Blazedog
New Member
hello,
I have been lurking here for a long time as a nonmember and I'd like to say upfront how much useful information I have found and have seen you share with others. Thanks for helping the plumbing industry.
So, we bought this house a few years ago and it had a radiant floor heat system installed in the kitchen. We turned it on and heard the pump humming so we knew it powered up but never used it. This year we have the need to use it and I have some questions about it.
I'd also like to say that the contractors who built this addition to the house for the previous owner did a lot of questionable things so im not even sure if everything was done that should have been on this system. From what I've read there should be floor sensors. As far as I know there are none.
So heres the setup: 30 gallon electric hot water heater. Outlet has a pressure and temp gauge right above the tank. A few inches later is the water pump. An aquastat is on the pipe that cuts the signal from the thermostat to turn off the relay which turns off the pump. Then it goes to a 2 zone manifold and plastic lines go into the cement/tile slab. Returns cone back to another manifold with an auto air bleeder and then back into the tank.
So if I set the tank temp higher than A then the pressure in the system climbs to about 50 psi. It seems high so I lowered the temp back to A. The aquastat settings are a mystery because someone messed with it before me and I don't know what they started on. It's a Honeywell L6006C aquastat. The differential wheel doesn't seem to do anything. I've set the limit at about 125 with a differential of 10 and assume that means hot water pumps to 125 and then shuts off until it drops to 115. I'm also assuming the off time is to allow the water heater to make more hot water. Is that what the aquastst is supposed to do?
If I set it lower than 125 the pressure stays lower but im seeing the floor return water temp rising until it levels off at about 80 and then the water in the tank can't seem to keep up with the temp loss so the pump keeps running until the return water temp starts to drop and never satisfies itself. Am I just not waiting long enough for the temp to stabilize? Ive waited about 1-2 hours.
So I've thought about movingbor adding an aqua stat to the return and having it shut the pump off when the temp gets too hot. Is that a reasonable thought of a way to control the water temp?
There also is an expansion tank before the supply manifold. There is air in it but I haven't set or checked the pressure. Just to mention the water in the system was cloudy and probably never flushed so I completely flushed it until it all ran clean. I even drained the tank and with the two bleeders on top and the auto sir purge upen I refilled it with wTer until all the Air came out. Pump runs pretty quiet and I don't see bubbles pass through the lines as I did before I flushed it. I also filled it up about 12 psi. What is recommended fill pressure cold and for the expansion tank?
I know it's ally but I'm trying to eliminate as mAny return questions as possible to help solve.
Thanks,
Nick
I have been lurking here for a long time as a nonmember and I'd like to say upfront how much useful information I have found and have seen you share with others. Thanks for helping the plumbing industry.
So, we bought this house a few years ago and it had a radiant floor heat system installed in the kitchen. We turned it on and heard the pump humming so we knew it powered up but never used it. This year we have the need to use it and I have some questions about it.
I'd also like to say that the contractors who built this addition to the house for the previous owner did a lot of questionable things so im not even sure if everything was done that should have been on this system. From what I've read there should be floor sensors. As far as I know there are none.
So heres the setup: 30 gallon electric hot water heater. Outlet has a pressure and temp gauge right above the tank. A few inches later is the water pump. An aquastat is on the pipe that cuts the signal from the thermostat to turn off the relay which turns off the pump. Then it goes to a 2 zone manifold and plastic lines go into the cement/tile slab. Returns cone back to another manifold with an auto air bleeder and then back into the tank.
So if I set the tank temp higher than A then the pressure in the system climbs to about 50 psi. It seems high so I lowered the temp back to A. The aquastat settings are a mystery because someone messed with it before me and I don't know what they started on. It's a Honeywell L6006C aquastat. The differential wheel doesn't seem to do anything. I've set the limit at about 125 with a differential of 10 and assume that means hot water pumps to 125 and then shuts off until it drops to 115. I'm also assuming the off time is to allow the water heater to make more hot water. Is that what the aquastst is supposed to do?
If I set it lower than 125 the pressure stays lower but im seeing the floor return water temp rising until it levels off at about 80 and then the water in the tank can't seem to keep up with the temp loss so the pump keeps running until the return water temp starts to drop and never satisfies itself. Am I just not waiting long enough for the temp to stabilize? Ive waited about 1-2 hours.
So I've thought about movingbor adding an aqua stat to the return and having it shut the pump off when the temp gets too hot. Is that a reasonable thought of a way to control the water temp?
There also is an expansion tank before the supply manifold. There is air in it but I haven't set or checked the pressure. Just to mention the water in the system was cloudy and probably never flushed so I completely flushed it until it all ran clean. I even drained the tank and with the two bleeders on top and the auto sir purge upen I refilled it with wTer until all the Air came out. Pump runs pretty quiet and I don't see bubbles pass through the lines as I did before I flushed it. I also filled it up about 12 psi. What is recommended fill pressure cold and for the expansion tank?
I know it's ally but I'm trying to eliminate as mAny return questions as possible to help solve.
Thanks,
Nick
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