Navien NCB 250-150

marcelt66

Hi everyone do I need recirculating pump on heating return line to drop pressure

I have 9 Radiators same time the pressure go up to 36 PSI

I Have 1 Taco 007-F5 On supply line

Thanks

GGross

You need an expansion tank. Can you show a pic of the piping as installed?

marcelt66

marcelt66

Thank you this it’s my setup

marcelt66

Hi I notice when the boilers runs for heat if I open hot water faucet pressure go up to 36 PSI and safety valve it,s opening making noise

Thank you

neilc

what year is the Navien? maybe heat exchanger is leaking thru(?)

marcelt66

2023

pedmec

Your missing a PRV and Backflow

GGross

Is that expansion tank piped to both the heating system and the DHW side but just valved off? what is the pressure on that expansion tank? it should say on the label somewhere the precharge, if someone changed it they would write it in sharpie or something. You also have a bunch of valves partially closed off for some reason?

marcelt66

Expansion tank it’s like 15 Psi from 40 PS

From tank it’s pipe to heating not to DHW

Those partials closed valve I did to reduce pressure in

Do I need to connect expansion tank to hot water supply to

Thanks

marcelt66

marcelt66

Thank you for all your help and suggestion this it’s what I did

Install Backflow and PRV

I Hope this will bring down the pressure

marcelt66

marcelt66

I did take out check valve and still the pressure go up to 36 PSI

I have to get Gordon Smith it’s licensed to contact NAVIEN

Thanks everyone

marcelt66

marcelt66

Hi everyone this it’s what I did so far so good

Install a PRV on Auto Feeder Inlet (Make-up-Water) and so far issue that I use to have it’s gone

Thank you everyone have a healthy and prosper new year