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.

 

[SJB060685]

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.

That would of been a warranty job and the manufacturer liable for payment, not you!
Unfortunately to rectify this is going to cost more and the situation clearly demonstrates the installer doesn't understand the principles.

 

[ShaunCorbs]

Time to get a solicitor involved

 

[JohnHuson]

That would of been a warranty job and the manufacturer liable for payment, not you!
Unfortunately to rectify this is going to cost more and the situation clearly demonstrates the installer doesn't understand the principles.

This customer is prepared to spend money in excess of what was paid for what should have been paid under
warranty in a small claims court.

 

[JohnHuson]

So where in the system should the extra push pump be located please?

 

[ShaunCorbs]

Where the old boiler pump was

 

[SJB060685]

I think between us we have arrived at the problem. My concern now though is as I mentioned above are the existing rads at ∆T 60°c, if so the flow temperature will need to be around 90°c to give a rad MWT temperature of 80°c and full out put.

 

[JohnHuson]

I think between us we have arrived at the problem. My concern now though is as I mentioned above are the existing rads at ∆T 60°c, if so the flow temperature will need to be around 90°c to give a rad MWT temperature of 80°c and full out put.

yes hat makes sense but I have to get the water around the system in the first place.

 

[JohnHuson]

The boiler is capable enough so where do I install a secondary pump?

 

[SJB060685]

yes hat makes sense but I have to get the water around the system in the first place.

Yes I agree completely. However I suggest separation, pumps in series is not always going to work.

 

[ShaunCorbs]

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