Boiler/Thermostat Worcester RD537i

[Rwmc6]

I have a Worcester RD537i which is about 16 years old. We only moved into the house in October and made the decision to keep the boiler until it goes.

The boiler has a Worcester TR2 thermostat which we use to set the temperature. I believe that this boiler can only be operated with this thermostat and can’t be replaced with a Hive etc. due to the setup (which I’ve kind of made peace with now)

Anyway, my issue is the last week or so we have noticed that the heating isn’t coming on when we have turned up the TR2 thermostat to say 25 degrees. I’ve checked the “required temperature” on the boiler which is what the boiler thinks the thermostat is set at and it has generally been 2.5 degrees lower than the thermostat.

Again, this morning the boiler didn’t fire despite the thermostat being set at 25 degrees so I checked the boiler and it showed a required temperature of 14 degrees. When I turned the thermostat up to 30 degrees the boiler came on and showed a required temperature of 29.5 degrees.

Is my thermostat knackered and will getting a replacement (if I can source it) rectify the problem?

 

[denso13]

Not sure if this helps https://www.diynot.com/diy/threads/tr2-reading-wrong-temperature-any-fixes.499407/

 

[Rwmc6]

Not sure if this helps https://www.diynot.com/diy/threads/tr2-reading-wrong-temperature-any-fixes.499407/

Thanks, yes I did read that thread before posting.

It’s a similar issue although my boiler is definitely set on comfort mode so it should be the TR2 which specifies the temperature. However the TR2 seems to be telling the boiler the wrong temperature and is erratic. Sometimes there is a 0.5 degree discrepancy between the TR2 and boiler, and sometimes it can be 11 degrees discrepancy.

I believe the TR2 is also 16 years old so not sure if it’s just came to the end of its life?

 

[Deleted member 267285]

Who said it can’t have a Hive? Just read the manual which states it can have an external room thermostat. What you may need is a gas safe registered engineer to complete the work as it involves removing the cover which can form part of the combustion circuit.

 

[Rwmc6]

Who said it can’t have a Hive? Just read the manual which states it can have an external room thermostat. What you may need is a gas safe registered engineer to complete the work as it involves removing the cover which can form part of the combustion circuit.

All the threads on here suggest this boiler isn’t compatible with Hive or any other thermostat. I believe some have found a work around which leaves the pump running at all times (which I don’t think is a good idea)... so I believe my options are TR2 or TR2 unless someone knows different to what I’ve been able to find online?

i should add that Hive list this boiler as one of very few which aren’t compatible with their system.

 

[Deleted member 267285]

I haven’t read any of the threads on here, just the installation manual, I couldn’t find any reason not to fit a 3rd party controller.

 

[denso13]

Who said it can’t have a Hive?

Chris, there are a number of Worcesters that can only use the TR2 and I think the boiler above is one of them.

 

[denso13]

Bottom of this page https://community.hivehome.com/s/article/Is-Hive-Active-Heating-compatible-with-all-types-of-boiler

 

[Rwmc6]

Do you think it is my thermostat which sounds like the issue? Is my only option to try source and old TR2 thermostat?

 

[Deleted member 267285]

Bottom of this page https://community.hivehome.com/s/article/Is-Hive-Active-Heating-compatible-with-all-types-of-boiler

Not sure why it wouldn’t work? However the model number is slightly different from that of OP, rebadged for British Gas, but looking in the instructions seems like it would work. Leave it up to OP then.

Attached photo of what’s in the British Gas 537i and no mention of this TR2. Again not sure why it wouldn’t but that’s my opinion.

 

[denso13]

Do you think it is my thermostat which sounds like the issue?

Hard to say really but possible. I wouldn't like to advise that you buy another one only to find there is no difference.

 

[Rwmc6]

Not sure why it wouldn’t work? However the model number is slightly different from that of OP, rebadged for British Gas, but looking in the instructions seems like it would work. Leave it up to OP then.

Attached photo of what’s in the British Gas 537i and no mention of this TR2. Again not sure why it wouldn’t but that’s my opinion.

It’s the British Gas badged version I have. It’s GC number is 4710811 according to the original manual I have here.

The manual seems slightly different to what you attached as says that “externally wired controls are not required. The boiler has built in text display programmer and frost protection. The TR2 room thermostat provides additional frost protection...”
https://ibb.co/0t8m3Vs

 

[stem]

Hmmm. This sounds familiar, I seem to remember falling foul of something like this a few years back. I can't remember the model number, but I recall a WB boiler equipped with the usual Ls Lr and Ns terminals that are associated with remote controls but when wired up they didn't work.

The manual I found for a RD537i suggests this might be the case with this model. This is the only information relating to external wiring connections.

Having said that the circuit board diagram does show a link between Ls & Lr which you would expect on a model that does allow external controls....

 

[ianmcd]

I believe that this boiler can only be operated with this thermostat and can’t be replaced with a Hive etc. due to the setup (which I’ve kind of made peace with now)

you can use any timer or thermostat you want including Hive, they simply wire into ST8, switching is 240v

 

[Rwmc6]

you can use any timer or thermostat you want including Hive, they simply wire into ST8, switching is 240v

Despite the post above? Have you done this before mate on one of these boilers?