# Taco zone control blowing fuses



## Hoosier Plumber

First let me confess my boiler control knowledge is not the greatest. 

Installers new Lochinvar Solution boiler In a house last week. It has 5 zone valves so a control box seemed like a good idea. 

Did a power check mid way through and only had stats, circ pump, aqua stat hooked up. Did not have any wires ran to boiler or zone valves. I'm fairly certain that is when the fuses blew. 

Today we were there to finish up and got all wiring wrapped up and discovered the blown fuses. Put replacements in and they popped. 

Verified 120 volts incoming. 27 after transformers feeding board. 

Taco says pull everything and put it back one at a time as there is back feeding. 

Not sure how that is possible as the stats are old mecury, and when the fuses originally blew the zones were not powered. 

Thoughts?


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## newyorkcity

Need pics. The "control box" you are referring to is a zone valve switching relay?


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## Hoosier Plumber

Sorry, will have to get pics next week. 

The guy at the electrical supply house looked at the fuse and said it was a .5 amp, not a 5 amp like I thought the box said. 

Looking it up now. I know the fuse is small, but .5 seems a bit low.


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## Hoosier Plumber

Taco ZVC406-4 

6 Zone with priority. 

It does look like we have .5 amp fuses not 5 amp as per the specs.


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## shlomy81

U probably have zone valve motors pulling to much amp, check resistant on the motor wire u could find the bad ones


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## Catlin987987

Do they have end switches? Might have wired up the power to the end switch instead of the power.


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## Hoosier Plumber

Update:

We finally got the problems solved and the boiler firing, or so we thought. 

Everything is wired as per the instructions and then yesterday one of the transformers blew while I was standing there looking at it.


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