UFH boiler call problem

[Deleted member 126459]

Hi,

I have a strange problem in my recently purchased property. I hope someone can shed some light on it.

In a nutshell, when a thermostat causes the underfloor heating pump to run, the boiler does not provide heat unless it happens to be switched on manually or by the boiler timer.

It is not an option to leave the CH set to permanently on at the boiler time – although there is no heating other than the, UFH, the boiler pump runs constantly in this state.

For background, it's an 8-year old pressurised system comprising:

• a Baxi Megaflo 2 System Compact GA Range condensing boiler (with integral pump), controlled by a basic Newlec timer
• a hot water cylinder with expansion tank with a simple thermostat
• an Uponor water underfloor heating system with a 9-way manifold and pump controlled by an Uponor I-36 timer and C-35 controller
• 6 x simple Uponor manual dial hardwired thermostats

I've had a look at the UFH control panel and there is no wiring from the boiler relay (and it won't be easy to add, as the UFH manifold is far from the boiler in the property).

Is it possible for the configuration at the boiler to automatically detect the flow when the UFH pump starts, without a wired connection? And if so, any idea why it isn't doing so?

Many thanks for any steer!

Andrew

 

[ShaunCorbs]

Sounds like it’s needs wiring properly and a new cable running

 

[SimonG]

Wiring issue or missing 2 port valve.

 

[Basher]

If you are focussing on the difficulty of running wires, an RF/wireless switch can be used in place of a physical cable.

 

[Deleted member 126459]

Hi ShaunCorbs, SimonG & Basher – many thanks, all, for the suggestions.

Basher – that sounds like the way to go if possible as the cable route would require a lot of drywall cutting and repairs etc.. Any suggestions for suitable components, ideally that could simply be added to the existing kit?

(I would ideally like to upgrade to Heatmiser kit, which I know can do this, but that's a pricey job replacing lots of components, and they seem forever out of stock of the appropriate thermostats.)

 

[Basher]

Basher – that sounds like the way to go if possible as the cable route would require a lot of drywall cutting and repairs etc.. Any suggestions for suitable components, ideally that could simply be added to the existing kit?

(I would ideally like to upgrade to Heatmiser kit, which I know can do this, but that's a pricey job replacing lots of components, and they seem forever out of stock of the appropriate thermostats.)

This is an example:

https://salus-controls.com/files/Main-Switch-Flyer-UK-V005.pdf

The above components would need to be housed in suitable enclosures.

Or this "mains-link" solution (which has been suggested before on this forum)

MAINSLINK 5KM WIRELESS MAINS TO MAINS 230VAC LINK

MAINSLINK is a plug and play solution to replace a switched live cable. When 230Vac “LIVE” is input to the transmitter; the receiver provides a 230Vac “LIVE” switched output at its screw terminals. When a cable run is awkward or expensive to achieve, the MAINSLINK can be used, saving time and...

www.rfsolutions.co.uk

 

[Deleted member 126459]

Thanks very much indeed, Basher. I'll explore further and see if I can get it sorted. Cheers.