Identifying parts

[Roberto2019]

I have just dismantled my old oil boiler (22 yrs old) and electrics that go along with it. A new one will be installed later in the year, and moved to a different location due to building works.

In doing so, there are a couple of components in the electrics that I have no idea what they are for.

The system is gravity hot water, plus pump for central heating.

There is one room thermostat, and a thermostat on the hot water tank, which is connected to a single motorised valve to control the hot water.

The timer is a Randall/Danfoss 103. All very simple.

There are two other components that I have no idea what they do:

1. Next to the timer there is what looks like a room thermostat, but it has the face plate blanked off so you cant change it. Inside, you can see it does a have wheel you can turn with different temperatures written on it.

2. There is a box (very old), with a solenoid in it.

I had assumed that both of these were disconnected and were just relics from an old iteration of the system - but they are in fact all connected in..... any idea what they are for?

Many thanks

 

[Andydevon]

Frost stat?

 

[Roberto2019]

Just done some googling.... I think that could well be what No.1 is, albeit a very old one. Thank you.

As for No.2 - I wrote solenoid, but actually I think actually it could be some kind of relay switch? It has a clear case and you can see copper coils in it.... any ideas?

 

[Ihavenojob]

Just done some googling.... I think that could well be what No.1 is, albeit a very old one. Thank you.

As for No.2 - I wrote solenoid, but actually I think actually it could be some kind of relay switch? It has a clear case and you can see copper coils in it.... any ideas?

The grey box with the relay in it is more than likely an old Sunvic/Satchwell wiring centre.

 

[Roberto2019]

The relay in the box has "Schrack MT206203".... is that a wiring centre?

What is it actually doing if so?

 

[Ihavenojob]

The relay in the box has "Schrack MT206203".... is that a wiring centre?

What is it actually doing if so?

Older clocks and motorized valves needed relays to perform switching, modern programmers and valves incorporate the switches. The grey box is for connecting all the wires from the system components.

 

[martygturner]

Normally relays are used to switch a bigger load , in a car, the relay takes a say a 1 amp circuit from a switch and then when activated the internal switch inside the relay closes and the rear 10amp demister circuit is switched on. Its a way of using a small current to switch a bigger one, saves wiring the car up with thick wire....

 

[charlie275]

The relay in the box has "Schrack MT206203".... is that a wiring centre?

Perhaps you meant Schrack MT206230.

That appears to be a 230VAC 10A 2-pole C/O relay.

What's it doing?.. at a guess either load switching, or control logic. You'd have to trace the wires to figure it out.