Purging Questions on Radiant Heating System

Kerch5

Hello and good afternoon,

After watching multiple videos and conducting multiple searches i have ended up on the forum looking for a little help.

Long story short we bought a new house with a radiant heating system, looks to be 4 zones with 3 still operational. Soon after moving in one zones pipe busted. To my suprise the baseboard registers were hooked up to the basment zone. Plumbers showed up, fixed the broken pipe and thus my basment baseboard heat started working for the first time! But, a week later now I have lost my living room radiant heat. I'm assuming it's a air pocket.

The reason why is i can confirm the system is calling for the pump to be on and that the pump is running and was working before hand. I also confirmed the block is warm, aka the bottom distribution block in the picture. None of the tops are warm.

I have tried figuring out how to purge it, but my system of course seems a little different then most videos I've watched so I was hoping someone with a little more experience could help me out. I did use the key bleeder on the top there and let it run for a bit but instant water but cold. My fill seems to be interesting as well before the circulator so I'm not sure i should flip it to increase pressure.

Attached are pictures of the whole system and then the zones distribution block for some refrence. If you look close you can see arrows of flow. The zone in question doesn't have a valve to close like the others on top. The system in question is the bottom Taco pump, T2. That's the feed. The return for it's the first one on the top called great room.

I'll also add I'm in southern wi so it's 40s out, all zones reaching desired temps and this one is not. Also used to feel the warmth on the feet and no longer do.

Any and all help is greatly appreciated!

Thanks!

Kerch5

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Pictures didn't load the first time it looks like

Kerch5

Here's the other thing that makes no sense to me, if you look at those 3 valves in the 2nd picture why is the first one open, wouldn't the water take the shortest route from the circulator and thus take flow away from the 3 zones?

DCContrarian

Just comment — it's much easier for others to view the photos if you insert them inline — the picture icon — rather than as attachments — the paper clip.

Kerch5

I have changed them as requested. Thanks

hot_rod

the two ball valves in the upper right of the pic, with two hose valves next to them are for purging those two zones

Hose valves at the ends of the manifolds to purge those loops

psb75

Two, upper green circulators need to be oriented properly for longevity. There looks to be plenty of locations for purging as hot_rod mentioned.

Kerch5

Thanks for the reply.

Correct, the one I'm questioning is the furthest left as that's the one not heating up. I have used the bleed valve on that one and drained some and it made no difference. The other ones make life a lot easier haha.

leonz

speaking as a homeowner, I guess I have to ask, where is the air purger?

I do not see an air scoop or automatic air vent anywhere in that mess of bad piping.

GroundUp

The reason they have that "bypass" in there is because the system is piped wrong and it would deadhead the boiler without a bypass. For starters, the Taco circ in question is mounted wrong and may very well be at the end of its life because of this (hence why the lower two have already been replaced), causing your lack of flow. There really isn't a good way to purge air from that zone without cutting in purge valves like are present on the other two zones (likely done when the circs were replaced for the same reason).

Frankly, the best would be to cut the whole thing out and start over with correct piping and one central purge station. That's not likely to be in the desired budget, so the cheap and simple option is to verify operation of that Taco and then either reorient or replace it, as well as add purge valves like are on the other two zones.

Kerch5

Thank you for the reply!

Can you expand on the Taco circulator, are you talking the the one right next to the fill valve or you talking the one that feeds the specific zone?

I'm assuming this was for a wood burning boiler to start with and then when the house was added on in the early 2000s they added in floor heat to the new additions and switched to this system. Explains the "crazy" piping.

I'm with ya on adding the purge valves like the others zones.

Thanks again!

GroundUp

"The Taco circ in question" meaning the one pushing the loop that's not flowing AKA the second from the top as you've described. Motors should be horizontal like the other three, not vertical.

Kerch5

Gotcha, thanks!

Sounds like a have one **** of a system.