Adding a second heating programmer

[Moneypit42]

Hello Sparkies,
I wish to have more than the 3 on/offs available with the current Drayton 241 programmer. Is anyone aware of a programmer that does this? Alternately is it feasible to connect a second programmer in parallel so they run separately to give up to 6 on/offs?
Might there be problems with one giving a reverse current live output into the dead output terminal of the other?
Ta muchly.

 

[AndyPRK]

If its got a 3 port diverter valve is maybe a problem, as the NC & NO contacts are used.

Out of interest, why more that 3? for heating ? Actually for heating only the above may not be a problem.

 

[SimonH2]

If its got a 3 port diverter valve is maybe a problem, as the NC & NO contacts are used.

That's OK as long as you wire it right.
Wire supply to common of timer 1. Wire N/C of timer 1 to common of timer 2. Wire both N/O contacts together and use for "on". Take "off" from N/C of timer 2. System will be on when either timer is on.

Out of interest, why more that 3? for heating ? Actually for heating only the above may not be a problem.

I was wondering that.

Could go back to the old fashioned mechanical time clocks. The built in one on the boiler in the flat has a load of toggles so you can set as many on and off periods you like subject to each being a minimum of 15 minutes. Basically one toggle for each 15 minute period of the day, you set each one one way for on and the other way for off.

 

[Moneypit42]

This is for heating only. Being a retired couple we want to cycle the heating in the daytime, ie 1hr on, 1hr off etc. to try to keep the bills down. There is no requirement for more than 1 hot water cycle so I’ll go with a single channel programmer. Allowing for morning & evening heating the Drayton only has 1 cycle left. As I’m a lazy devil I can’t be bothered to keep going upstairs to press the advance button so thought I’d try to automate!
No 3 port diverter here, just two separate zone valves downstream of pump, 1 hot water, 1 heating.
The boiler has no timer itself, just kicks in when the timer opens either gate valve & pump starts.
Does the given advice still hold true for a single channel?

 

[Aragorn84]

I dont really think it'll have the desired effect in terms of reducing the gas bill...

When the boiler comes on it'll run flat out for an hour bringing the system and rooms back up to temperature, then it'll shut off for an hour and everything will cool back down, repeating the cycle an hour later.

With a proper room stat set correctly you'll use no more energy, because the boiler will cycle itself on and off once the room is at the desired temperature.

All you'll end up achieving is big temperature swings?

 

[EFLImpudence]

You could use the mechanical timer (as already mentioned) in series with the programmer CH output.

I.e it could be set to on for the times you want the programmer on and then off/on throughout the day or set the programmer to permanent on.
In effect over riding the programmer.


If I am right in thinking there is no thermostat, it would probably serve the same (money saving) purpose to fit one as this would stop the boiler and pump continually running when not required.

 

[Moneypit42]

There is only one room thermostat which is in the hall. This is a cold area due to its north facing wall. This is turned right up to avoid it overiding the boiler stat thus preventing the boiler from running the other rads as we don't need this space at 70c but want higher temp in the other rooms. As all rads except the bathroom have TRVs fitted which I think went in long after the heating system was installed we use those to control individual room temps. I thought a 45 min on/off cycle would be more economical than running the boiler all day.

 

[TheVictorian]

Your money would be far far better spent on insulation and draught proofing.

 

[Moneypit42]

Cavity wall insulation is applied but I think not too good in places. Phoned a company & they won’t try to put more in. Draught proofing is in progress but I still don’t want the hall stat overriding the boiler and cooling the other rooms. Maybe I could move the stat?

 

[Aragorn84]

There is only one room thermostat which is in the hall. This is a cold area due to its north facing wall. This is turned right up to avoid it overiding the boiler stat thus preventing the boiler from running the other rads as we don't need this space at 70c but want higher temp in the other rooms. As all rads except the bathroom have TRVs fitted which I think went in long after the heating system was installed we use those to control individual room temps. I thought a 45 min on/off cycle would be more economical than running the boiler all day.

My parents had this issue.

I fitted a wireless room stat, and put it in their living room, and set the living room TRV to maximum.

Dial in the required temperature on the room stat and bingo, room stays warm. Wind back the rest of the TRV's around the house to provide the desired level of heat in those spaces.

 

[EFLImpudence]

Not too expensive -

http://www.screwfix.com/p/horstmann-hrfs1-programmable-room-thermostat/93829

 

[Moneypit42]

This sounds like the best way to go. The stat is on the hall/living room party wall so just a hole & a bit of wiring. I’ll try that first as it’s free! I’ll leave the second timer idea on the back burner & chase the draught proofing.
Thank you all for your very useful and knowledgeable inputs. If you haven’t seen the Tom Hanks film ‘Money pit’ look out for it!
Cheers.

 

[AndyPRK]

I don't know if that one does it, but you can get digital stats so you can have different temperatures during different time periods.

Therefore set a lower temperature during daylight hours to keep the bills down.


or

you could fit (on the floor you live during the day) a simple mechanical stat to bypass the timer. Simply turn this up when you want it on, and off before going to bed.
This stat would also be set to a lower level than the normal stat to keep bills down during daylight hours.

 

[EFLImpudence]

I don't know if that one does it, but you can get digital stats so you can have different temperatures during different time periods.

Yes it does.

Instructions

 

[Scoby_Beasley]

Instructions

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