LG Therma V problem - rads only come on when UFH is calling for heat
We have a 12kw mono block pump running UFH in a number of downstairs rooms. It also runs radiators upstairs. The overall the system is controlled by the LG controller, the Heatmiser Wiring Centre (for UFH and DHW), the Heatmiser RF Switch (for Radiators), Heatmiser thermostats for each room downstairs and one for upstairs rads, and one main pump for flow. There seem to be 2 other pumps but I am not sure of their purpose.
My problem is that the upstairs radiators do not come on unless at least one room with UFH downstairs is creating demand so that the ASHP Controller is on. We did not request this, not that we given any options, and it seems to me to be either wrongly wired or it needs a second pump. Either way, are we wrong to think there should not be a dependency such as this built in ?
We have a similar issue, but the way we’ve overridden our on-off issues is to either set one of the thermostats that calls for heat to a high temperature your system will never hit or (which is what we’ve done) is switch our Salus controller for our thermostats to “always on” and not auto. This way the system is always calling for heat and with weather compensation on it should operate in the background.
If you have the Heatmiser app, you can set it to always on for your UFH which should then keep your rads running.
Pre-order: The Ultimate Guide to Heat Pumps
Subscribe and follow our Homeowners’ Q&A heat pump podcast
- 26 Forums
- 2,131 Topics
- 46.8 K Posts
- 24 Online
- 5,656 Members
Join Us!
Podcast Picks
Latest Posts
-
RE: Anyone still weathering it out with Agile?
Yes, but now try finding a working phone box….
By Majordennisbloodnok , 1 hour ago
-
RE: Thermostat for Ideal Logic Air with 3 zone support
No harm at all in plumbing it as 3 zones, I would have ...
By JamesPa , 4 hours ago
-
RE: ASHP heat output monitoring
@carlo I see there is a discussion in Facebook user gro...
By Tim441 , 9 hours ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
@editor @sandy I tried contacting them via Whatsapp b...
By brad , 1 day ago
-
RE: Flexi-Orb Heat Pump Scheme: A Game-Changer for the UK's Heat Pump Industry
MCS have set a potential trap in the new version of MCS...
By JamesPa , 1 day ago
-
RE: Who has a V2G EV installation
General comment on battery care... I guess if ev is on ...
By Tim441 , 2 days ago
-
RE: Heat Pump Servicing & Maintenance – Good Value or Rip-Off?
@old_scientist I have never cleaned the mag filter myse...
By Toodles , 2 days ago
-
@old_scientist like for like comparisons are almost imp...
By Tim441 , 2 days ago
-
RE: Who's your electricity provider and what's your tariff?
@old_scientist There is an option in the Tesla app that...
By Toodles , 2 days ago
-
RE: Mitsu Wireless Controller and MelCloud
On the FTC5 I think this requires the dip switch on the...
By Abernyte , 2 days ago
-
RE: Octopus Cosy & Octopus EV + bidirectional smart tariff, together. What, eh?
@old_scientist me too. Just installed my new heat pump ...
By Eliuccio , 4 days ago
-
RE: Is your heat pump insured?
Yup just spoke to Privilege to inform them of my impend...
By Scalextrix , 4 days ago
-
RE: Forum updates, announcements & issues
Just to keep everyone in the loop, as the site continue...
By Mars , 4 days ago
-
RE: Fast DHW setting on Midea (Clivet) heat pump
@simon-w, is this something you could potentially assis...
By Mars , 5 days ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
Fwiw I called my installer out for the first time a few...
By JamesPa , 5 days ago
-
RE: Long term efficiency degradation
@jamespa yes as I thought thanks. We have a reaso...
By Scalextrix , 5 days ago
-
RE: Sunamp Thermino Heat Battery
@jamespa A few days after the installation had been com...
By Toodles , 6 days ago
-
RE: Planning Permission May 2025
Fair enough. I have read the legislation and MCS020a ...
By JamesPa , 1 week ago
-
RE: How do I choose a single room MVHR to prevent losing heat in my bathroom ?
An update on the Heatsava. It is the most difficult thi...
By heat-pump-newbie , 1 week ago
-
RE: Renewables & Heat Pumps in the News
this document extensively describes (in a non-blame, ne...
By Judith , 1 week ago