i have two stelrads and stapled up pex between my joists. How can I get more heat?
Slow down the flow and pump speed or increase?
Slow down the flow and pump speed or increase?
Extracting more btu's
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Mike Fromme
Burning Hunk
maple1
Minister of Fire
Slowing the flow will only reduce your return temps - it won't put more heat in the house because, well, the flow is slower, therefore less BTUs per minute are being carried.
And vice versa for raising flow - more BTUs are carried, but the dT will be lower.
So you would need to change up something on your emitters (like the plates mentioned - or insulating underneath) - or raise your supply temps.
And vice versa for raising flow - more BTUs are carried, but the dT will be lower.
So you would need to change up something on your emitters (like the plates mentioned - or insulating underneath) - or raise your supply temps.
Long story, contractor wouldn't do transfer plates because he was worried about damaging the engineered hickory floors.
Flooring manufacturer had no idea how much heat it could withstand. I figure the heat from the sun is hotter on the floor than what heating the joist cavity with 140* water is anyway.
So then I had them install 2-8' stelrads at the west end of the great room (it's 25x35, 20' sidewall and a 12/12 cathedral ceiling. Impossible to heat apparently. Too much cubic feet, Windows and doors.
Part 2, garn is out in my shop, 70' of thermo pex underground.
There's a 20* difference in storage temp vs the temp gauge in my basement panel.
Should I install a larger pump on the circulator at the garn hx, or on the panel in my basement that circulates out to the Garn?
Flooring manufacturer had no idea how much heat it could withstand. I figure the heat from the sun is hotter on the floor than what heating the joist cavity with 140* water is anyway.
So then I had them install 2-8' stelrads at the west end of the great room (it's 25x35, 20' sidewall and a 12/12 cathedral ceiling. Impossible to heat apparently. Too much cubic feet, Windows and doors.
Part 2, garn is out in my shop, 70' of thermo pex underground.
There's a 20* difference in storage temp vs the temp gauge in my basement panel.
Should I install a larger pump on the circulator at the garn hx, or on the panel in my basement that circulates out to the Garn?
stee6043
Minister of Fire
You're losing 20 degrees between your house and the garn? Seems excessive and should probably only be a degree or two at 70'. What's the difference between the return coming from your house vs what's coming into the Garn? Similar 20 degree drop?
maple1
Minister of Fire
Not sure I'll be much more use on this one.
Even then I think more info is needed re. any circulator commendation (temperatures in & out of everywhere and diagram/pictures), for starters. Plus info on sizing emitters to your heat loss (no details on your pex layout/flows/etc.) - was a heat loss calc done on the area?
Basics: Have you measured your actual floor temps? Is there insulation under the pex? If not, I don't think a whole lot of heat is making it from the pex up into your floors. Also, plates should also serve to spread the heat out across the floor.
70' of thermopex shouldn't lose 20 degrees - should only be a couple. So sounds like there is other stuff going on too, and can't see your whole system from here - don't know exactly where in the system layout that temp diff is.
Even then I think more info is needed re. any circulator commendation (temperatures in & out of everywhere and diagram/pictures), for starters. Plus info on sizing emitters to your heat loss (no details on your pex layout/flows/etc.) - was a heat loss calc done on the area?
Basics: Have you measured your actual floor temps? Is there insulation under the pex? If not, I don't think a whole lot of heat is making it from the pex up into your floors. Also, plates should also serve to spread the heat out across the floor.
70' of thermopex shouldn't lose 20 degrees - should only be a couple. So sounds like there is other stuff going on too, and can't see your whole system from here - don't know exactly where in the system layout that temp diff is.
hondaracer2oo4
Feeling the Heat
Temp gauges can be off from each other. Can you move the supply gauge from the boiler to in the house to confirm the temp drop is really 20 degrees. What kind of lines do you have?
maple1
Minister of Fire
Hard to tell on the 20° thing, not enough info. There must be a HX in between, and maybe other things. Maybe some uninsulated metal piping too? And 'storage' - does that mean the Garn itself? At the supply outlet or? And exactly where is the panel temp guage?
A good consistent IR temp gun would help here - along with maybe some flat black spray paint for shiny measuring surfaces. A lot of temp info should be gathered....
A good consistent IR temp gun would help here - along with maybe some flat black spray paint for shiny measuring surfaces. A lot of temp info should be gathered....
