underfloor heating

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eagleeye

eagleeye

Hi guys I have just installed some underfloor heating in a new conservatory that i have just built for a customer. The father of the lady has also just fitted a new Baxi Solo boiler and has told me that the boiler only has a switched live separate pump live. The trouble with this is that if i connect the boiler, pump and UFH pump live all into the switched live on the boiler the pump is gonna run on the existing heating system. The system i have fitted is one of the JG speedfit packs with the pump and manifold all in one. I have spoken to Baxi and they have informed me that i need a Drayton RB1 relay box. I have yet to order on as yet in case its not the right thing or there is a cheaper way to do it. Any ideas or if not any ideas how i would wire the relay up. I have looked at the wiring diagram on the net but cant really figure it out

hope you can help

Regards
Paul
 
The switched live on the boiler is an input not an output. So when a valve or programmer wants to fire the boiler it must put a live onto this terminal. Normally comes from the orange wire in e motorised valve. The pump terminal is an output which allows the boiler to keep the pump running for a few minutes after the boiler has shut down to help disspate any excess heat.

I could be wrong but you need some sort of prgrammer/zone valve configuration on your flow and return pipework that will put a live onto the switched live in the boiler when there is a call for heat.
 
Hi Plucky thanks for your reply but as i said the boiler only has a switch live. so the boiler and pump live are joined in the wiring centre with the orange from the mid position valve
 
Plucky said:
The switched live on the boiler is an input not an output. So when a valve or programmer wants to fire the boiler it must put a live onto this terminal. Normally comes from the orange wire in e motorised valve. The pump terminal is an output which allows the boiler to keep the pump running for a few minutes after the boiler has shut down to help disspate any excess heat.

I could be wrong but you need some sort of prgrammer/zone valve configuration on your flow and return pipework that will put a live onto the switched live in the boiler when there is a call for heat.
Click to expand...

I think that he means that you take a seperate 3 core from the solo direct to the pump so that the pump over run can work contolled by the pcb?
 
http://www.baxi.co.uk/docs/Baxi_Solo_HE_Installation_Instructions.pdf

page 14 explains the wiring for the boiler but think the pump over run is all built in.

This works fine the way it is at the moment but its just if i connect up the switched live from the UFH control to the boiler and pump live, not only will the boiler fire up but the existing pump will run too. when all that needs to run is the UFH pump. Maybe the Drayton RB1 is the way to go
 
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If the boiler is firing then the system pump will need to be running as well.

The UFH pump is after the mixing valve so will only circulate the heating water around the UFH and not through the boiler.

Make sure you have a bypass fitted before the UFH.
 
Yes but what will also happen is that when heating only is on the UFH pump will also run even if UFH isnt calling for heat. Can pump for UFH not be wired in with the programmer for UFH?
 
think we are all getting crossed wires here. Basically the new UFH system pump has a permanent L, N, E to it and will not switch on until the room stat is calling for heat, the motorised valve is open and the heat though the pump has reached 43 degrees. When the 2 port motorised valve for the UFH opens it will send voltage to the switched live of the boiler, which is also where the existing house central heating system is connected to, therefore this will send voltage up to the pump and make it run until the UFH turns off. hope this makes it bit more clearer. What i need is something that stops voltage going to the existing pump while the UFH is on and if both are on run together. If that makes sense
 
BOTH pumps need to run together when the UFH is calling for heat. The main system pump delivers heat to the manifolds and the pump on the manifolds will ONLY pump water around the loops of the UFH circuit NOT water to and from the boiler.
 
Oh right i thought the UFH pump run the hot water roung the boiler as well. so how would this work if the boiler was only to run UFH ?? the only pump would be the UFH one
 
eagleeye said:
Oh right i thought the UFH pump run the hot water roung the boiler as well. so how would this work if the boiler was only to run UFH ?? the only pump would be the UFH one
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No, you would still need two pumps
 
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