Watson524
Member
Hi all,
In my mom's house (currently unoccupied but myself or my husband is up there 4 to 5 times a week to check on things), there's a hot water oil fired boiler with 3 zones of hot water baseboard, 1 zone for hot water and 1 zone for the radiant heat in the master bathroom.
Some things about the system: Circulator pumps are on the "push" side of the boiler and are all Taco 1/25hp standard pumps. On the radiant zone, there's a mixing valve that you use to temper in return water so that it's not sending fully heated boiler water into the radiant tubing. The main living area baseboard zone is set to primary in the Taco relay panel. We have a spirovent coming off the boiler above the expansion tank before it branches out to each of the circulator pumps/zones. Because one zone in the sunroom is insulated underneath but still on piers, there's glycol in the system.
My husband went up yesterday and there was steaming hot water pouring from one of the Taco circulators between the body and the impeller part (i.e. not that a flange gasket went bad). So needless to say, I need to get glycol back into the system but that's something I can handle.
We shut the system down and luckily a big box store had the Taco pump we needed so we replaced it no problem. I have isolation valves above the circulator pumps, one shut off valve just after the expansion tank before it goes into the branches of the circ pumps (I wish I had individual valves below pumps too vs just above on the outlet side). One the return side, I have valves above and below the hose bibs. When we brought the system back online, I had all the thermos turned way back and all valves closed. We made sure the auto fill valve got things up to the right pressure and that all was fine. The boiler had most of the pressure already in it since the circs are slightly above the boiler, just made the well pump run to keep up with the autofill I suppose. Once the boiler was at pressure based on the gauge, I opened the 3 valves (1 on outgoing side and 2 on return side) and then made that zone's thermo call for heat. Once the return side came back hot, I shut off those valves and moved on to the next zone. On the first 2 baseboard zones, I could actually hear the spirovent piss out a bit of air (good!). I did the 3 baseboard zones one by one, then did the hot water zone, then did the radiant zone last because I knew it'd take the longest.
It came back hot and so we set the t-stats to their normal (about 120 on the hot water tank and 60 on the wall t-stats, but 70 on the t-stat for the radiant zone because I wanted to make sure that got up to warm). The issue I'm having is that the radiant zone today, tho calling for heat, doesn't seem to be getting warm in the bathroom itself. On the return line for that zone, it comes back and branches, one side goes to the return side of the boiler (not feeling warm there like it did when we first started it up), and then the other side branches into a mixing valve on the circ pump side which does feel reasonably warm. The gauge in the pipe just above the circ pump is reading 150 (I think the boiler max is set to 200). We have had an issue before in bitter cold where if the primary keeps calling for heat, the radiant just doesn't get to keep up. For that reason, I turned down the t-stats to 55 to see what happens but..........
(And I apologize for the long post but I wanted to give as many details as possible)
Couple questions: Should I adjust the mixing valve to take the temp going to that zone up a bit (say 180)? Is it possible that maybe there is an airlock in the radiant floor zone even tho there wasn't before and the spirovent isn't handling it? It just seems weird that not 5' from the return's drain spigot, it's warm and warm over to the mixing valve UNLESS (and I don't remember if hot goes to cold or vice versa, it's feeling warm up in there because the boiler water is pushing up and not that it's really warm from the return water). I did NOT check the pressure in the expansion tank and maybe I should. I feel like we've had similar issues before and tho there doesn't appear to be an air leak, it needed a few pounds. maybe the radiant zone just needs more help? I was thinking maybe that zone needs a bigger circ pump but the house was built 16 years ago and except for a few incidents, it's always been fine so I'm guessing not.
Thanks in advance for any insite you can offer.
In my mom's house (currently unoccupied but myself or my husband is up there 4 to 5 times a week to check on things), there's a hot water oil fired boiler with 3 zones of hot water baseboard, 1 zone for hot water and 1 zone for the radiant heat in the master bathroom.
Some things about the system: Circulator pumps are on the "push" side of the boiler and are all Taco 1/25hp standard pumps. On the radiant zone, there's a mixing valve that you use to temper in return water so that it's not sending fully heated boiler water into the radiant tubing. The main living area baseboard zone is set to primary in the Taco relay panel. We have a spirovent coming off the boiler above the expansion tank before it branches out to each of the circulator pumps/zones. Because one zone in the sunroom is insulated underneath but still on piers, there's glycol in the system.
My husband went up yesterday and there was steaming hot water pouring from one of the Taco circulators between the body and the impeller part (i.e. not that a flange gasket went bad). So needless to say, I need to get glycol back into the system but that's something I can handle.
We shut the system down and luckily a big box store had the Taco pump we needed so we replaced it no problem. I have isolation valves above the circulator pumps, one shut off valve just after the expansion tank before it goes into the branches of the circ pumps (I wish I had individual valves below pumps too vs just above on the outlet side). One the return side, I have valves above and below the hose bibs. When we brought the system back online, I had all the thermos turned way back and all valves closed. We made sure the auto fill valve got things up to the right pressure and that all was fine. The boiler had most of the pressure already in it since the circs are slightly above the boiler, just made the well pump run to keep up with the autofill I suppose. Once the boiler was at pressure based on the gauge, I opened the 3 valves (1 on outgoing side and 2 on return side) and then made that zone's thermo call for heat. Once the return side came back hot, I shut off those valves and moved on to the next zone. On the first 2 baseboard zones, I could actually hear the spirovent piss out a bit of air (good!). I did the 3 baseboard zones one by one, then did the hot water zone, then did the radiant zone last because I knew it'd take the longest.
It came back hot and so we set the t-stats to their normal (about 120 on the hot water tank and 60 on the wall t-stats, but 70 on the t-stat for the radiant zone because I wanted to make sure that got up to warm). The issue I'm having is that the radiant zone today, tho calling for heat, doesn't seem to be getting warm in the bathroom itself. On the return line for that zone, it comes back and branches, one side goes to the return side of the boiler (not feeling warm there like it did when we first started it up), and then the other side branches into a mixing valve on the circ pump side which does feel reasonably warm. The gauge in the pipe just above the circ pump is reading 150 (I think the boiler max is set to 200). We have had an issue before in bitter cold where if the primary keeps calling for heat, the radiant just doesn't get to keep up. For that reason, I turned down the t-stats to 55 to see what happens but..........
(And I apologize for the long post but I wanted to give as many details as possible)
Couple questions: Should I adjust the mixing valve to take the temp going to that zone up a bit (say 180)? Is it possible that maybe there is an airlock in the radiant floor zone even tho there wasn't before and the spirovent isn't handling it? It just seems weird that not 5' from the return's drain spigot, it's warm and warm over to the mixing valve UNLESS (and I don't remember if hot goes to cold or vice versa, it's feeling warm up in there because the boiler water is pushing up and not that it's really warm from the return water). I did NOT check the pressure in the expansion tank and maybe I should. I feel like we've had similar issues before and tho there doesn't appear to be an air leak, it needed a few pounds. maybe the radiant zone just needs more help? I was thinking maybe that zone needs a bigger circ pump but the house was built 16 years ago and except for a few incidents, it's always been fine so I'm guessing not.
Thanks in advance for any insite you can offer.
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