I'm hoping someone can help me work out my central heating system please... I've just moved into a new house with an unvented OSO cylinder, a Danfoss FP720 programmer and underfloor heating controlled by Aube TH 232 thermostats and it is starting to drive me crazy!!
We have 3 bathrooms with showers, 1 of which is on the 1st floor, and the kitchen located in between - The boiler, OSO Cylinder and Danfoss Programmer are all located in the garage. What looks to me as the logical and most direct layout as per sitings or rooms is as follows:
1. Garage and cylinder
2. Bathroom 1 (ground floor)
3. Kitchen
4. Bathroom 2 (main house bathroom, ground floor)
5. Bathroom 3 (upstairs)
I have a few questions about this set up and really hope someone can help me please.
We moved in 3 weeks ago and the Hot water has mostly been ok, there are 4 of us living here (wife and 2 daughters) none of whom ever has less than a 10 minute shower. The water has always taken longer to reach bathrooms 2 & 3 and I presumed this is purely down to the distance it needs to travel through the pipes, possibly 30-40 meters.
Problem 1
The last day and a half we have not had any hot water. The timer and programmer shows the light saying that it is on for both heating and DHW but I can run the tap for ages in all rooms and still don't get any Hot water.
It could be that I am misunderstanding how to use the cylinder and controls properly as I have always had a combi system previously. Attached are photos showing the cylinder and controls on the wall and I believe the programmer is set up correctly and how we want it.
One thing to note - The switch that is labelled "water heater" has not always been on. I have just turned this on today as I thought it controlled one of the immersion elements and therefore essentially kept the heater on continuously - which goes against the point of having a timer and programmer... Is that correct? I started to think that the switch was the over riding power control for the cylinder but then we wouldn't have had hot water for 2 weeks if it was switched off would we??
The older style timer clock above the programmer is for a pool pump and filter system so shouldn't affect it at all.
There are 2 white cables coming from the cylinder that I can see and think they go to the wiring centre above the heater switch (for main power?) and into (or from) the water heater fused switch. The wiring centre is obviously wired to the programmer and the other white cable seen coming from it I believe goes to a motorised valve after the black circle thingy.
I am on an Economy 20 Plus electricity tariff and have the DHW set to come on at 05:00 for 3hrs, 15:00 for 2hrs and 19:00 for 2hrs to try to cope with our hot water needs.
How does the system work? As far as I understood it, there are 2 heating elements inside the cylinder - top and bottom - with the bottom one heating the majority of the water on the set programme. The top element then boosts the heat of the water when boost is used or automatically when the thermostats sense that it is not hot enough.
I don't understand why I am now not getting HW at any time of the day (apart from it seems to be warm because I have turned that switch on but it is still not HOT yet albeit only after 1 hr)
Problem 2
As far as I am aware the Danfoss is simply a programmer and clock, telling my heating and DHW when it should and shouldn't be on. My underfloor heating is controlled separately by the Aube controllers of which there are many, located in every area where there is underfloor heating and these are also thermostat sensors too.
My radiators all have thermostatic vales on them but for the life of me I cannot find or see a wall thermostat to govern the overiding temperature.
It makes no sense to me not to have a wall stat as the heating will always be on during the time set ,leaving only the rads to reduce the ammount of heat they put out - Does that sound right and is it a common way of doing it?
Any and all help is much appreciated and I hope this long post all makes sense!!
TIA
Suds
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We have 3 bathrooms with showers, 1 of which is on the 1st floor, and the kitchen located in between - The boiler, OSO Cylinder and Danfoss Programmer are all located in the garage. What looks to me as the logical and most direct layout as per sitings or rooms is as follows:
1. Garage and cylinder
2. Bathroom 1 (ground floor)
3. Kitchen
4. Bathroom 2 (main house bathroom, ground floor)
5. Bathroom 3 (upstairs)
I have a few questions about this set up and really hope someone can help me please.
We moved in 3 weeks ago and the Hot water has mostly been ok, there are 4 of us living here (wife and 2 daughters) none of whom ever has less than a 10 minute shower. The water has always taken longer to reach bathrooms 2 & 3 and I presumed this is purely down to the distance it needs to travel through the pipes, possibly 30-40 meters.
Problem 1
The last day and a half we have not had any hot water. The timer and programmer shows the light saying that it is on for both heating and DHW but I can run the tap for ages in all rooms and still don't get any Hot water.
It could be that I am misunderstanding how to use the cylinder and controls properly as I have always had a combi system previously. Attached are photos showing the cylinder and controls on the wall and I believe the programmer is set up correctly and how we want it.
One thing to note - The switch that is labelled "water heater" has not always been on. I have just turned this on today as I thought it controlled one of the immersion elements and therefore essentially kept the heater on continuously - which goes against the point of having a timer and programmer... Is that correct? I started to think that the switch was the over riding power control for the cylinder but then we wouldn't have had hot water for 2 weeks if it was switched off would we??
The older style timer clock above the programmer is for a pool pump and filter system so shouldn't affect it at all.
There are 2 white cables coming from the cylinder that I can see and think they go to the wiring centre above the heater switch (for main power?) and into (or from) the water heater fused switch. The wiring centre is obviously wired to the programmer and the other white cable seen coming from it I believe goes to a motorised valve after the black circle thingy.
I am on an Economy 20 Plus electricity tariff and have the DHW set to come on at 05:00 for 3hrs, 15:00 for 2hrs and 19:00 for 2hrs to try to cope with our hot water needs.
How does the system work? As far as I understood it, there are 2 heating elements inside the cylinder - top and bottom - with the bottom one heating the majority of the water on the set programme. The top element then boosts the heat of the water when boost is used or automatically when the thermostats sense that it is not hot enough.
I don't understand why I am now not getting HW at any time of the day (apart from it seems to be warm because I have turned that switch on but it is still not HOT yet albeit only after 1 hr)
Problem 2
As far as I am aware the Danfoss is simply a programmer and clock, telling my heating and DHW when it should and shouldn't be on. My underfloor heating is controlled separately by the Aube controllers of which there are many, located in every area where there is underfloor heating and these are also thermostat sensors too.
My radiators all have thermostatic vales on them but for the life of me I cannot find or see a wall thermostat to govern the overiding temperature.
It makes no sense to me not to have a wall stat as the heating will always be on during the time set ,leaving only the rads to reduce the ammount of heat they put out - Does that sound right and is it a common way of doing it?
Any and all help is much appreciated and I hope this long post all makes sense!!
TIA
Suds
Attachments
