Taco 5000

Tom DeBrum

Customer has a Weil-Mc sgo gold steamer w/tankless and controlling domestic hot water is a Taco 5000 mounted 7" horizontal from hot outlet from coil, valve unit developed leak at valve stem after approx 2 years,
Aqua stat set @180 and diff. set between 5 & 10 degrees, water level is at 1" below manufactures line on boiler (in bossed on sheet metal) at rest and raises approx
1/4" when running. It seems the valve gets to hot on inlet side. City water, doesn't seem to have any corrosion.
Question is; would you guys heat trap this particular valve like the watts 70A series.

Kal Row

all tstatic mixers need heat traps, to get them to move ...

at least a little, so they dont get jammed in one position from a mineral deposite produced ridgeline

Blackoakbob

heat trap....

Could either of you elaborate on the piping arrangement of of your "heat trap" setup, I may know what it is but I don't follow you.
I probably would not place the mixer so close to the boiler jacket just to stay away from the radiant temp and ambient temp which could effect the operation and longevity of the valve.
Best Regards,

Kal Row

simply a ft up/down unisulated legnth of hot supply pipe...

that causes a convective cool down of even when no water is drawn - and thus a slight movement of the themostatic mixing valve

see http://www.wattsreg.com/pdf/1915328.pdf

clammy

Taco 5000

I've been using taco mixing valves for about a year or so no promblems but as with any mixing or tempring valve a thermal cooling leg is necessary in my mind and if you research you'll find most coil and boiler and valve manbafactors recomemend it so why isn't it done because besides it taking some time you also have to read the direction which seems not to happen to often in the real world .I would have it repiped with 2 unions and tee's for foture ease of the soon coil cleaning to come peace and good luck clammy

Bill Nye_2

Pressure

That is good place to install a relief valve. when the boiler is steaming that coil is seeing about 215°F

Joe Mattiello

A heat trap is not required when using a taco 5000 series mixing valve. It can be installed in any position without any degradation in performance. The thermostatic element ensures the desired mix temperature within the minimum/maximum 85 to 150 degrees range.

Taco, Inc.
Joe Mattiello
Technical Service Technician
joemat@taco-hvac.com
401-942-8000 X 484
www.taco-hvac.com

Kal Row

thanks for the info - good thing you monitor this site....

i would never have known that - i just though the missing heat trap in the diag was for simplicity or oversight, tell your people to revise the pdf to spell that out

this saves so much trouble - many times there just is no room for a heat trap - expect a pickup in sales!