Honeywell CM927

Mr_Ted

???

stevemcol wrote: »

Mr Ted. I counted 7 exclamation marks! I didn't think room stats could be that exciting.

Ahh now, thats because whilst you were sat in class making sarcastic comment about all unsundry and not concentrating on the subject matter, I was learning about the English language, you know that dying art innit!
Maybe it could just be that I was making a statement or claim? Much as a question mark can be used for something questionable?
Concentrate on the math and you may do OK?

???

wrote:

The CM927 does seem to do a pretty good job of predicting the house warm-up profile though, without knowing the OAT.

"seem to do a pretty good job" is not the Optimium then is it?

???

wrote:

All stats, works best if fixed in a communal area (hallway) and the rad in that area mustn't be rad stat controlled. It predicts the warm up rate well and maintains the home's core temperature whilst individual rooms can be regulated with rad stats.

"It predicts the warm up rate", no, it senses the actual temperature at its location and reacts to its set point!
"warm up rate well and maintains the home's core temperature", no, warm up rates are determined by the outputs of boiler and radiator sizes, and core temperatures will only be acheived if all spaces are open and all outputs are on full, that is not usually the most economical or optimum way of using heating!

???

wrote:

With wireless stats, people do make the mistake of moving them around the house, which is never going to provide effective control.

It actually provides very effective control and economy, for the space where you move it to and you may want to be specifically controlled, although that will also determine the rest of the area's accordingly!

???

wrote:

I live in an exposed 3 bed corner semi and my combined fuel bill is less than £1k p.a. When the house is occupied I always set a target 19° which will be achieved when we get home from work, without significant waste.

This is purely related to your specifics and not a generalisation as others will be extremely unlikely to have exactly the same circumstances or requirements!

P. S. "All stats, works best if " ??? so before being critical of others, may I suggest, using the Queens English, you keep yer freakin gob shut???
:T:rotfl:

Mr_Ted

macman wrote: »

Thanks for that info. So how does my CM907 optimiser calclulate the start up time, given that it does not have the external sensor fitted? It clearly functions without the sensor, as the start up time does vary quite widely.

NP!

As you describe it, yours will be in guesstimising mode calculated from fixed internal standard backup parameter programme data which is used as a fail safe(factory settings), or for circumstances as per your installation, with no OAT sensor!

Most Optimisers and Compensators have standardised parameter data inbuilt for programming and as a backup, basically to give the system something to work with, and as i said as a failsafe programme, most of these are progammable for changing to your actual requirements.
Pretty much as a PC would be useless without an operating system, this data is inbuilt as part of the operating system!

To actually work at its Optimum it does require an OAT sensor, because as i previously said, an Optimiser is basically a "Weather dependant time clock" therefore the external weather condition has to be a factored in to calculate the optimum performance for your set needs!
May well be worth spending a few quid on one to achieve even better performance?

Sad to say I have come across, in my time, many controllers that have just been installed and not set up due to a lack of knowledge of how they actually work and the setings that may be needed, and left in factory settings, which will work, but not to the optimum needs of any installation, domestic or commercial.
Needless to say I wont go into them, heating curves and the bending of heating curves and the likes, it will scare the average user of this site

jellie

Mr_Ted wrote: »

Ahh now, thats because whilst you were sat in class making sarcastic comment about all unsundry and not concentrating on the subject matter, I was learning about the English language, you know that dying art innit!
Maybe it could just be that I was making a statement orclaim? Much as a question mark can be used for something questionable?
Concentrate on the math and you may do OK?

Mr_Ted wrote: »

although that will also determine the rest of the area's accordingly!

Mr_Ted wrote: »

so before being critical of others, may I suggest, using the Queens English, you keep yer freakin gob shut???
:T:rotfl:

I wouldn't normally do this because on an internet forum it doesn't really matter, but given the vitriolic nature of your response I couldn't help it. The highlighted word is a plural and as such, doesn't require an apostrophe.

stevemcol

Mr Ted, ......My sentence originally started, 'the stat works best' then I changed it to 'all stats..', sorry if the resulting error offended you.

Your first sentence is bang on though, we must have gone to school together and I suspect I spent my time throwing things at the back of your head.

It's maths not math. You then went on to use the term 'freakin'. Are you American? If so, I will make allowances.

