Electric unvented cylinder - operation & controls?

Joined
27 Oct 2003
Messages
312
Reaction score
5
Country
United Kingdom
My friend aked me to try to figure out the CH & DHW controls in his new flat, but unfortunately I'm unfamiliar with the system he has installed so was looking for some insights. Apologies but I didn't get any photos so will try to explain what I saw and hopefully this will trigger an "ah yes that's a totally standard X installation" response!

The property is electric only (no gas). There's a 300ltr direct unvented cylinder, and CH is via typical wet CH system of radiators. The cylinder has 2 heating elements. The upper one is controlled by a Horstman economy 7 controller (both standard and boost cables are wired to the same element). The lower one had a wire heading off into a FCU on the wall. Above the horstman control there was a drayton controller with no visible wires, so I'm guessing this controls the lower element via wires buried in the wall to the FCU.

I have a few questions:
- Is it typical to have 2 seperate controllers, independently connected to the two heating elements? If so is one for CH and the other for DHW?
- What does the inside of the tank look like? Are there 2 compartments, one containing water for the CH and the other DHW?

EDIT: I just discovered that a strange white box I saw was an electric boiler, so clearly this is inline with the CH and must be time-controlled by the drayton programmer. My only query then is what's going on with the 2 separate time-controllers? I'm not sure if the boiler is providing indirect DHW heating, so the immersion heaters are backup only, or if the immersion heaters are the primary source, in which case I have no idea what controls the bottom element...
 
Sponsored Links
Hopefully the bottom element is also wired to the Hortsman timer, through some cable concealed in the wall.

The electric boiler for the radiators is probably a completely separate installation, although one can never be sure.

Photos would help.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top