How to run 2 zones off a single pump?

[jason61c]

I've fitted a heatmiser uh4

https://www.underfloorheating.co.uk/Files/127465/U...

3 UFH zones

hot water

2 radiator zones

Where it falls apart is that its designed for one radiator zone only, i've got 2, shared pump. If I use the zone valve to trigger the pump, the voltage hits the uh4 and opens the other zone valve, and vice versa.

1 neostat ultra
4 v2's
1 hot water

How can I prevent this? been scratching my head over it!

[jason61c]

I think its more an issue with the above setup.

Its the radiators zones that's causing the issue.

[jason61c]

There’s zero issue with the Heatmiser.

Simple solution is to fit the spare pump I have so both radiator zones are pumped independently.

[jason61c]

fatboy b said:

Their software is a big issue. After a month of back and forth with their helpdesk over it, they refunded me.

A netatmo will handle what you want to do.

It seems to work well for me. the netamo is about 3-4 times the total cost for what I need.

[jason61c]

silversurfer1 said:

Looks to me like you need a UH8 it has capacity for more zones.

You could fit a separate programmer for the other heating zone, id not be adding another pump

ss

the uh8 still only has one radiator zone, just more UFH zones.

[jason61c]

Rickyy said:

Do away with the heatmiser controlling the heating and hot water zone valves. Wire the system as a normal S-plan (albeit with more zones). 2x radiator zone valves, water zone valve and UFH zone valve

It would seem that when there is a demand for heat from the UFH, LS and LR become a closed switch. I would put a permanent live to LS and connect LR to the brown wire of the UFH zone valve. That way, all it's doing is opening the zone valve, the microswitch inside (grey and orange) switches the boiler and pump on, without powering any other zone valves.

There's a dedicated output for the UFH stuff that doesn't trigger the radiator pumps or valves. so UFH is controlled(own pump), radiator zone(own pump) and hot water(own pump).

I confused it by adding a second radiator zone, as using single pump would trigger the other(wrong) zone valve due to the way its wired.

I've fixed it by adding a spare pump I had. Really works well now.