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Frequently Asked Questions



Taco technical services specialists answer thousands of questions a year. Here we've collected some of the most frequently asked questions and their responses. Browse by product category to narrow your search. Then click on a question to reveal the answer. You can print the FAQ for future reference, if needed. If you can't find an answer to your question here, please contact Taco Technical Support

Matching Frequently Asked Questions
Q:
I have an old Taco PANELTROL valve in my radiant heating system. Does Taco still make this product and are there any replacement parts for it?
Q:
3350 pressure reducing valve,PRV cartridge a replaceable part? what is the part number?
Q:
Applications?
Q:
Are taco heat motor zonevalves suitable for use outdoors?
Q:
Are Taco pumps self priming, or does Taco make a self-priming pump?
Q:
Are the Cast iron and bronze and Stainless 00 circulators furnished with Norel impellers?
Q:
Can a 60 cycle 00" Series circulator run at the lower 50 cycle?
Q:
Can a Taco bladder or diaphragm-style expansion tank be installed in the horizontal position?
Q:
Can I control the Viridian using a DC signal?
Q:
Can I install a 00 circulator outside?
Q:
Can I modulate the speed of the Viridian externally?
Q:
Can I monitor the pump's status externally?
Q:
Can I run the VR25 and VR30 down to 208 Volts?
Q:
Can I use a potentiometer , or rheostat to control the flow rate of a 00 pump?
Q:
Can I use a current robbing thermostat with a Taco zone valve and what does current robbing mean?
Q:
Can I use an external demand to "call" the pump on and off?
Q:
Can I use the alarm contacts from the Viridian to send a speed feedback signal to a DDC controller?
Q:
Can I use the screws of an end switch on a ZVC or SR board to check continuity?
Q:
Can I Wire a WAGS valve to a water heater with an Oil Burner?
Q:
Can I, just a homeowner, install a 00 cartridge myself?
Q:
Can standard pump seals (ethylene propylene, and carbon on ceramic) be used when pumping ethylene or propylene glycol?
Q:
Can Taco 00 series circulators be used to pump fluid other than water?
Q:
Can the 1900 series pump be installed with the motor in a vertical orientation?
Q:
Can the 570-2 series zonevalve be used in an open system, such as domestic water?
Q:
Can the Accu-flo circuit setter be used in a system with cutting oil?
Q:
Can the outdoor reset control PC700 be used with a SR board when used in a primary/secondary piping system?
Q:
Q:
Can the WAGS valve be used on water heaters that are not gas-fired?
Q:
Can use the priority feature on a SR502/503 when used with an SR503/4/6 EXP?
Q:
Can you help select a comparable taco pump to replace my B & G 100 series?
Q:
Can you vary the speed of the Viridian using a 0-10 Volt DC signal?
Q:
Dear Pls send to me the user manual for FloPro program. Regards
Q:
Do I need an Inverter Duty Motor when my pump and motor assembly are controlled by a Variable Speed Drive?
Q:
Do I need the internet to communicate with the Viridian?
Q:
Does the Taco Buffer tank comply with any codes?
Q:
Does the WAGS valve need electricity to work?
Q:
Does the WAGS valve require any regular scheduled service?
Q:
Have multiple zones, each with its own circulator. Why is Hot water passing into zones that are not calling for heat?
Q:
How do I check the air charge pressure in a Captive Air Expansion Tank?
Q:
How do I communicate with the Viridian? (PC Windows 7 version and Mac.)
Q:
How do I force the pump to run at maximum power?
Q:
How do I get my house warmer when using an outdoor reset control?
Q:
How do I know when the WAGS valve has been activated?
Q:
How do I pipe the Taco three way (bypass) zone valve?
Q:
How do I replace the cartridge in my 00 circulator?
Q:
How do I run a system pump on my SR504/506?
Q:
How do I save and report information collected from the data logger?
Q:
how do I size a circulator, or pump for my system?
Q:
How do I wire a 00 series pump?
Q:
How do I wire a Honeywell V8043F Zone Valve to a Taco ZVC control board?
Q:
How do I wire a White Rodgers 1361 Zone Valve to a Taco ZVC control board?
Q:
How do I wire a ZVC404 or ZVC406 so the system pump does NOT run on a DHW priority call?
Q:
How do you clean and de-grease a LoadMatch installation?
Q:
How do you set the 24-hour timer?
Q:
How do you wire a 3 wire thermostat to a SR control board?
Q:
How does the pump measure flow with no external sensors?
Q:
How many protocols can the loadmatch thermostat be used with?
Q:
How should a single pipe hydronic system be installed in a 1200 sq. ft. home with baseboards?
Q:
How to control two Viridians with one control?
Q:
How to fix a Boiler Sensor Error on an RMB or XPB
Q:
How to tell if your 500 series zone valve is good
Q:
I am having a problem maintaining temperature at my zones when my taco zonevalve model 570 is in auto mode. Any suggestions?
Q:
I am looking for an on-line selction program for your plate and frame heat exchangers. Do you have one, and if so can you direct me to it? Thanks!

