Vaillant VIH C120 Cylinder

[johnnyramone1234]

My diverter valve is not functioning. It is allowing hot water flow only to the radiators. The flow occurs even when the radiator switch on the control panel is turned off.

The Vaillant engineer who came out had very limited experience of working on this model. He said that it was not possible to buy a new diverter valve as Vaillant don't make them any more. He recommended a new cylinder. He really did not know how the system worked at all. He made no attempt to find the cause of why the valve was not working. He simply agreed with me that as the boiler was working and the radiators were on but there was no hot water that the valve was the logical place to start.

He advised against a DIY attempt to fix the grey box (model number VZ 3V 1) that controls the valve as it has springs in it that will pop out as soon as you open the box.

My questions are:

1. Does it sound right that there would be no spare part available? The system was new in 1992.

2. Does anyone have access to a second hand diverter valve or can suggest places to look?

3. Has anyone any ideas on how the valve can be unblocked manually even if the flow is always on both radiators and hot water? This will give me hot water until a better solution can be found?

Cheers

 

[johnnyramone1234]

It turns out that the so-called Vaillant engineer was wrong. They do in fact have spare parts for this cylinder. Just now got to re-negotiate another visit from an "engineer".

 

[simond]

Hey ho lets go

 

[johnnyramone1234]

This has turned out to be more problematical.

Vaillant have very kindly agreed to give me a new valve worth £178 but they say as a matter of policy they do not wish to get involved in working on their older models, so I need to find someone who can fit it.

I don't have any manual or other installation documents, so how easy do you guys think it will be to swap the valves over and connect the electrics to the thermostat panel on this model?

Cheers