Sales Associate - Taco 595 thermostatic bypass valve

TimK

Anyone have any suggestions on repiping or replacing a Taco 595 thermostatic bypass valve?

icesailor

What do you need to know?

What's the problem? Why do you need to re-pipe it and what is the current valve doing now?

TimK

Taco 595

Element is sticking

icesailor

Sticking:

A quick romp around the Web finds that that valve may not be made anymore and was problematic. There are better ways to do what you are probably doing,



Are you using it to control potable hot water or using it as a hot water extender?

Take the cartridge out and soak it in white vinegar. Then, carefully clean the scuz out of the barrel where the cartridge slides.

Or replace the valve.

TimK

Taco 595

The valve is used as a hot water boiler bypass with a thermostatic element that begins to open at 150 and is open fully at 180, diverting hot water directly into return and ensuring some degree of protection from thermal shock.  I can see how it can be re-piped with ball valves and or 3 way diverting/mixing valve.  I wanted to stay away from temperature modulating valves.  I just did not know if someone had more experience with these devices.

icesailor

Mixing/Low temp Water:

I don't know what you are trying to do but if it is an oil boiler, 140 minimum boiler temp will stop condensation. If gas, 120 or higher.

I put a Taco "I" series 4-way mixer on a system. You won't get any shock with that and the valve controls all the operations itself. And you can use outdoor re-set and still protect the boiler from thermal shock.

What is so unusual about this system that thermal shock is an issue?

Joe Mattiello

595-1 by-pass valve

I did some research on the replacement thermostatic assembly we offered for this valve. We stopped offering the element back in 2005.  For your reference I attached a piping schematic showing the 595 installed as a by-pass.  The objective was to keep the boiler hot minimizing thermal shock, and condensate.  It was originally engineered for Burnham Boilers back in 1982. The Element, procured from The Dole Valve co, of Illinois part number BN-28235-1 was a purchased item we used in our 595-1 valve.  

To facilitate the piping I suggest pulling out the element throwing it away, and put the cap back on.  Install a ball valve, or gate valve in the by-pass line running from the return line back into the boiler.  You can throttle the flow using the throttling valve to redirect some hotter water back into the boiler.  It will obviously be a manual flow control, as opposed to the thermostatically control flow.  Hopefully this helps.  If you have additional questions or concerns give me a call. 

Erin Holohan Haskell

@Joe Mattiello do you still have these PDFs? Thanks!

Dave H_2

@Erin Holohan Haskell I have them still, here you go.

Enjoy

Erin Holohan Haskell

Thanks, @Dave H!

jamesloase

Thank you both very much for your help!!

Dave H_2

@jamesloase Are you replacing or do you have one installed?

I ask for two reasons, one to help - please don't hesitate to contact me and
Reason 2, if it is coming out, please let me know. I am trying to build my own "museum" at the training room at Taco and I don't have one of those.

Thanks and Enjoy

Dave H.

dbsoccer

TimK started this thread 10 years ago. I found the thread when trying to solve the same problem he had. I discovered, with the help of an industry expert, who works for probably a competitor, that Danfoss makes a thermic bypass valve that looks like it could easily be adapted to replace the 595.

https://www.supplyhouse.com/Danfoss-193B1701-ESBE-Series-1-1-4-3-Way-Thermic-Valve-Body-Only?gclid=EAIaIQobChMIruWBue3w7gIV0FPVCh22swjWEAQYASABEgL6EvD_BwE

bucksnort

If i wasn't going to junk my boiler with this valve I would pop it open and inspect the valve . hopefully I can get thru the heating season without it locking up on me. Mine must be sticking as I get a sudden surge of hot water and then a few minutes cool water and it repeats. No use ripping into it now as no parts are available anyways to fix it. There is no mention of servicing this in my boiler manual.