Hi folks new to this site looks like good bundle of info for a bloke like myself, anyway cut waffle, i have a r35 worcester combi and have just installed underfloor heating to all lower levels, which operated via its own control center, having re piped the system incorperating a s plan it has come to light the boiler in question will not operate with any other room stat or timer other than its own tr2 and integrated timeclock , which in turn doesn't allow me to switch the live feed ie Lr Ls terminals, when this link is split the only way the s plan will operate is leaving the integrated timer switched to operate constant thus having boiler running all the time even when there is no call for heat, worcester technical have only confirmed what i already know offering advice of no other option but new boiler. Would be extremely grateful for any advice.
worcester r35he plus s plan wiring problem
- Thread starter davewyorks
- Start date
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hi picasso, yes its wired with link out through a s plan, the only way it will work is with the integrated stat and dedicated stat tr2 calling for heat constantly, relying on the switched live through the s plan to fire the boiler, have tried it without integrated timer and tr2 stat, and it doesnt work the boiler like worcester tech say will only operate with the tr2 stat and timeclock.
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I've had this exact problem before and Worcester are right, there is not way round it. This boiler will only work with the TR2.
boiler too good to renew going to have to coincide all time clocks to work together lot of hassle i know but when it amounts to a grand will put up
if i remove tr2 picasso boiler will only work with integrated timer set to run constant. Im not impressed with worcester at all think vaillant next time.
There is a chap on this site who has done just that to enable a different roomtat to be fit, the problem is with me the stat is still volt free where as i need 240v to operate the switch wire from the s plan having split the heating zones. The way i have got it working is still having the integrated clock and tr2 operating so when they call for heat they start the boiler pump going, the boiler only then fires up when either the heating (rads) stat or underfloor heating control panel demands heat, i have incorperated a auto bypass from flow just before the two port valves across to the return taking out the pump strain whilst they are both shut, haven't a clue how long the boiler will last like this only time will tell i suppose.
Find out from the chap what resistors he used and you can subsitute them for the 10k and 1k resistors I have used in the drawing, the diagram allows you to use 240 to stop and start the boiler (if the resistors are of the correct value) View media item 47939
Hi dave
it might help if you posted a sketch of how you have wired the system, reading the above I'm persuming you have added two zone valves.
I take it that the UFH has its own controller but what is controlling the ch valve? have you also added another room stat? if so then you can fool the system using resistors and get rid of the tr2
please post exactly what you have on your system and we will see what can be done to help you
Matt
the chap in question is called oldgeeza and he says:- connect a 3.3k resistor between terminals 4 + f this makes boiler think room temp is 11 degrees, then connect a 10k + 2.2k in series between terminals 3+4 this makes boiler operate in frost protection mode, he then connected a volt free stat to either side of the 2.2k resistor thus when a demand for heat is there it shorts the resistor creating only 10k resistance making boiler think requested room temp is about 18 degrees with boiler thinking room temp is only 11 degrees the boiler fires up, clever stuff oldgeeze is a genius. All said n done i still have a problem, on the boiler in question leaves the link wire in on the ls lr terminals when the tr2 and integrated timer is used so no matter what i do with the separate terminals for the tr2 and volt free stat i still have to remove the link wire to accept a switched live sent by the two port valves. In a way by connecting resistors and fooling the boiler is what im doing now, it still will kick the pump in until the switched live fires the boiler up from the two port valves, proper head scratcher this picasso i really appreciate your time and effort your a gent the thing that gets me is why the boiler has a switched live link when worcester knew it cannot be used
Not want my help then?
I was going to do you a wiring diagram too!
But off to pub now for a few
Picasso, you are on the right lines but you seem to be forgetting that 2ports have volt free switches, no need for relays mate though I see where you are going with your diagram (by "to integrated timer" do you mean the tr2 connecting terminals?)
Dave, for now to help your head scratching
you can put back the link you have removed
you can remove the tr2
you can use any off the shelf roomstat to power the valves
you can get suitible resistors from RS etc
Matt
Hi dave
it might help if you posted a sketch of how you have wired the system, reading the above i'm persuming you have added two zone valves.
I take it that the ufh has its own controller but what is controlling the ch valve? have you also added another room stat? if so then you can fool the system using resistors and get rid of the tr2
please post exactly what you have on your system and we will see what can be done to help you
Matt[/quote] Hi matt the system is piped and wired like any normal s plan with two 2 port zone valves, one of which is controlled by a underfloor heating control centre ( uponor c56) and the radiant valve via a separate roomstat and single channel timer, i've used the live ls at the boiler to power all controls as worcester prefer and lr for return live, s plan works fine all in order, with tr2 stat removed which on this model has separate terminals, boiler only functions with integrated timer set to comfort mode i.e contant wether it set manual or timed, which makes the boiler run but not fire until other heat demand is made by another control, re adding the tr2 makes the difference of being able to control what the boiler does by the stat (tr2).
it might help if you posted a sketch of how you have wired the system, reading the above i'm persuming you have added two zone valves.
I take it that the ufh has its own controller but what is controlling the ch valve? have you also added another room stat? if so then you can fool the system using resistors and get rid of the tr2
please post exactly what you have on your system and we will see what can be done to help you
Matt[/quote] Hi matt the system is piped and wired like any normal s plan with two 2 port zone valves, one of which is controlled by a underfloor heating control centre ( uponor c56) and the radiant valve via a separate roomstat and single channel timer, i've used the live ls at the boiler to power all controls as worcester prefer and lr for return live, s plan works fine all in order, with tr2 stat removed which on this model has separate terminals, boiler only functions with integrated timer set to comfort mode i.e contant wether it set manual or timed, which makes the boiler run but not fire until other heat demand is made by another control, re adding the tr2 makes the difference of being able to control what the boiler does by the stat (tr2).
Hi dave you can still feed the roomstat and ufh controller with Ls but leave the link in place
remove the tr2, bridge out the terminals with suitable resistors as per your post above then use the valves end switches to bridge out the 2.2 resistor
I will do a diagram later if req as taxis due now
Matt
remove the tr2, bridge out the terminals with suitable resistors as per your post above then use the valves end switches to bridge out the 2.2 resistor
I will do a diagram later if req as taxis due now
Matt
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