Radiators always warm

[jaylockwood1978]

Hi, I have a tenant at a property and she's reported that she thought the wireless thermostat wasn't communicating with the boiler as the radiators seemed to be on all of the time, despite the program saying they shouldn't be.
my boiler is a Worcester Bosch Greenstar 28i junior and the thermostat a Salus RT500rf (I've heard they're rubbish but it's never given a problem in the last 5 years).

I popped round to check check and did all of the non-expert things I could....new batteries, checked programs, reset transmitter unit, turned receiving wall unit on and off. When I increase temp manually on wireless thermostat, the green light on receiving wall unit comes on, pilot light on boiler fires up. When I turn the temp down, the pilot light goes out, presumably turning heating off? All good I think. I then set all 5 programs to the minimum 5degrees to hopefully get the radiators to go off. Several hours later my tenant said the radiators were still hot.

i got a heating engineer out yesterday and he said the thermostat seemed fine and was doing what it was meant to do.

Tenant contacted me again today and she still thinks the thermostat isn't engaging with the boiler as the rads are still always hot.

could it be something else causing it and nothing to do with the thermostat?

Thanks in in advance for any help

 

[PrenticeBoyofDerry]

Is the diverter valve on boiler functioning correctly?

 

[jaylockwood1978]

Hi thanks for replying. I mentioned that to him earlier after I'd googled stuff and he said he doesn't think it's that as the hot water is working fine and that if water was being diverted then you'd expect the hot water from the taps to be affected? Not sure how true that is?
He is going to price up a new thermostat as he thinks that maybe it is sneaking a signal through somehow even though the programmer says it shouldn't be heating up.
Not having a clue myself I'm unsure

 

[hazetimesfive]

try changing the frequency, maybe neighbours have one too.

 

[jaylockwood1978]

The receiving unit is attached to the wall next to the boiler. Would the frequency be changed inside there if I unscrew it and take it out? Bit dubious about messing with electrics

 

[PrenticeBoyofDerry]

Hi thanks for replying. I mentioned that to him earlier after I'd googled stuff and he said he doesn't think it's that as the hot water is working fine and that if water was being diverted then you'd expect the hot water from the taps to be affected? Not sure how true that is?

If the valve has jammed in the mid-position you could have both on!

 

[hazetimesfive]

The receiving unit is attached to the wall next to the boiler. Would the frequency be changed inside there if I unscrew it and take it out? Bit dubious about messing with electrics

I don't recall, read the instructions it will tell you how to adjust it, from memory it's perfectly safe and won't require you to access anything with exposed current.

 

[bernardgreen]

try changing the frequency, maybe neighbours have one too.

The radio frequency cannot be changed but the identity code of the units can be changed.

Changing the identity code to one that is different from the next door neighbour's unit has will prevent commands from that unit affecting your unit.

But it will NOT prevent your neighbour's unit disrupting wireless communication in your system by blocking ( jamming ) the channel.

I do not know if the following applies to Salus equipment though I think it is likely to.

The basic requirement is :-
When heating is required the thermostat sends a "ON" message to the receiver, the receiver turns the boiler on. The receiver then keeps the boiler on until it receives an "OFF" message.

If that "OFF" message is not received then the boiler is not turned off. One reason the receiver does not get the "OFF" message is the channel being locked when the thermostat sends the "OFF" message,

A more sensible operation is that when heating is required the thermostat sends "ON" messages which is repeated every few minutes. Whenever it receives an "ON" message the receiver turns the boiler on but only for a preset number of minutes. After that time period the boiler is turned off. Receiving an "ON" message will restart that period.

Sending repeated "ON" message and timing out in the receiver ensures that the boiler will not be left switched on if, when heating is no longer required, the channel is blocked when the thermostat sends the "OFF" message. This fail safe operation comes withj the cost of reduced battery life due to the repeated transmission of "ON" messages

 

[shambolic]

Nice copy and paste ^^^^^^

 

[bernardgreen]

Nice copy and paste ^^^^^^

No it was not copied and pasted.

 

[it's not that hard]

It's probably the 3 way valve stuck in the mid position or if it's only the upstairs rads getting hot and downstairs they stay cold, then it hasn't been piped up properly and you are getting back circulation.

 

[picasso]

Ask the tenant if the eco button in illuminated on the front of the boiler, if the button is not lite then the hot water pre heat is on and if the diverter valve is passing the boiler will heat the rads.

 

[ServiceNumpty]

Could also be the setback temperature is set too high, so in effect not switching the boiler off. The SALUS has 2 on/setback periods plus a fifth setback overnight setting.