Wiring diagram needed please

[roseyp]

Hi all,
need some help or pointers please
father in law has a system that I am upgrading. He doesn't have a room stat or tank stat.
current set up is a baxi back boiler with a grundfos ups2 pump, 3 port Honeywell valve, danfos 3020p.

so heating works and hot water works but both together, he can't have 1 or the other.
i have ordered a salus rf300 room stat and a wired tank stat. The system is y plan.
Looking at diagrams I can find they require a heating satisfied signal which the 3020p doesn't have

so should I use a sundial wiring system or do i need a big terminal block and a someone to sketch it out !!
any pointer ?
roseyp

 

[albatross]

You have two options:
1. Replace the 3020 with a new clock that does give a HW off/satisfied wire.
2. Keep the 3020, just have a satisfied from the cylinder thermostat. With this you will have to turn both heating and HW on at the clock but the HW will turn itself off when the cylinder thermostat is satisfied.

 

[roseyp]

Option 2 is what I need, but in reverse !! The timer is set for 2 times daily, but only need dhw this time of year. I thought with introduction of a room and cylinder stat I could influence the valve and turn off the ch when either satisfied or not needed. At present the boiler setting (1-9) controls the tank temperature !
Roseyp

 

[albatross]

Swap everything for a Drayton T720M pack 3.
https://www.plumbnation.co.uk/site/drayton-mitime-rf-pack-3-t720m/

 

[albatross]

Can he not get HW only at the moment?
He should be able to with what he has. If not then there is a problem that needs rectifying first.

 

[roseyp]

That is exactly the problem. When the programmer is in dhw mode only, the rads also heat up and lots of resistance in the override on the 3 way valve. Don't know if it had always been that way or just started. But when I looked at the system it was evident that it is primitive !! So only the boiler temp control governs the system, and it's either all or nothing for dhw and ch. I think it will be easier to replace the lot but he likes the 3020p as its easy to use

 

[albatross]

You have a fault then, maybe the honeywell valve is passing or the system is piped up wrong.
There should be a lot of resistance on the lever when there is no demand from the heating side.

 

[Aquazone]

Replace the programmer with a Drayton SM2. It's not my preferred choice of programmer, but I tend to use it in situations like you have, where elderly people don't want all singing and dancing 7 day programmable one.

Probably need to look at 3 port valve as well, as has been said previously, sounds like it's passing.

 

[roseyp]

I think that the valve is passing but was aiming to get it to work if the wiring was incorrect as I suspect that as the 3020 only has dhw on and ch on then nothing is showing as satisfied. So plan is to replace programmer, 3 port valve, add a wireless room stat, add a tank stat all wired to a sundial wiring hub, and probably a good flush while I am there.
Thanks for advice and help
Roseyp

 

[albatross]

Honeywell 3 port valve brass body 22mm diverter | eBay

DRAYTON MiTIME PACK 2 PROGRAMMER WIRELESS RF THERMOSTAT T720R | eBay

Danfoss FP715Si 2 Channel Programmer 24HR/5-2/7 Day | eBay

Sunvic SunPro 2000 2 Channel Programmer heating timer clock | eBay

Some of these may help you.

 

[stevetheplumber]

sounds like the existing threeway is buggered