Heating control usage problems - Horstmann Amethyst 7

[srhsloan]

Hi there,

I've just moved into a new house and the central heating and hot water are both controlled by a Horstmann Amethyst 7 timer and controller (see picture below). This is in the airing cupboard with the hot water cylinder and several valves. There is a boiler downstairs with just a single dial on it, and then a separate thermostat in the hallway.

I've got a couple of issues with it and was hoping that someone may be able to explain how it all works?

- The hot water cylinder and airing cupboard is in our bedroom and makes a constant noise - it sounds like it is pumping hot water somewhere constantly - even when the heating is off and no-one has used the hot water for several hours. It continues all night. Is this normal? The only way I've been able to get to sleep is to turn the hot water cylinder off at the mains - is this ok to do?

- The horstmann controller has a timer dial on it with 4 little knobs for indicating when the heating/water is on or off. How does this relate to the thermostat? When the heating is set to come on, will it still come on if the thermostat is turned down or does it work in conjunction with the thermostat?

- What does the little wheel in the top left of the image do? It's divided into 6 segments, 3 blue 3 red, which click round as the timer advances and moves through on/off stages for the heating and water. My understanding is that red is for on and blue for off, and that it should click to a red segment when the water is on and a blue one when it goes off. This doesn't seem to always be the case though - does this mean the unit is faulty or am I understanding it wrong?

Any help with this would be great. I've tried googling for an instruction manual but with no luck - it's so old it's not even listed on the horstmann website!

Thanks a lot.

This is the horstmann controller:

Untitled

• srhsloan
• 1 Dec 2011
• 1

 

[matt1e]

- The hot water cylinder and airing cupboard is in our bedroom and makes a constant noise - it sounds like it is pumping hot water somewhere constantly - even when the heating is off and no-one has used the hot water for several hours. It continues all night. Is this normal? The only way I've been able to get to sleep is to turn the hot water cylinder off at the mains - is this ok to do?

It may have a immersion heater fitted and it may be this you are turning off, this is an independant system to your boiler, you dont need to use both so leave it switched off as heating your water via gas will be cheaper a pic of the cylinder would be useful

- The horstmann controller has a timer dial on it with 4 little knobs for indicating when the heating/water is on or off. How does this relate to the thermostat? When the heating is set to come on, will it still come on if the thermostat is turned down or does it work in conjunction with the thermostat?

no it wont
same as it wont come on if you turn it up and the heating is set to off, it works in conjunction

- What does the little wheel in the top left of the image do?

Like it says, its an advance wheel (like a overide button)
if your heating is at an off position on the timer and you want it on early then turn it to the next red section (it saves having to reset the time settings or putting the unit on a constant on setting) it will then turn on and still turn off when the timer reaches the next off position
and vice versa if the timer is currently at an on position etc

Matt

 

[srhsloan]

Thanks a lot for this - it seems to be working as you've described and we've turned the immersion heater off all together which makes things a lot quieter!

When the heating goes off, some of the radiators stay really hot though. On saturday the heating went off at 8pm, when I got up at 8am all the radiators upstairs were still as hot as though the heating was on, but the downstairs ones were as I would expect - stone cold.

This seemed to be happening last night again but the upstairs ones went cold when I turned off the hot water switch on the timer. Is it likely that the hot water switch being 'on' (even though the timer wheel was set at being 'off') would make some of the radiators stay hot all night?

Thanks again.