Thermostat - batteries have leaked

[alicegoody]

I'm an absolute amateur and so I'm really sorry if this should all be obvious.

I have a wireless thermostat and the batteries have rusted inside it. It looks like it has therefore completely messed up the circuitboard and so the unit won't turn on. This means that my central heating does not go around my house as it doesn't detect anything.

My question is, can I buy any thermostat to replace it? I don't want to replace all of the wired stuff if I can help it, and I'm hoping that the new unit would just talk to the things that are already connected. Or do I need a particular model? Or can I just replace the circuitboard (I don't know where to look for these!)

 

[Mike13]

If you can take the board out you can first wash it under the tap to get the salts out of the board, then use some rubbing alcohol (Isopropyl alcohol) to get the worst of the water off it. use a small stiff brush to clean the contacts where the battery goes.
Then use a hair dryer to dray it out.
Replace and it may work. If not it might need tracks to be replaced, but that means access to a decent soldering iron etc.
But a board clean is pretty simple and can be attempted by anyone.

 

[Deleted member 267285]

You may get a Drayton Digistat 601 to link up to it, but it also may not, but you could speak to Drayton technical. Failing that I think imo replace it, rather than mess about with all that above. The heating can be overridden on the receiver to get you some heat, but won’t be thermostatically controlled.

 

[HSingh]

Hi, it might be a long shot but this maybe worth checking out/ maybe message the seller to check the specifications as it may be the Drayton equivalent and it shows it links to the old WR1 you have. There is about one day left on the listing

British Gas WR1 Receiver and Drayton Thermostat | eBay

Find many great new & used options and get the best deals for British Gas WR1 Receiver and Drayton Thermostat at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

As previously suggested contact Drayton for advice & ensure it is replaced by someone competent to do so.

 

[Rodders53]

Drayton made and re-badged those for British Gas.

The slide-in battery compartment terminals are probably fatally damaged. But some emery paper on both sides (PCB and battery slide) to remove the oxidation/rust might allow at least a temporary battery contact to be re-made?

It might be possible for the old receiver unit to learn / pair with the newer RF601 thermostat control, but if not the receiver is a simple plug/socket fix to the wallplate fixed wiring swap. So mains switch off to boiler system, loosen the two screws on the bottom of receiver, pull bottom forward and it 'hinges' off the top. New replacement is a reversal.
Then turn back on the mains to boiler and controls.

https://www.ebay.co.uk/itm/40472279...&customid=17045421850900112974716001114008005 has a picture of the (black) wallplate etc.,.

There are probably better/more versatile replacement thermostats, but they may be more difficult to swap out.

 

[RandomGrinch]

But a board clean is pretty simple and can be attempted by anyone.

I'm not one to discourage DIY board repairs, but I'm afraid that PCB is too far gone.
The copper layer has been lifted from the fibreglass substrate.
It is mostly the ground plane that is affected in that area, but you then start to lose the ground vias, that will all need to be soldered back in.
There are a couple of other tracks in the area that will likely lift straight off.
There is also evidence of corrosion on the vias further up the board.

As has been said above, new thermostat time - override at the receiver for heat in the meantime.

...and wow, I don't think I've ever seen corrosion that bad!

Edit...
Sorry, I'm wrong, it looks like it has only lifted the silkscreen/solder mask, I wasn't looking closely enough, but it has badly oxidised and corroded the copper layer beneath.
I still think, too far gone though.

 

[Mike13]

solder mask has wrinkled, but vias we can see look intact. It is an almost free way to see if the board can be revived for a bit, gives some more time to buy a replacement. It is at the very least sodden with concentrated salts from the battery, with those out of the way it might even work.

 

[RandomGrinch]

, but vias we can see look intact.

It's the upper ones that may be interesting...