Search with Wattson

Notifications

Clear all

Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!

Vaillant - Downstairs radiators not getting warm

samiebon1 · 2025-01-22T09:35:50Z

Had a Vaillant 5kW installed last week and upstairs is getting up to temp ok, but all the downstairs radiators are luke warm at best. I've tried balancing but no such luck. They are column rads, but I've got columns upstairs which are getting warm. A couple of thoughts/questions - could this be resolved by topping up the system pressure more (analogue dial says 1.5, digital says 1.2); could I modify the remaining feed head setting (currently 900); or... Something else? Also, my DHW doesn't seem to be getting up to temp. It has a 3 hour period over night to charge and I've set the offset to 15K which I thought would be enough. Any suggestions? Thanks all!

Page 2 / 2 Prev

Air Source Heat Pumps (ASHPs)

Last Post by Judith 1 year ago

16 Posts

6 Users

2 Reactions

3,458 Views

RSS

samiebon1

(@samiebon1)

Eminent Member Member

Joined: 2 years ago

Posts: 25

Topic starter 22/01/2025 9:41 pm

@jamespa thanks James! Ive read through the manuals and found the Eco DHW setting on the Heat Pump controller. I've set it to Manual to see if that gives me the energy in tonight charge cycle.

ReplyQuote

Judith

(@judith)

Prominent Member Member

Joined: 3 years ago

Posts: 537

22/01/2025 11:18 pm

@samiebon1 our DHW gets to 48C with a heating temp of ~55C within ~ 45mins but it’s not usually empty (residual ~35 in bottom third of tank).

The layout of our house meant that some upstairs radiators had to be virtually off to ensure the flow went on to downstairs or else the bedroom radiator took all the water.

2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with SCOP >4) open system operating on WC

ReplyQuote

samiebon1

(@samiebon1)

Eminent Member Member

Joined: 2 years ago

Posts: 25

Topic starter 23/01/2025 8:12 am

@judith did you manage to solve heating the downstairs? Or are you upstairs still off? ... Or when you mean 'off' do you mean the lock shields are only just open? 😄

ReplyQuote

Judith

(@judith)

Prominent Member Member

Joined: 3 years ago

Posts: 537

23/01/2025 8:50 am

@samiebon1

When adjusting lockshields its worth bearing in mind that some have a tiny range over which the adjustment makes any difference. Sometimes half a turn or less takes it from fully closed to fully open. This makes getting it 'right' quite tricky.

If you want to know more about this view Heat Geek on 'valve authority'.

2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with SCOP >4) open system operating on WC

ReplyQuote