A few points on which we differ:

If you take a wireless stat round the house with you, it will tend to compete with the room rad stats. You may eventually get the temperature you want in that room but it will disrupt the rest of the house. The stat should ideally be mounted in the space heated by the last rad on the system which should not be rad stat controlled.

Agree 'Optimiser' is probably not the most appropriate word. In that the stat does attempt to achieve the set point at a pre-programmed time, that's as close to optimum I'd hope for in a domestic property.

The stat does indeed 'predict the warm up rate'. From Honeywell's literature: The thermostat will monitor the
accuracy of the start up and use this information to
modify the calculation for the following day by changing
the ramp rate (initial 3 K/hr)

They call the system Optimised Start.
The rest of your post...semantics really. I won't argue line by line.

I like the CM927, it works well in my house and I imagine would perform just as well in most centrally heated, well insulated properties. Other room stat / programmers are available etc etc.

Mr_Ted

jellie wrote: »

I wouldn't normally do this because on an internet forum it doesn't really matter, but given the vitriolic nature of your response I couldn't help it. The highlighted word is a plural and as such, doesn't require an apostrophe.

:T:T:T
Thats the problem isn't it!
You just can't help yourselves, can you, much as the person my VITROLIC response was directed at?
DON'T SHOOT THE MESSENGER AS YOU MAY GET SHOT AT!
So many people with double standards who expect NOT to receive a response, WRONG!!!

Mr_Ted

stevemcol wrote: »

Mr Ted, ......My sentence originally started, 'the stat works best' then I changed it to 'all stats..', sorry if the resulting error offended you.

Your first sentence is bang on though, we must have gone to school together and I suspect I spent my time throwing things at the back of your head.

It's maths not math. You then went on to use the term 'freakin'. Are you American? If so, I will make allowances.

A few points on which we differ:

If you take a wireless stat round the house with you, it will tend to compete with the room rad stats. You may eventually get the temperature you want in that room but it will disrupt the rest of the house. The stat should ideally be mounted in the space heated by the last rad on the system which should not be rad stat controlled.

Agree 'Optimiser' is probably not the most appropriate word. In that the stat does attempt to achieve the set point at a pre-programmed time, that's as close to optimum I'd hope for in a domestic property.

The stat does indeed 'predict the warm up rate'. From Honeywell's literature: The thermostat will monitor the
accuracy of the start up and use this information to
modify the calculation for the following day by changing
the ramp rate (initial 3 K/hr)

They call the system Optimised Start.
The rest of your post...semantics really. I won't argue line by line.

I like the CM927, it works well in my house and I imagine would perform just as well in most centrally heated, well insulated properties. Other room stat / programmers are available etc etc.

:rotfl::rotfl::rotfl:

You wanted to start spliting hairs, choose someone else now, and if you had thrown anything at the back of my head it would only have been ONCE

jellie

Mr_Ted wrote: »

:T:T:T
Thats the problem isn't it!
You just can't help yourselves, can you, much as the person my VITROLIC response was directed at?
DON'T SHOOT THE MESSENGER AS YOU MAY GET SHOT AT!
So many people with double standards who expect NOT to receive a response, WRONG!!!

I most certainly don't have double standards - my post was calm, polite and I provided an explanation for it. I don't believe I shot anybody, including the messenger.

I guess that's because my own education taught me the benefit of having manners.

Mr_Ted

Then keep your opinions to the point and to the post, as others should, if you DONT want a response?
If anyone wants to be sarky then expect a sarky response BACK!
Also if you dont bring any actual trade expertise, or resolution by way of experience, to the post of someone, which neither jellie nor stevemcol seem to have, but just want bragging rights, try Hyde Park Corner!

WHO ELECTED YOU AS CENSORS or DICTATORS?

My apologies to the OP for the interference of idiots who say they have manners but they must be bad, as they make irrelevent indiscriminate comment that have nothing to do with the technicalities of what is being discussed, and with no expertise of the issues at hand!
It is a sad reflection on todays society where people involve themselves with matters that are nothing to do with them, and have the arrogance to criticise others when they seem to have nothing constructive to contribute, and nothing better to do!
These are the sorts of people who cause trouble when they feel safe on the internet but probably hide behind curtains when there are real issues in the real world, and prescibe to knowing lots about things they actually know nothing about!

THE WORLD SEEMS TO BE FULL OF EDUCATED IDIOTS???