DIY install - Heat pump special parts

[eniacs]

I am just coming up to installing the pump itself and the main piping. I have already done the radiators and all new piping to the UVC install point.

 

I've ordered various parts and I am realising that some are restrictive, despite being 28mm entries, they heavily restrict flow. The Fernox 28mm sigma TF1 applied a 500mbar restriction to 100l/min flow whereas the heat pump version only restricts by 100mbar at the same flow. The filter i ordered was the wrong one so back it went.

 

I've so far bought only standard parts:

3 way valve - honeywell 28mm - interior looks restrictive, however its only over a very small distance.

Filter - heat pump version ordered - interior of non heat pump version was very restrictive quickly stepping down way below the ID of the 28mm pipe.

Main pump - ordered the grundfos UPS3 15-50/65 i think. It is the one suggested on their site and appears to produce the required flow according to the datasheets of heat pump and the pump.

Flexi pipe - ordered 28mm hoping this is ok

Freeze valve - again ordered 28mm hoping this is ok.

 

Am i missing anything, can anyone recommend better parts befor i cannot return them and find that they restrict flow too much!

 

 

[JohnMo]

Why would you want to flow 100l/min. That about 40kW?

 

What size heat pump are you installing? What flow rate do you need? How long are your pipe runs?

 

Piping sizing is a product of max allowable pressure drop and required flow rate.  28mm on 6kW heat pump will do loads of distance, but on a 12kW heat pump may be marginally on a short run. More information required.

 

I take you have radiators, hence the need for mag filter? For UFH there is nothing magnetic so a mag filter bring nothing to the table.

 

Expansion tank?

How are you filling the system and bleeding the system?

 

Are you not using the heat pumps circulation pump? Or are you installing a buffer in a 4 port configuration? If you do have a buffer it may be more beneficial to install in a 2 port configuration (as a volumiser), then you don't need a second circulation pump or take an efficiency hit on the heat pump.

 

Flex hoses from heat pump to solid pipe?

 

 

[eniacs]

1 hour ago, JohnMo said:

Why would you want to flow 100l/min. That about 40kW?

 

What size heat pump are you installing? What flow rate do you need? How long are your pipe runs?

 

Piping sizing is a product of max allowable pressure drop and required flow rate.  28mm on 6kW heat pump will do loads of distance, but on a 12kW heat pump may be marginally on a short run. More information required.

 

I take you have radiators, hence the need for mag filter? For UFH therecis nothing magnetic so a mag filter bring nothing to the table.

 

Expansion tank?

How are you filling the system and bleeding the system?

 

Are you not using the heat pumps circulation pump? Or are you installing a buffer in a 4 port configuration? If you do have a buffer it may be more beneficial to install in a 2 port configuration (as a volumiser), then you don't need a second circulation pump or take an efficiency hit on the heat pump.

 

Flex hoses from heat pump to solid pipe?

 

 

 

Hi John,

 

100l/min is just where the graph had an easy line to compare...

 

8.5kw mitsubishi, it lists 24l/min as flow rate. Pipe run max maybe 12m to furthest rad.

 

Good point, i actually only have 3 steel rads so if i changed those for alu wouldnt need a filter. I've got one now anyway.

 

Got a 24l expansion tank and filling system.

 

The mitsubishi doesnt have an internal pump

 

Yes flexi hoses listed got some 28mm 500mm versions for £50 from ebay