Central heating not circulating after New Navien Combi fitted to Santon Premier system.

[JohnHuson]

Should be after the llh

I hope there’s additional expansion tank / tanks ?

Thanks Shaun but I did not get the last word meaning? iid?

 

[ShaunCorbs]

Sounds like you need to separate the system. Also is the old boiler a non condenser @ShaunCorbs and the rads possibly ∆T 60?

Yep

Low loss header as condensing boilers don’t like older systems tbh I would fit a plate heat exchanger to save the new boiler as I doubt they cleaned the system

 

[JohnHuson]

Sounds like you need to separate the system. Also is the old boiler a non condenser @ShaunCorbs and the rads possibly ∆T 60?

No, the old boiler was a 20 year old Ideal Concord CX40 floor standing unvented.

 

[JohnHuson]

Are you in travelling distance of Chester?

 

[ShaunCorbs]

About 10 miles away but I booked up sorry

 

[SJB060685]

Yep

Low loss header

Then if the old boiler was running at ∆T 11°c the pump would of been capable of the higher flow rate and pressure required to overcome index circuit.
Sounds like this needs a low loss header and suitably sized secondary pump. The secondary side pipework will be ok in size but the new boiler internal pump isn't capable.
Alarming really as the installer really should have considered this

 

[ShaunCorbs]

Then if the old boiler was running at ∆T 11°c the pump would of been capable of the higher flow rate and pressure required to overcome index circuit.
Sounds like this needs a low loss header and suitably sized secondary pump. The secondary side pipework will be ok in size but the new boiler internal pump isn't capable.
Alarming really as the installer really should have considered this

Makes you laugh tho they thought a 15-70 would do 2” pipework it’s the state of the industry atm either people don’t care or they don’t know chances are it was a 25-80 or 32-80

Was he even commercially qualified to work on the install

 

[JohnHuson]

Then if the old boiler was running at ∆T 11°c the pump would of been capable of the higher flow rate and pressure required to overcome index circuit.
Sounds like this needs a low loss header and suitably sized secondary pump. The secondary side pipework will be ok in size but the new boiler internal pump isn't capable.
Alarming really as the installer really should have considered this

I agree. The boiler developed a leak from the heat exchanger seal 9 weeks in and charged 200 quid to do a 35
minute job under guarantee. Now they do not want to know.

 

[ShaunCorbs]

I agree. The boiler developed a leak from the heat exchanger seal 9 weeks in and charged 200 quid to do a 35
minute job under guarantee. Now they do not want to know.

Didn’t they call the manufacturer out ?

 

[JohnHuson]

No and the customer got a gas certificate but the commissioning report was not completed.