Honeywell Sundial Pack 2 user settings

[farazfastian]

Based on advise from experts here i replaced my old timer with the honeywell sundial pack 2 via plumber. He installed this particular model for the first time so he couldn't advise me clearly how it works. Could someone clear following for me:

- Does thermostate always overide timer programes i.e. if temperature drops it'll always kick off the boiler irrespective of current settings on the timer?

- I want to turn off heating completely before we go to bed then turn it on at 6:30 for an hour then would like it to be controlled by theromstate at 11:00. Is it possible?

- If i turn-off the thermostate by keeping it pressed for 2 secs, will it completely not interfere timer or it'll still be doing some communicating. As i tried to do extra hour from timer but boiler wasn't kicking off until i dropped the temperature from thermostate.

- Currently i've setup hot water to run at 3 times a day and it's been running fine. Last night my wife took bath and after that there was no hot water coming in but the boiler was still off shouldn't it kick off as i've got thermostate set on the cylinder?

Please advise.

Many Thanks
Faraz

 

[45yearsagasman]

If its the rf2 pack2 that you have with the remote wireless room stat then the stat will only work if the program is set to run. Thats my understanding of how they work looking at the wiring diagram. I don't see a set back facility.

 

[farazfastian]

Yes the internal switch is set to RUN but there are two seperate buttons to control heating and hotwater with following settings:

CONT
ONCE
AUTO
OFF

Regards,
Faraz

 

[doitall]

Clearly either the programmer or room stat is wired wrong. or both.

 

[farazfastian]

room stat is wireless there shouldn't be anything wrong from it but yes timer wiring could be wrong. So are you saying that room stat shouldn't overide the timer? One thing for sure Honeywell user guide is rubbish, as it doesn't say anything about how room stat and timer works together.

 

[doitall]

No it shouldn't unless your talking frost stat which should.

A normal room stat gets it's power from the HTG call in the timer/programmer.

 

[D_Hailsham]

Yes the internal switch is set to RUN but there are two seperate buttons to control heating and hot
water with following settings:

CONT
ONCE
AUTO
OFF

CONT means the boiler is on 24/7, the only control is the room thermostat.

ONCE means the boiler is timed to come ON in the morning and go OFF at night. The thermostat should not turn the boiler on while the timer is in an OFF period.

AUTO means that there are three ON/OFF periods during the day. The boiler will only light during an ON period. The thermostat should have no effect during an OFF period.

OFF means the boiler is turned OFF and the thermostat should have no effect.

The same is true for the HW side. You change setting by pressing the button beneath the list of options.

This is all explained in the User Guide, which the installer should have given you.

 

[D_Hailsham]

A normal room stat gets it's power from the HTG call in the timer/programmer.

The Programmer part of the Sundial RF Pack 2 incorporates the Relay box of a wireless stat. This comes between the CH Switch of the programmer and the CH ON terminal.

 

[farazfastian]

Thanks for clarifying that D_Hailsham, it does say what each setting does but it doesn't say which setting you should use with thermostate which i've found in your message only. Though it further confuses me now as i've been running my timer on AUTO all the time and i've seen boiler kicking off as soon as temperature drops from the mark i set in thermostate, how that can be possible then? Is it because of wrong wiring?

 

[D_Hailsham]

Thanks for clarifying that D_Hailsham, it does say what each setting does but it doesn't say which setting you should use with thermostat which i've found in your message only.

The stat will work with any option except OFF. But I would have thought that was obvious.

Though it further confuses me now as i've been running my timer on AUTO all the time and i've seen boiler kicking off as soon as temperature drops from the mark i set in thermostat

What do you mean by "kicking off"?

 

[farazfastian]

You've mentioned stat won't effect in any option other than CONT in your definition of every option.
I meant boiler lights as soon as temperature drops.

 

[farazfastian]

I tested room stat by setting it at 20 and the timer at CONT option but for some reason boiler was lighting after every 30 mins for 5-10 mins though the temperature on room stat never dropped below 20.

 

[D_Hailsham]

You've mentioned stat won't effect in any option other than CONT in your definition of every option.

I didn't say that!

CONT means that there are no timed OFF periods over the 24 hours. So the only thing which can turn the boiler on and off is the thermostat.

ONCE means there is one timed ON period and the rest of the 24 hours is an OFF period. The thermostat will control the boiler during the ON period and have no effect during the OFF period.

AUTO means there are several ON and OFF periods over the 24 hours. Again the thermostat will only control the boiler during an ON period.

OFF means there are no timed ON periods, so the thermostat will have no effect.

During the OFF periods the required temperature is automatically set to the Frost temperature (about 5C).

I tested room stat by setting it at 20 and the timer at CONT option but for some reason boiler was lighting after every 30 mins for 5-10 mins though the temperature on room stat never dropped below 20.

That's what supposed to happen! It's keeping the room at a constant 20.

Although the drop in temperature has not registered on the thermostat (it only shows a change when it is more than 0.5 degrees), the sensor within the stat can measure much smaller changes. This is enough for the stat to turn the boiler on for a few minutes to bring the room back up to temperature.

The old mechanical stat did not turn the boiler back on until the temperature has dropped about 3 degrees. Many people would feel the drop and turn the start up to compensate. But that meant they felt too warm, so they turned the sat down again.

 

[farazfastian]

Many Thanks for the detailed reply. So basically i was doing it wrong i kept boiler on AUTO mode all the time with no periods set on it and i was assuming the thermostate will maintain the temperature BUT the thing that confuses me though even in OFF period (as there was no period set on the timer) the boiler was lighting up via thermostat to maintain temperature.

I'll try monitoring it further.

 

[D_Hailsham]

So basically i was doing it wrong i kept boiler on AUTO mode all the time with no periods set on it

The programmer comes with preset ON/OFF times. Have you changed these?