Radiator Valves
I am upgrading some of my radiators to meet the specifications of my heat loss survey
Working on the basis that Heat Pumps work more efficiently with a steady but high flow rate what is the advice on which type of radiator valves I should fit with the lowest flow losses?
Regular Lockshield valves seem to have very small internal chambers so I think they a very flow restrictive.
Are there ASHP system specific high flow rate radiator valves available as I can't see this mentioned in any of the tech specs on sellers websites?
Are TRVs at all necessary if house temp is set by a thermostat and Heat Pump modulation?
Hello, the high flow rate is not necessarily what you require; a relatively slow flow through the emitters allow the energy in the water to transfer to the area which it comes into contact with. The water enters the radiator at say 40 degrees and if running quickly, might emerge at the other end of the radiator at 38 degrees but... if running more slowly, it has more ‘dwelling time’ to dissipate that energy and emerge at perhaps 35 degrees. The general guideline for low temperature ASHP’s is a Delta T of 5 degrees. So the speed of flow ideally allows (with the right sized radiator) for a drop of 5 degrees across the radiator.
My system has a pump within the Daikin ASHP cabinet which works at variable speed and does its’ utmost to send the leaving water at one temperature and see a return of 5 degrees lower. This water enters a low loss header which has a secondary pump thus allowing a certain independence to set the flow rate to the emitters. I have spent some time adjusting this pump (Wilo Pico) for least losses (LLH’s are low-loss but not no-loss!) and as near as I can get to 5 degrees Delta T. Nothing is perfect, including my set up but I does me best! 😊 Regards, Toodles.
Toodles, he heats his home with cold draughts and cooks his food with magnets.
As a follow up on your question about lockshield valves etc. I think Heat Geeks did a YouTube presentation on the subject as there are now some (more expensive!) valve bodies available that have a more ‘swept path’ in the casting to improve flow and reduce turbulence. Regards, Toodles.
Toodles, he heats his home with cold draughts and cooks his food with magnets.
And as a follow-up to my follow-up, this is I think the presentation you might be interested to see.
Regards, Toodles.
Toodles, he heats his home with cold draughts and cooks his food with magnets.
- 26 Forums
- 2,102 Topics
- 46.2 K Posts
- 68 Online
- 3,388 Members
Join Us!
Latest Posts
-
RE: Who's your electricity provider and what's your tariff?
@old_scientist I found the switching between tariff jus...
By Toodles , 2 hours ago
-
RE: Plug and play solar. Thoughts?
Have a read of my previous posts on so-called Balcony S...
By Lucia , 5 hours ago
-
@editor @bart Hi, I can see a few problems with your in...
By Brendon Uys , 8 hours ago
-
RE: Ecodan consuming 100kwh per day in new build!!!
Well at least that solves the mystery of where the exce...
By JamesPa , 10 hours ago
-
RE: Compressor attempts start but fails - Nibe Fighter 2005 8kW
"To tell you the truth, I don't know if HAL is homicida...
By Scalextrix , 10 hours ago
-
RE: Location of hot water isolation valve on cylinder
@rossowheels if you isolate the water supply in it will...
By ASHP-BOBBA , 1 day ago
-
The Importance of Radiator Balancing for Efficient Heating: Introducing the Flow Regulating Valve
It’s fascinating to watch how low-temperature heating i...
By Mars , 1 day ago
-
RE: Servicing Hitachi HP in rural Somerset
I'd give GreenGenUK a call or email them: sales@greenge...
By Mars , 2 days ago
-
RE: Heating coming on when not required
I played with a max heating temp but there is a world o...
By JamesPa , 2 days ago
-
RE: Pressure drop Primary circuit
I've always regarded topping up heating systems as my j...
By JamesPa , 2 days ago
-
RE: Heat pump solutions and/or installer recommendations for France
I’d travel to France for work if you were struggling wi...
By Damon Blakemore , 2 days ago
-
RE: 5 Star Service from Havenwise
That's always a danger with any new good idea, @morgan....
By Majordennisbloodnok , 3 days ago
-
Have your say in the Renewable Heating Hub Awards
It’s time to celebrate the best (and call out the worst...
By Mars , 3 days ago
-
-
RE: Mitsubishi cycling while on chilled water output
@iaack yes there's no denying that cold air sinks! I s...
By downfield , 3 days ago
-
RE: Weather compensated secondary circuits with Biomass
@andycoo that flooring sounds ideal. Extra volume is ...
By Sune , 4 days ago
Members Online
No online members at the moment