Hot water timer unit replacement

[casper165]

We have just moved into a house with a broken mechanical timer unit for the hot water only. The current one fitted is this unit:

2707871F-DBE5-4581-9C7A-BBD2A3D4209E

• casper165
• 6 Jan 2022

D97D98EA-7A3B-4757-9888-09D12BDD924F

• casper165
• 6 Jan 2022

Am I right that wires 1&2 are the power feed, but which of 3&4 is the switched live and which is the neutral?

The whole system is complex and I only want to replace this timer to keep us going as the whole system needs upgrading to give more control in the future.

 

[flameport]

1&2 are the supply L&N for the timer.
3&4 are live and switched live. Which is which isn't possible to know from the image, but it doesn't matter - all it's doing is connecting 3&4 together when hot water is required.
5 isn't used.

As the wires unusually have markers on them, is there a manual or other documentation for the system?

 

[casper165]

This is the control panel for the heating and water, not exactly standard for a domestic property!, hence I only want to change the timer at the minute.

586DD52E-5732-4479-BDD0-E5BAF9346D9B

• casper165
• 6 Jan 2022

Control Panel

BFA3ABD9-B479-4761-BF6E-E437889B11FE

• casper165
• 6 Jan 2022

Control Panel rear of door

19C222DA-8D89-41F0-B1FD-5CAC1C025F07

• casper165
• 6 Jan 2022

Control Panel wiring

 

[flameport]

This is a replacement: https://www.tlc-direct.co.uk/Products/SMNTT02.html although that's only a 24h. 7 day mechanical types are fairly unusual now.
or this electronic version: https://www.tlc-direct.co.uk/Products/SMNTT04.html

 

[casper165]

Flameport,

Many thanks for taking the time to look at this and recommend a replacement. I’ll order the digital one, thank you.

 

[oceansoul]

Well that's not your standard domestic heating control!

 

[SUNRAY]

The mere fact the wires in 1&3 have markers '1' indicates to me that 3 is the live, however it's only a switch contact so it matters not which way round 3&4 are connected.
It seems strange they haven't used the connector plate that usually comes with it and then they wouldn't have needed to add the 'spare' red crimp to insulate it.

 

[333rocky333]

Before you buy the Timer have you checked the Hot water actually works.
This can be done using the switch on the face of the timeclock, marked O and I
If you desired you could use the switch to control for the time being rather than getting a clock

 

[mcprinter]

That is impressive.
Did the previous owner work at Chernobyl?

 

[ericmark]

Seems it is a under floor heating unit using an electric boiler and is rather complex, but seems not all the units are 230 volt I see 24 volt AC and 0 - 10 volt so would be wary with 1 and 54 to 4 and 3 may not be 230 volt.

Hunted and found this on the main controller glad not down to me to sort out.

 

[Harry Bloomfield]

Hunted and found this on the main controller glad not down to me to sort out.

The inside of the panel, looks as if someone has already done battle with it

 

[casper165]

Before you buy the Timer have you checked the Hot water actually works.
This can be done using the switch on the face of the timeclock, marked O and I
If you desired you could use the switch to control for the time being rather than getting a clock

Works fine in the 0&1 positions but I just want more control when it is on and off, due to the complexity of the system we are struggling to get a heating engineer to do the upgrades at the minute so until we do the timer will do.

 

[casper165]

The heating system comes from an oil boiler, we have Wirsbo ( now Uponor) UFH heating with actuator control units and thermostats on the lower voltage side, hence not all is 230V, the bolier and hot water (boiler and immersion) are on the 230v side.

 

[casper165]

That is impressive.
Did the previous owner work at Chernobyl?

The original owner built hotels and gyms hence the commercial feel to the heating, the electrics, especially the lights are built on similar style systems!, going to take a while to get my head around it all and modernise it to a more domestic looking system.

 

[SUNRAY]

The inside of the panel, looks as if someone has already done battle with it

Well for a start I'll make the statement the original is a classic example of a controls/wireman nicely built panel but the electricians on site made a typical horrible f****p of a ****take job. They ignored the earth bar provided for the field wiring but diverted the controller's earth wire to provide those 4 earth terminals in the middle, if they had to do it - why not put them on the terminal rail with the other terminals?
There is also evidence of significant modifications as demonstrated by the lack of wire numbers on the controller. I'm not an expert on that particular controller but it looks to be classically wired for UFH work