central heating nightmare

[aaron1591]

Hi I wonder if someone can help me I'm having trouble getting my heating and hot water to come on at the same time I've recently replaced the pump and the 3 port valve

The old 3 port valve was a Honeywell mid position v4073a
And the new one is siemens 3pmp-v22 but i cant seem to get it to mid position my setup is as follows

Programmer- potterton ep2000
Cyclinder stat-switchmaster
Boiler potterton netaheat
Pump- grundfos
M/v- siemens 3pmp-v22

The wiring goes like this

Boiler
Brown-d
Blue-n
Earth-e

Motorised valve
Neutral - neutral
Earth-earth
White-c
Grey-1
Orange-a

Main power
Brown-live
Blue-neutral block
Earth- earth

Cyclinder stat
Blue-1
Earth-a
Live-3

Pump
Neutral-n
Earth-earth
Live-d

I'm also wanting to ad a room stat which has
No
Com
Nc

Where do I wire these to?

And finally the 3port valve instructions say to get mid position wire as followed

Blue-2
White-5(without room stat)
Grey-7
Orange-8
Earth-3

With room stat wire
White-6

 

[Dan Robinson]

I'm out

 

[GavThePlumber]

Wire it in correctly.

 

[aaron1591]

That's what I'm asking how is correctly?

 

[Gasguru]

If you thought the mid-pos valve was faulty you should have bought another Honeywell and just swapped the innards and actuator.

EP timeclocks do weird things so never rule that out.

Pin number designations on diagrams and system components are not standard...each manufacturer has their own system.

Appears you've now got a complete mess, get yourself a Y plan diagram and start from there...remembering to ignore pin numbers.

Also remember that a significant number of Y plan mid-pos valve systems have never worked properly from day one....most common fault being a missing DHW OFF from the clock.

 

[MANDATE]

when you had the old valve in, did it operate correctly?.

The cylinder stat is like a two way switch (3 terminals). The common terminal is fed from the programmers HW ON terminal,which leaves two more terminals.
One is the 'unsatisfied ' terminal where wire goes to boiler.
When HW is satisfied power is diverted to the 'satisfied' terminal and a wire from this terminal goes to the valves grey wire.
From information given your cylinder stat shows 3 wires but one is earth, which would indicate either a wire missing or not the correct type of stat.
So that's something that needs clarifying.