Underfloor heating issue - ROTH

[Tmaughan]

Hi,

 

I’m wondering if anyone has any idea whats wrong with my UFH. I’ve had two plumbers out and two electricians and so far no one has been able to locate the fault.
 

Some background - it’s a new build and been in for one year. For the past year the UFH has worked fine. Then about 2 months ago the system stopped calling the boiler for heat (thermostats still working and calling for heat and the pump still kicked in and actuators all switched on and opened). 
 

I could switch the power off and back on and this tended to fix it. However past two works nothing I do gets it working. Plumber and electrician have said everything is setup correctly, wired correctly and mechanically sound so they are unsure on the issue. I am trying to get out developer to instruct a UFH specialist to take a look at the system, but they are dragging their feet. 
 

if anyone has any idea on potential cause I would be grateful on whats causing the boiler to not switch on even when all the manifold is functioning 
 

We have radiators upstairs and when we switch them on the boiler all works fine. 

[Temp]

Systems with multiple stats typically use a wiring centre (or a box with a different name) that performs a logical OR function to generate a Boiler Enable (BE) signal....

 

BE = StatA or StatB or StatC....

 

My guess is the Roth box is performing that function and probably timer functions as well. 

 

Did the electrician or plumber check if the BE signal (or whatever it's called on your system) go active at the boiler?

 

 

 

 

 

 

 

[JohnMo]

Is the signal for the boiler coming from the wiring centre or is the wiring centre signal making a 2 port actuator open, then the 2 port actuator sending a signal to the boiler?

 

If direct from wiring centre to boiler the potential free contracts should go from open to closed circuit. That should occur at the same time as the pump starts. If not 

 

1. On controller go to fitters menu

2. Go pot free contact

3. Check the Global Control is ticked

4. Check the delay time is something like 2 minutes.

 

 

 

I see you have a WiFi connection for the wiring centre, have you logged in to that, to see what it is reporting that should show the status of all the contacts.

 

This is mine, same thing with a different manufacturer label. Pot free contracts are off as there is no call for heat, but shows on when a call for heat.

 

Have you changed any settings?

 

 

[ProDave]

My money is two 2 port valves, one for radiators and one for UFH, and the feedback microswitch in the UFH one has failed.

 

Are there any 2 port motorised valves anywhere?

 

Of course this is basic stuff and it is a poor show that  plumbers and  electricians have failed to find the fault.  I hope you have not paid them?

[Tmaughan]

37 minutes ago, Temp said:

Systems with multiple stats typically use a wiring centre (or a box with a different name) that performs a logical OR function to generate a Boiler Enable (BE) signal....

 

BE = StatA or StatB or StatC....

 

My guess is the Roth box is performing that function and probably timer functions as well. 

 

Did the electrician or plumber check if the BE signal (or whatever it's called on your system) go active at the boiler?

 

 

 

 

 

 

 

Thanks for replying. I’m not sure but I’ve noted down what you’ve said so I can check with the electrician 

[Tmaughan]

37 minutes ago, JohnMo said:

Is the signal for the boiler coming from the wiring centre or is the wiring centre signal making a 2 port actuator open, then the 2 port actuator sending a signal to the boiler?

 

If direct from wiring centre to boiler the potential free contracts should go from open to closed circuit. That should occur at the same time as the pump starts. If not 

 

1. On controller go to fitters menu

2. Go pot free contact

3. Check the Global Control is ticked

4. Check the delay time is something like 2 minutes.

 

 

 

I see you have a WiFi connection for the wiring centre, have you logged in to that, to see what it is reporting that should show the status of all the contacts.

 

This is mine, same thing with a different manufacturer label. Pot free contracts are off as there is no call for heat, but shows on when a call for heat.

 

Have you changed any settings?

 

 

I’m not sure. I do know, from speaking with ROTH, that the Roth box signals to the boiler to switch on. How it does it I am unsure! 
 

on my app when the temp is set higher the pump and contact free say they are ‘ON’ and then when the temp goes down it says ‘OFF’ so those two items seem to be working as and when the temp drops etc 

 

i’ve checked and both have a 2 minute delay. 
 

ROTH logged into my app remotely and said all settings are correct

[Tmaughan]

34 minutes ago, ProDave said:

My money is two 2 port valves, one for radiators and one for UFH, and the feedback microswitch in the UFH one has failed.

 

Are there any 2 port motorised valves anywhere?

 

Of course this is basic stuff and it is a poor show that  plumbers and  electricians have failed to find the fault.  I hope you have not paid them?

I am not sure, but will ask the next electrician to make sure this has been checked. Thank you 

[JohnMo]

No sure if you have the manual but I've attached it.

 

If you have a multi meter check for a change in continuity on the potential free contracts when it's calling or not calling for heat.

User_Manual_Roth_Touchline_SL_Controller_8ch__Master__L12__20240402_UK.pdf

[Temp]

2 hours ago, JohnMo said:

No sure if you have the manual but I've attached it.

 

If you have a multi meter check for a change in continuity on the potential free contracts when it's calling or not calling for heat.

User_Manual_Roth_Touchline_SL_Controller_8ch__Master__L12__20240402_UK.pdf 7.18 MB · 1 download

 

+1

 

They are on the bottom right as shown in the diagram on page 7

 

The NO and COM pins are connected  together when its calling for heat. Not connected when it isn't.