Viessmann Trouble Slow Heat Up

[999]

Why don't you disconnect the Tado and try out the weather compensation on its own before spending more money on another Tado system.

 

[Julian Such]

#Update. Viessmann advised that the Tado is doing nothing (opening valves). The heat request is generated by the WC. But as my fitters have fitted a two pipe system the HW will struggle to reach temp once it gets warmer outside. Furthermore whilst the Tado closes the valve the boiler still wants to fire. So the solution would appear to be 1, fix the four pipe solution 2, if I want to keep geofencing get a Tado V3.

 

[999]

Why wasn't the 4 pipe system utilised when it was fitted ?

 

[Julian Such]

Thats a question for my Viessmann approved fitter?

 

[999]

Using 2 pipe is no good if your using weather compensation as the hot water won't get to temperature as quite rightly pointed out by Viessmann.

 

[999]

Post a couple of pictures of your set up, boiler, cylinder, wiring etc.
Would be good to see, there may be a reason behind not using the 4 pipe but without seeing the system it's hard to say

 

[ShaunCorbs]

Agree with the above that's why the 4 piper has hot water priority

 

[Julian Such]

Agree with the above that's why the 4 piper has hot water priority

Update2#. My fitter has called and agrees re the four pipe and intends to fit a H1? Control box which will get me round this and go to four pipe? I have also had an update from a seperate engineer about Tado and KM Bus settings. Heres hoping.

 

[ShaunCorbs]

Did he fit the cylinder as well and any further back pics ?

 

[999]

So the cylinder is right next to the boiler and it wasn't piped up as a 4 pipe job.......

Oh dear

 

[townfanjon]

When he comes back get him to re- route the expansion hose .

 

[Julian Such]

I am just a consumer but you guys have been great, I take it because of the sharp turn in the hose?

 

[townfanjon]

I am just a consumer but you guys have been great, I take it because of the sharp turn in the hose?

Yep , when you have seen them split you would know why

 

[Julian Such]

Update - And more advice please...🙂.

Ok So if you recall my fitter fitted a two pipe system to my Viessmann 200w System boiler which was a no-no. This has now been refitted to a four pipe system. Two weeks on and we seem to be heading in the right direction. However I am getting some vibration, later in the day which can be heard in the room below. The engineer advised that I need two bypass valves as the system is presently responding to the standard valves closing and taking longer to switch off without these. This seems to make sense, any thoughts as to this approach?

 

[999]

You don't need any motorised valves if using the 4 pipe system with a cylinder sensor. That's the way I would set it up.