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[trz]

my water to water plate exchanger doesn't seem to be working very consistantly.   sometimes i have hot water and sometimes it's only luke warm regardless of how the fire is burning. What's up with that?

[Scott7m]

Where did you install it?  Did you splice into the cold supply line entering the hot water tank!?

How big is the plate exchanger?  How many plates

[trz]

it's all installed correctly .   this is my fourth season on the furnace. just started acting up!

[Scott7m]

If it's installed correctly it would or should be hard to notice any dips in temperature as the hot water tank would act as a buffer.   If the water temperature is 170 in the stove it shouldn't vary....

But without knowing the size, plates, brand of stove ect then it's much harder to diagnose the problem

[willieG]

it's all installed correctly .   this is my fourth season on the furnace. just started acting up!

is this system on a header or all 'appliances" in series?

[trz]

i'll try and get that info tomorrow eve.

[husky 555]

First season with modified shaver 250.  My ranco reads 172 degrees and the inside furnace temp gauge reads 152 and my house seems to be taking an abnormally long time to heat.  I guess it is possible but hard to imagine losing 20 degrees in a 70 foot run with my lines buried 40 inches.  My lines are also insulated but I believe my schedule 40 conduit has a crack in it somewhere.  I am also wondering if my heat exchanger could be causing the problem.  Any thoughts. 

Last season I did not have an accurate aqua stat to tell me the owb temp.  only that my inside furnace consistently read b/w 160 and 170 degrees and the house heated up rather quickly.  Other than the obvious, is there that much difference b/w 160 and 152 degrees when heating a house.

I also need to get a hold of a thermal gun

[willieG]

it is entirely possabe that your aquastat is reading wrong.

as for water temps i have read that in single tube fin baseboard rads that 180 degre water can deliver 650 btu per foot of rad while the same rad at 140 degree water would only give off 350 btu

as for heating your home with lower temps water, it is obvious that the btu's  in any type of appliance would drop. the trick is to deliver more btu to the room than you are losing. for example if yoru room was losing 5000 btu per hour and you were delivering 50,000 your room would heat up quite quickly. on the other hand if your room were losing 5000 btu per hour and you were only delivering 30,000 btu, you would still be able to heat your room but the rise to your set point would take much longer as the ratio of heat loss to delivered btu is clsoer. think of it as a 4 gallon bucket with a hole in it..lets say the bucket is losing 1 gpm out the hole. if you deliver to the bucket 2 gpm and you are losing 1 you would fill the bucket eventually but very slowly ( about 5 minutes)if you were to deliver 5 gpm you would it would only take about 1 min (even if my math is wrong you should get the picture)

right now my dry well aquastat says my shut of point is 160 off and 145 on, my thermometer i have installed in the water jacket reads the aquastat shut off as 170 and when the aquastat kicks in at it's 145 setting my thermometer reads 155

[Scott7m]

If it's a sudden problem and then you suddenly notice home isn't heating as well, it's very likely youve took water on in the piped

My cousin did his lines like yours, nearly the same difference run, and he loses 20 degrees too

[husky 555]

I started my furnace this past Sunday before Hurricane Sandy came.  A day later the  power went out.   It is entirely possible that my line took water as it has been very dry as of late and Sandy dumped about 3 inches of rain in a short period of time.

On the other hand  It may not be a sudden problem just the difference with the modified furnace that i am running this season.

Last season I had a strap on aqua stat (on supply line) that I don't believe was very accurate.  For all i know my owb temp could have been running at 190 all season.   This season I put a dry well in with the ranco digital.

I like the idea of running the furnace at 160 and most of my friends in the area run their furnace at 160.  The more i read on this forum it is better to run at 180.  I've been running this season at 170 but may have to increase to 180.  Trial and error sucks but  learning is not a bad thing either.

I will also look for a thermal gun then I should be able to see how much temp I am losing by checking the supply and return lines at the back of the furnace.

Thanks to yours and willieG's post.  They have been most helpful.

[Scott7m]

Yep, check it out and see what you find

Glad we can help

[trz]

I do believe my thread has been 'hijacked'   lol

[husky 555]

Sorry trz.  I thought this was the best thread to post on with my issues. 

Anyhow, I switched back to the inside furnace and cranked house temp up to 74 degrees.   At 6:40 this evening the actual temp in house was 70 degrees and now at 7:18 the temp is 71.  Something is not right.  I'm thinking that my taco pump on the inside furnace is pooping out or somehow air got in the inside system.  Not really sure at this point what is going on.

I purchased an infared gun and had some fun with it.  Not losing as much underground temp as I thought.  Temp. at owb 164 temp right when it comes inside 161.  I also measured at supply line to baseboard heater it read 175 and the return back to inside furnace read 168. 

Any additional thoughts out there would be nice.

[willieG]

Sorry trz.  I thought this was the best thread to post on with my issues. 

Anyhow, I switched back to the inside furnace and cranked house temp up to 74 degrees.   At 6:40 this evening the actual temp in house was 70 degrees and now at 7:18 the temp is 71.  Something is not right.  I'm thinking that my taco pump on the inside furnace is pooping out or somehow air got in the inside system.  Not really sure at this point what is going on.

I purchased an infared gun and had some fun with it.  Not losing as much underground temp as I thought.  Temp. at owb 164 temp right when it comes inside 161. 

I also measured at supply line to baseboard heater it read 175 and the return back to inside furnace read 168. 
if the line above is true, taht would lead me to believe your indoor water is moving fast enough as the delta of 7 degrees is very good. (unless)  you should feel all your baseboards while the room is calling for heat, if you finda luke warm or cool one then you likely have some sort of air lock in it. if teh home heated properly last year and this year it does not (even using only the original indoor system) then either the coons ripped all the insulation out of your house or you are not using all your  base board heters ( i am assuming you use 100 percent baseboards?)
Any additional thoughts out there would be nice.

[trz]

what kind of ir gun did you buy.  i bought a cheap one (30.00) at home depot and couldn't get consistant readings.