Willis Heater for UFH

[LA3222]

Looking to gwt the UFH up and running now so I can slow time the ASHP etc. Looked through all the info on the Willis Heater setup and it seems fairly simple.

 

I've cobbled together a sketch drawing on the info found on the forum, if those in the know can have a look it is appreciated:

[Nickfromwales]

The link from manifold to manifold needs to be removed and dropped lower on the diagram eg so it is directly after the WH pump and returns straight back to the WH’s. That setup as shown would ‘boil’ the Willis heaters. 
You have also omitted the cold ( return ) connection to the mixing valve. 

[LA3222]

On 30/12/2020 at 23:16, Nickfromwales said:

The link from manifold to manifold needs to be removed and dropped lower on the diagram eg so it is directly after the WH pump and returns straight back to the WH’s. That setup as shown would ‘boil’ the Willis heaters. 
You have also omitted the cold ( return ) connection to the mixing valve. 

Thanks for the feedback @Nickfromwales, I've only just gotten around to looking at this again.

 

If those in the know would be so kind as to give some feedback, does the new drawing look better? TIA

 

 

[Gav_P]

Does it needs filter?

[AndyRP]

@LA3222 Thanks for your really clear diagrams on this thread. I'm currently scouring BuildHub to try and get my head round a simple UFH heating setup using Willis heaters for low energy refurb (total heat load about 2KW). Is the diagram above what you went with in the end? Has it worked well for you? 

[LA3222]

@AndyRP i used one willis and also put a filter in, will have a look to see where i put that in the circuit.

 

it was only a temporary setup for me to get the UFH working, to make sure the slab was dry before tiling and to find a loop as i needed to chisel into the slab to put a supply in for the island.

 

Worked fine getting heat into the slab and warming the house up. I wouldn't use it long term though as ASHP is my go to for UFH & DHW.