Viessmann Control Question

Jay_insula1203

I went to service a Viessmann Vitola 200 with Viotronic Control that was having DHW problems in half the house. I found the system had two indirects. One was a Vitocell 300-V 119 gallon and the other a 52 Gallon Boch. The Boch was at the far end of this very long large house. There is a taco zone control for the five Taco zones valves and one is for the Bock Indirect.
Naturally with the warm weather the heating zones are in WWSD which includes the small indirect. Two things puzzle me 1. Why they are just noticing now (system has been in for 10 years and not installed by my company)
2. And if it was working how was it working?
Can the WWSD be turned off by programing, or could I use 12X to run the burner ? I already know how to make the Cir. run on a call from the Bock.
Thanks for any input

Jay

HVACNUT

@Jay_insula1203. I don't know if this will help you, but for what its worth...

Big Ed_4

Ten years is an long time for noticing the problem .. So the Bock zone valve control is powered off durning warm weather ? And now they noticed the problem ? Yes you have to scratch your head..

One reason it may not have been notice , if its an older owner in an larger house , When your young,making money and raising an family , you want that bigger home with lots of rooms .. When you get older , what do you need , three maybe four rooms ... Maybe no one wanted to use the far bath on the West wing ? ... Until someone was invited to visit ...


Another thought ... The second Bock was added later , and if both are connected to the same hot and cold water lines , an gravity flow will want to form.The heated storage of hot water will heat the other tank. ,if the restriction is not greater then the force of gravity ..

Jay_insula1203

Oops Getting my jobs mixed up, the system is a Vitola 200 with Viotronic control.
My quick and very Temp. fix was to interrupt the outdoor sensor with the Normally closed contact on the Taco zone controller. When the boiler does not know the outdoor temp. The burner fires and the circulator is activated and the 2nd indirect works. The customer informed me the Hot water is much quicker. So Big Ed may be correct the far wing was always getting Hot water from the main indirect, and the 2nd indirect was only working in the winter. The funny thing is the house is summer only and is drained and winterized for winter. Same question will X12 fired the burner when control is in WWSD?
Thanks
Jay

Paul Pollets

Viessmann recommends that indirect tanks be located within 20 feet of the boiler and near-boiler piping. I would start there.

GW

It's been some years since I've been familiar with that control. Most Viessmann controls (not all) have an ability to run the boiler to high limit. That is probably what's going on here