the red light doesn't comes on, it usually means that the motor is bad and not pushing the piston down far enough to make the #2 contact which closes TT and makes the red light come on. Unless it is binding in the bore.

    If they are Taco 572'a, when the "good" one is calling, pull the lever down. It should go all the way to the bottom. Then make the other one call. The lever should go to the same place. If not, you might need a new power head. If you need a new power head, and the plate has rust in the middle, it is cheaper to buy a new complete valve, use the new power head, and replace the actuator that is leaking. If that is the case, post back. I will tell you how to easily do it without replacing the valve body. Which can be an extreme and upsetting chore.
  • Joe Mattiello
    Joe Mattiello Member Posts: 705
    I read all the comments and am very impressed with all the information available on the Taco control. Even more impressive is the eagerness to share your knowledge to help someone having problems; that's cool!!
    As for troubleshooting the control, and or valve. I always try to isolate the components to better determine which component is faulty. Placing a jumper across the thermostat terminals to validate a demand is a good place to start. that should limit troubleshooting to the control, and valve. If valve opens, but red light doesn't illuminate, it could be a bad end switch on the valve. Placing a jumper across the 3 and 4 terminals should give the red light, and fire boiler. I like to look at 3, and 4 as a communication medium from the valve end switch to the control. This enables the control to know the valve opened, and it's ok to fire the boiler. If 3, and 4 never close, the boiler will not fire. It's actually shown on the instruction sheet for a two wire valve, but does not include a good explanation of why we jump 3, and 4. That's what I do; stuff like that helps me feed my children:)

    If the circumvent 3, and 4 jumper method worked, it's probably a bad end switch,, and it will be ok to leave the jumper in until you procure a 555-050RP replacement actuator. If not, you would need a replacement actuator anyway. Now you can take advantage of the manual lever to manually open the valve to allow hot water to travel to that zone when one of the other zones are calling. Obviously, you wont be able to regulate the room temperature without thermostat but you'll remain toasty until you manage to procure a replacement actuator.

    if I didn't help you with my long message, you can always call taco at 401-942-8000 and ask for the lonely Tech support department. I'm sure they will get you going.

    BTW, spraying WD40 into the valve actuator is never a good idea. thanks
    Joe Mattiello
    N. E. Regional Manger, Commercial Products
    Taco Comfort Solutions
  • Xmytruck
    Xmytruck Member Posts: 85
    edited December 2014
    Great comments I have not lube anything but it is easier to use the manual switch now. I am going to keep my eye on it, and worse case I will use the manual switch and buy a power head and swap that out if it fails. I am not a plumber but it seems like I should turn off the power, take off the wires, spin off the old head ,spin on the new head rewire and cross my fingers.

    Can I also assume that the power head is suppose to be hot to the touch?

    As always this board and members are awesome!
    Thank you
  • icesailor
    icesailor Member Posts: 7,265
    edited December 2014
    "" BTW, spraying WD40 into the valve actuator is never a good idea. thanks ""

    That applies to 4 wire valves. Not to 3 wire 57* type wax motor valves. Because I worked alone for so many years, as I got older, I found that I had to streamline my movements. Running up and down stairs is tiring for old dogs. I needed to do all my TSing at one location, at the boiler. If I put a jumper at 2 & 3, and I heard a click and a pump started, and the piston wasn't going all the way down because the lever didn't easily travel to the bottom, it was either the wax ran out, it burned out, or the coil overheated and shorted out. If it was so hard to push the manual lever down without bending it, it was going to overheat the wax motor/coil. Grease it up when you install it. I cut my zone valve teeth on White Rogers 3 and 4 way valves. A more hateful device has never been designed. I still have a 3rd degree burn scar on my wrist from one. They all ended up leaking on the O-Ring that sealed the shaft. Honeywell's did too. Not so the 57* valves. No O-Rings. I skipped the early versions of the Taco ESP valve or whatever its designation. I avoided your problems with the old tried and true 57*. I know of old 57*'s that came with green heads and have been through one or more Gold ones that I installed many years ago.

    My old long dead High School Auto Shop teacher, Mr. Wilson, used to remind us that the only function of a lubricant was to fill the microscopic space between two different pieces of metal. So Gentlemen, check your oil regularly. He also said that "You can't buy a mechanic in a can". But then said that a quart of oil was an exception.
  • Xmytruck
    Xmytruck Member Posts: 85
    edited December 2014
    Got back home and it not working I think his moring might be a fluke. :s



    Time to call a plumber. I am just shocked that it only two years old and it broken.
  • icesailor
    icesailor Member Posts: 7,265
    What kind of zone valve is this?
  • Xmytruck
    Xmytruck Member Posts: 85
    null
    Taco 571 the weird thing is the light has not turn red again but the pipes get hot after 2 hours. Can I assume that water working through the system and is getting hot because the return is getting hot. I was a electrian until I got hurt I must say heating systems gets me scratching my head.

    Thx for the help ice I appreciate it.
  • icesailor
    icesailor Member Posts: 7,265
    If you can see the ZVC, put a jumper on the #2 and #3 terminal. The red light should come on immediately.
    When the yellow light is on and the red one has not come on, can you pull the bypass lever on the side easily all the way down until it stops? If you do, does the red light come on the ZVC and does the circulator start?

    If you jump #2 and #3 and the light comes on, the head is probably bad. Look carefully on the side of the by-pass lever. It will have a date code of how old it is. If the head is warm, there is power to the valve.

    If you are comfortable, turn off the power and swap heads. If the good working head is swapped for the suspect one and it works, you have a bad head. You can also swap temporarily the #1 wires on the valve heads, and the one that is working, will work the valve that isn't working, the power head is bad.

    A couple of years ago, I had a job with two bad heads and they did what yours do. The yellow light comes on but one, the yellow light would never go out. Because the power head piston wouldn't go back up because of corrosion. I had to clean the plate and change a power head.

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