Need help. Navien 180 novice user

[Csvt18]

Hello,

we moved into a house with hydronic baseboards last year. 3 zones. Heated by a navien combi boiler. 180e model. I have confirmed there are no bleeder screws on any of the baseboard tubes. I checked everyone. I have attached pics of our set up. On one of the pics, there is a spigot looking drain valve (red handle) towards bottom of the return line on the boiler side. Could this be the bleeder the installer put in? I’m confused as to what it is.

it’s not the overflow we have the pressure relief coming off from the top of the tank

so my questions are,

1. What is that spigot drain valve ?

2. Does the pressure relief ( coming off top of tank) need to manually operated at all ever?

 

[John Gayewski]

The relief doesn't need anything. You could check it to make sure it opens and closes properly, but a lot of times a chunk of something will get stuck in it and it'll drip. In that case it needs either thoroughly cleaned or replaced. Best to just leave it alone.

The boiler drain is to fill or drain your system.

 

[Sponsor]

 

[Csvt18]

The relief doesn't need anything. You could check it to make sure it opens and closes properly, but a lot of times a chunk of something will get stuck in it and it'll drip. In that case it needs either thoroughly cleaned or replaced. Best to just leave it alone.

The boiler drain is to fill or drain your system.

I’m guessing that spigot with the red handle is what your referring to as the boiler drain? What would the system need draining for?

 

[Fitter30]

That big brass fitting on top of the grey expansion tank is your air eliminator. Should have a brand and model number on it to download a install manual.

 

[Csvt18]

That big brass fitting on top of the grey expansion tank is your air eliminator. Should have a brand and model number on it to download a install manual.

yeah I loosened the little knob on it and a bit of air purged. It was tight. I read to keep it a quarter turn loose to auto purge.

 

[John Gayewski]

I’m guessing that spigot with the red handle is what your referring to as the boiler drain? What would the system need draining for?

To fix it it needs to be drained at times.

 

[John Gayewski]

Your system needs yearly maintenance. You need to find a local company to do this for you to keep your warranty. I recommend you to so.

 

[Csvt18]

Also you can’t see it but my intake pipe is through an unused chimney right next to the water heater. And the exhaust is ran to the front wall of house and out.

is this an issue with the intake being in a confined space, and in a totally different area than the exhaust?

most installs I’ve seen have the intake and exhaust piping close to each other exiting the house.

 

[Fitter30]

Guess u have a npe 180 look at page 30 of the install manual. This heater can use a single pipe instead of the two. Two would be better piped both out the same side of the house. This is a safe site.
https://www.manualslib.com/manual/1055596/Navien-Npe-180a.html

 

[Csvt18]

Anyone have any idea why my supply heat water and return water are mixing ? If you look at the pic showing that red handled valve you can see there’s a quarter turn yellow handle valve. Shouldn’t that be higher and turned off so they don’t mix?

 

[John Gayewski]

Anyone have any idea why my supply heat water and return water are mixing ? If you look at the pic showing that red handled valve you can see there’s a quarter turn yellow handle valve. Shouldn’t that be higher and turned off so they don’t mix?

A tankless heater heats water so fast that it would cycle on and off all of the time if they didn't mix. Every time your heater starts it wastes energy. Thr colder the water entering the heater the longer it can run and keep thr efficiency up.

Some hearing zones can only take water of a certain temp and it's sometimes made easier and more efficient to mix.

These are some reasons to mix. They are good reasons. If you look online you can find common piping schematics given by your manufacturer and compare it tipp what you have.

Are you having problems with your system? If not I'm not sure where thr question came from?

 

[Csvt18]

A tankless heater heats water so fast that it would cycle on and off all of the time if they didn't mix. Every time your heater starts it wastes energy. Thr colder the water entering the heater the longer it can run and keep thr efficiency up.

Some hearing zones can only take water of a certain temp and it's sometimes made easier and more efficient to mix.

These are some reasons to mix. They are good reasons. If you look online you can find common piping schematics given by your manufacturer and compare it tipp what you have.

Are you having problems with your system? If not I'm not sure where thr question came from?

im just very detail orientated and study things. I was looking at the pipe schematic today. I turned down my boiler temp from 180f to 155f and I noticed it runs longer but smoother. No on and off multiple times like it used too. It doesn’t have trouble reaching set point in thermostat either.

I think it was set way to high at 180 so it would reach temp to quickly and shut down. Then restart id say 5-6 times an hour.

 

[John Gayewski]

im just very detail orientated and study things. I was looking at the pipe schematic today. I turned down my boiler temp from 180f to 155f and I noticed it runs longer but smoother. No on and off multiple times like it used too. It doesn’t have trouble reaching set point in thermostat either.

I think it was set way to high at 180 so it would reach temp to quickly and shut down. Then restart id say 5-6 times an hour.

Yeah 5 or 6 times an hour is too much.

 

[John Gayewski]

im just very detail orientated and study things. I was looking at the pipe schematic today. I turned down my boiler temp from 180f to 155f and I noticed it runs longer but smoother. No on and off multiple times like it used too. It doesn’t have trouble reaching set point in thermostat either.

I think it was set way to high at 180 so it would reach temp to quickly and shut down. Then restart id say 5-6 times an hour.

There are many many schematics and they have evolved over the years. I haven't really looked at what you got going on, but it should be very close to a variation of one from the manufacturer. They usually provide a host of options for different setups.

 

[Fitter30]

Npe180a they make a add on controller a snap on board that kdo-a100 with a outdoor sensor can add outdoor reset that varies the heating setpoint based on outdoor temperature.

 

[Csvt18]

Ok what about this. I noticed my return temps are higher than they should be. Supply is 155f return anywhere from 142-149f. I have a grundfos 15-58 that pumps to all 3 zones. It’s on low. I think it’s to powerful/oversized for my house. 2100sq ft tri level.

the upstairs which is right over the boiler in the basement heats up quickly where as the main level (the biggest area) heats up not as quickly. Return temps for both are as stated.

would closing those quarter turn valves, located after return valves in top pic, closing those some to “throttle down” water help lower return temps?

 

[Fitter30]

Normal design per zone is 20* difference between supply and return. Measure how many feet of fin tube per zone and pipe size. 7/8" measurement outside is 3 /4" copper pipe. 5/8" is 1 /2"

 

[John Gayewski]

The delta t is any number any person wants it to be. It's picked from thin air. Radiant floors people like a delta of 10 or less. 15 t0 20 for other emitters.

This is mainly about comfort and where your thermostat is.

Radiant floors for example, most people don't want one part if a room tipp be 20 degrees colder than the other part of the same room.

 

[Csvt18]

The delta t is any number any person wants it to be. It's picked from thin air. Radiant floors people like a delta of 10 or less. 15 t0 20 for other emitters.

This is mainly about comfort and where your thermostat is.

Radiant floors for example, most people don't want one part if a room tipp be 20 degrees colder than the other part of the same room.

can you change the speed of a grundfos pump when it’s on and running? Gonna try speed 2.

 

[John Gayewski]

can you change the speed of a grundfos pump when it’s on and running? Gonna try speed 2.

Yes