ST699 question

[Ackoman]

Hello

My central heating and DHW system uses a Honeywell ST699 timer - it seems to me that not being able to independently time the central heating and the hot water is a disadvantage, however the ST699 seems so popular that I can only assume that most people have no issue with not being able to independently time them.

I'd be interested in hearing other people's thoughts on this subject!

Thanks,

Ackoman

 

[DP]

Programmer no longer have square wheels like 699 had. Good timer in its day but we have moved into 21st century, honestly

It is not uncommon to have three switching periods, automatic time adjustment, independent channels, to name a few

 

[Iamchamps]

Not sure where your st699 is located mine is in the kitchen. I have my hot water and heating come on at the same time then after half hour / hour I just click the water to off and leave heating on to me that's the norm and never felt inconvient.

I have just had a new boiler fitted and will be upgrading to a st9400c when the electrician has sorted the wiring to allow me 7 day programming instead of 1 day.

 

[JohnD]

Assuming you already have a (most likely wired) wall thermostat, you can change it to a programmable stat with relative ease, and control your CH independently.

Most likely you have a thermostat on your cylinder, which will turn off the HW when the cylinder is hot.

 

[Ackoman]

Assuming you already have a (most likely wired) wall thermostat, you can change it to a programmable stat with relative ease, and control your CH independently.

Most likely you have a thermostat on your cylinder, which will turn off the HW when the cylinder is hot.

Ahhhh, OK - let the thermostat do the timing and turn the ST699 to continuous?

 

[JohnD]

yes, for CH

 

[Ackoman]

yes, for CH

Presumably, any programmable thermostat that then replaces the wired thermostat then just needs to be wired up as if it were a standard 230V switching thermo connected to a combi boiler, and I don't need to follow the instructions for connection to a Y plan because that is all still taken care of by the ST699?

e.g. If I was to get a Salus it500 then I would follow diagram B on page 4 of this:

http://www.salus-tech.com/cache/fil...ibrary/2016/5/iT500-Installer-Manual-UK-1.pdf

 

[JohnD]

can't you afford anything better than a Salus?

 

[Ackoman]

can't you afford anything better than a Salus?

Possibly - what do you recommend?

 

[JohnD]

I am a householder not a plumber, but I haven't seen anything better than Honeywell. I replaced my old wall stat with a CM907 (currently £67 at Plumbworld) and it was an easy swap, does everything I want.

 

[Ackoman]

I am a householder not a plumber, but I haven't seen anything better than Honeywell. I replaced my old wall stat with a CM907 (currently £67 at Plumbworld) and it was an easy swap, does everything I want.

Ah OK - I quite fancy having a Wifi controlled one though....

 

[JohnD]

more to go wrong....

Salus is an infra-budget brand