Baseboard Heating Issues, tried nearly everything

goblue2012

Hello, 

to start, I have checked every where on the internet and searched my issues with different phrasing trying to find the answers.

I bought my single story house in July of this year and it has a less than 5 year old boiler. There is one 2.5” copper pipe leaving the boiler that runs through the crawl space with 1” copper splitting off along the way for 3 base board heating loops. This is a series system with the finned heating. There are not individual pumps for these loops, it is all run off the main pump at the boiler. 2/3 of the loops have heat, the last 1” loop off the 2.5” pipe is cold with no circulation (based off me feeling it). There are bleeder valves on the above floor baseboards and Ive tried using those but they shoot water out, not air. The heat is controlled at a single thermostat controlling the temperature for all 3 loops. 

Before I start cutting pipe and replacing, does anyone have any ideas on what to do? 

I assume there is a blockage somewhere, but I don’t really know what to do to remedy that. 

hot_rod

Most often it is an air lock and it takes more than a bleeder to purge. Any valves on the branches or back at the booker yo purge a better flow? Some pics may help 

goblue2012

Jamie Hall

Your description of the piping and the problem don't relate to each other. If it is truly a series arrangement-- that is the water goes through each loop one after the other, with no way to bypass them -- you would get heat from all three. Can't help it (the last in line would be less, but shouldn't be much less).

So... how is it really piped? Particularly, any valves? That will determine how it can be purged; as @hot_rod says, that's most likely what is needed.

goblue2012

I don’t see any other valves on the lines other than what is near the boiler. The third picture shows the lines coming back, the one in the lower right is the blocked line. That converges with the one right next to it and has the yellow shut off valve shown in the 2nd picture

goblue2012

Jamie Hall said:

Your description of the piping and the problem don't relate to each other. If it is truly a series arrangement-- that is the water goes through each loop one after the other, with no way to bypass them -- you would get heat from all three. Can't help it (the last in line would be less, but shouldn't be much less). So... how is it really piped? Particularly, any valves? That will determine how it can be purged; as @hot_rod says, that's most likely what is needed.

By series I mean that the water has to come up to the surface in each loop. It can’t bypass a baseboard. 

goblue2012

Rough schematic of the piping and room setup every room except the boiler room is over crawlspace. Boiler room is on a slab

Jamie Hall

Ah. Thank you. Each loop is in series -- but the three loops are in parallel, with a supply main and a return main. Perhaps more important, the loop which isn't working is the longest one. Unless you can isolate that loop -- turn off the other two somehow -- you are going to have an awful time getting it purged, and that is what you need to do. With no valves on the takeoffs or returns to the mains, not sure how you are going to do that.

hot_rod

Looks like a 2 zone system, two thermostats? If so it could be one of those silver zone valves is not working, or the thermostat that operates it. They have a lever on them to manually force it open. Turn both thermostats up and try to latch both valves open.
Should look something like this.

EdTheHeaterMan

OK you need to purge the air


1. Find the pressure gauge and observe the operating pressure. it should be near 12 to 16 PSI (or near 35 feet)
2. You then increase the system pressure by lifting the "Fast-Fill" lever on the water feed valve (Pressure reducing valve). until it gets to about 25 PSI (or about 60 feet) put the fast-fill lever back to the automatic position once the pressure is at 25.
3. You then connect a garden hose to the purge drain as indicated in the picture in green.
4. Then you close the isolation valve with the white handle then close one of the isolation valves from the other picture with the screwdriver slot
5. Open the drain valve and let the high-pressure water force the air out of the pipes/baseboard radiators/convectors and what have you. (A drain is better than a bucket. the bucket will fill rather quickly and need to be dumped several times.) Keep the auto-feed manual handle open whenever the pressure drops below 25 PSI put the manual valve handle back to automatic when the pressure climbs above 25 psi
6. After the air is forced out you will see a constant flow of water with a bubble or two (but mostly water) switch the screwdriver slot valves to purge the other loop.
7. After both loops have been purged before you close the drain valve... set the auto-feed valve back to automated (12 PSI.) and let the system pressure drop to 12 before closing the drain valve.
8. You can now do the same procedure for the other zone with the same procedure except there are no isolation valves since there is only one loop for that zone.
9. when you have finished put all the valves in steps 1 thru 7 back to the original operating position.
10. Now start the system and see if the heat flows.

EdTheHeaterMan

I could not help but see the zone valve on the pipes. are you sure there are no other thermostats?

Before you do the air purge thing. try to open the manual tab on the zone valve to see if the heat will flow.


here are two different zone valves with the manual lever in the open position.

goblue2012

🤦🏻‍♂️It is on another thermostat

EdTheHeaterMan

goblue2012 said:

🤦🏻‍♂️It is on another thermostat

Did that solve it?

EdTheHeaterMan

Print out the instructions I sent if you ever need to purge air.
The zone valves also need to be open for purging. Add the to step 1

goblue2012

It solved it! Thank you for the help!

aperson

Funny.

Big Ed_4

Parallel single baseboard zone system . Surprised zone valves were not added yet...