Garn is now at 150*
top picture, water enters from the boiler at the bottom where the grey thermostat box is.
travels to the HX for a storage tank for DHW in the second picture.
then up to the closely spaced T for my back up propane boiler. (not turned on).
the white thermometer is 130*
the flow then in the 3rd picture is the vertical pipe on the right with the 3/4 pex to my stelrad. the white handle valve regulates flow between the supply and return.
the flow then goes along the cast iron pipe where the round thermometer beside the green control box reads 130*.
the flow for my infloor pex goes supply at the green wilo pump and return temp is 110*, so i have drawn 20*. (7 runs and i think we used all 300' per run) which is picture #4.
the flow no travels, through the grey expansion tank to the green wilo pump on the left (which up to this point has been "pulling". here temp is 120* and then back to picture #1 where it goes back out to the boiler.
The Garn is in an un heated shop. the primary pump is a TACO 007, installed as per Garn recommendations. The pipes at the Garn and HX are not very well insulated, I have batts of Pink wrapped around them. I know this is not ideal but even on mild days the temp difference is still 20* so i dont believe im loosing that much in the shop but i will try to insulate these pipes better.
The 70' of pex to the house is thermo pex, two pipe in and insulated casing buried down 5'
Long winded explanation, but that's about all i know about it.
.Thanks for everyones input
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Mike Fromme
Burning Hunk
Does the first pic show the insulated pexcoming through the foundation, or am I missing something, looks wrapped in a sdr35 pipe. Do you have a pic of the plate hx and piping
Mike Fromme
Burning Hunk
Do you have a way to measure the surface temp of the hard wood floors?
Have you tried adjusting the mixing valve to give higher supply temps to the radiant floor manifold?
It's currently 5* outside and 66* in my great room.
Boiler 185* now, 150* at the panel
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floor temps in room with ceiling 74*, bathroom travertine floor 79*, great room 69-72* depending where it was taken and stelrad 136*
I was told to install a larger pump, should it go at the Garn or in the basement panel?
As you can see there are no shut offs to take the HX off and clean it, however there is no crud in the Y strainer before the pump.
I have tried to change the flow, all I am able to do is slow the flow to the rads which I don't want to do either.
I was told to install a larger pump, should it go at the Garn or in the basement panel?
As you can see there are no shut offs to take the HX off and clean it, however there is no crud in the Y strainer before the pump.
I have tried to change the flow, all I am able to do is slow the flow to the rads which I don't want to do either.
When was the last time you removed the mesh strainer or acid cleaned the hx, either or both could be a contributor
Mike Fromme
Burning Hunk
Potential problems with your heat exchanger or underground piping aside...You have 150* water available in the basement... Which is enough for a properly designed radiant system to work.
Your floor temps are too low to meet the BTU loss of the room.
Two ways to fix that. Transfer plates or higher supply temps at the radiant manifold.
I'd try adjusting the mixing valve so the supply temp is higher and see what effect you have on the floor temps. If you can get the great room wood floors up to ~80* without the tile going over 85* you may have enough BTUs 'extracted' to meet the loss. But it's really just a band aid fix for the hack work your contractor did.
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maple1
Minister of Fire
In & out temps everywhere should help too.
E.g. - in & out of both sides of the HX.
But even if there is an issue there, as Mike says, you should be getting warmer floors with 130-150 supply temps inside. Although a temp rise might help out the Stelrads. So I'm still not seeing where a pump change will help, yet anyway.
E.g. - in & out of both sides of the HX.
But even if there is an issue there, as Mike says, you should be getting warmer floors with 130-150 supply temps inside. Although a temp rise might help out the Stelrads. So I'm still not seeing where a pump change will help, yet anyway.
It's not unusual to lose 10 plus degrees on opposite sides of a heat-exchanger, if it's only losing 5 degrees in the transfer that's doing pretty good.
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Wow , what a great looking timberframe home! All thats missing is a Molsons sitting on the table to watch that hockey game-it could be a Christmas card for men.
stee6043
Minister of Fire
Radiant floor isn't intended to heat the areas above where you'd normally occupy the room. Hence it's potentially outstanding efficiency. It heats the 6'-8' off the floor that you actually use. I don't see anyone levitating at 15' above floor level in your photo so I'm assuming they also aren't complaining about the colder air up there? ha.
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