Danfoss tp5000si thermostat display problems

[ross sears]

My Danfoss tp5000si display has all of a sudden stopped displaying the time and intstead shows only 2 dots flashing where the time normally is and also the temperature, which when i first looked was down at 5c. I moved to temp upto normal 20c and it switched on and the heating came on as normal. But it seems to be switching on and off very quicklky. I have tried all the resets from the manual and nothing happens. Tried the batteries also nothing happened. I have 2 of these thermostats in our 3 story house and the upstairs 1 is working normal, although i did recently change the lower temperature up a little bit. Will this have an affect? Any ideas?

 

[DP]

Press the up and down button together once and see if issue resolves

 

[ross sears]

Tried that. Nothing

 

[ross sears]

Going to shut the whole system down for 10 minutes see if the issue resolves

 

[Deleted member 267285]

Did you use good quality alkaline batteries?

 

[ross sears]

I put rechargeable ones in. Bad idea? Going to look for good batteries, although the low battery symbol never appeared.

 

[Deleted member 267285]

I’m not sure with that, but always told to use good quality alkaline ones. I have customers who try to change them for the cheap zinc batteries.

 

[Harry Bloomfield]

I put rechargeable ones in. Bad idea? Going to look for good batteries, although the low battery symbol never appeared.

Yep, bad idea. Rechargeables have a lower voltage than decent alkalines, so will cause a low battery warning.

 

[ross sears]

Did you use good quality alkaline batteries?

Changed for good alkaline batteries, still the same issue.

 

[ross sears]

Yep, bad idea. Rechargeables have a lower voltage than decent alkalines, so will cause a low battery warning.

Ok thanks for the info, didn’t know that. I changed for normal alkaline and still jo result

 

[Harry Bloomfield]

Ok thanks for the info, didn’t know that. I changed for normal alkaline and still jo result

Might the instruction suggest the flashing indicates it has lost pairing with the receiver - maybe needs repairing if a wireless unit?

 

[ross sears]

Might the instruction suggest the flashing indicates it has lost pairing with the receiver - maybe needs repairing if a wireless unit?

Its a wired unit

 

[Harry Bloomfield]

Its a wired unit

OK, strange that it should need batteries - what does the manual suggest the flashing might be?

 

[ross sears]

OK, strange that it should need batteries - what does the manual suggest the flashing might be?

It doesn’t say anything about it, I can’t find any troubleshooting information anywhere! I think it’s wired not the system but not powered by it, because when i turn the mains off to the heating system the thermo is still on.

 

[Deleted member 267285]

OK, strange that it should need batteries -

On the contrary, quite a lot of hard wired thermostats use batteries, especially ones that do not require a neutral wire.