Q:
I am using a 008-S7 pump in a solar heating system without flanges. What do I cross it to?
Q:
I encounter problems when I try to update my copy of the TacoNet software. What can I do?
Q:
I have a 00 circulating pump that stopped working. It does nothing when plugged in, but gets very hot. Do I have to replace the whole pump or only a part?
Q:
I have a 006-B2 pump that is not working properly. My electric water heater is 2 years old and the water coming out of the outlets is not hot.
Q:
I have a 007 Pump that came with two circular gaskets. I was told to install it with the gasket in the groove of the pump, and to use a second, larger gasket which is in the shape of the flange, on top of it. Is this correct?
Q:
I have a 008-S7 or a 008-V2. Are there replacements for these models?
Q:
I have a 008-V2 pump on my solar system. Do you still make this pump?
Q:
I have a 3-zone residential system with a 219 Flo-Chek on each zone. The manual override thumb screws are all open ~2 turns. Should these be fully closed?
Q:
I have a domestic water recirculation pump that is programmed but I do not get instant hot water
Q:
I have a gas boiler with Taco controls that is short cycling. The problem seems to relate only to the 2nd floor zone. What can be causing this?
Q:
I have a Honeywell L8148E limit control which came with my gas boiler. It has one 24vac zone for a thermostat. I want to implement the SR503 into the circuit, as I have two zone 120vac thermostats. I need to know what the output of the thermostat zones are, along with a n/o contact set I can use for the 24vac zone on the Honeywell. It will be used for a cold start boiler operation with continuous ignition.
Q:
I have a Taco 5000 series mixing valve that I'm experiencing erratic flow at the point of use. what's wrong?
Q:
I have a taco IFS flow switch that is not tripping when the flow travels trough the piping; what's wrong?
Q:
I have an exsisting water heater, and I want to protect it with a wags valve. Can i install the wags valve on my water heater that is already installed?
Q:
I have an old VL2508, what is the current replacement?
Q:
I have installed a sr503-1 with priority in a primary secondary loop and an in direct water heater (priority). In total I have four pumps, one for my primary loop and one for each of three zones. I want my primary pump to come on for 2 zones but not to come on when my indirect water heater calls for heat. Can this be done?

Q:
I made an adjustment to my MPV valve and now it has a steady drip.
Q:
I need a pump for a drain-down solar hot water system. What is the right selection for a 12 foot head?
Q:
I need technical details on how the ZR and ZC terminals interface with the aquastat on a boiler. I wire many boilers and all directions specify cold start or hot start, black box type instructions. I do not fully understand the inner workings, or what happens electrically with either application.
Q:
I need to power my thermostat as there is C,R,W terminals on the Thermostat. How do I get a C connection? I have a SR board.
Q:
I recently installed a Radiant Mixing Block to heat 2 zones of radiant floor. When the block injection pump injects at the 20-40% range, it makes a growling noise that sounds similar to dry bearing. Any suggestions?
Q:
I wanted to compare different pumps to see which one would meet my needs. Couldn't find anything that would show me a side by side comparison. So I moved on. Way to difficult to find anything here.

Q:
I'm a FloPro Team member. When I click on a link to join the Neighborhood, all I get is the log-on screen. I have tried different links, but with the same result. What gives? Thanks Ian - FTS
Q:
I'm having trouble setting up the differential bypass valve model number 3196. Can you help?
Q:
I'm using the 788 differential pressure gauge with the Accu-flo and I'm not able to get a reading.
Q:
I'm using this valve is a well pump application, but the valve is allowing flow through when not calling for heat?
Q:
If a ZC wire from the aquastat is wired to the SR board and the temperature of the boiler is low, will the indicator lights be on, and the circulator be on if there is a call for heat?
Q:
If my RMB is set up in the Delta T mode can I control the temperature to a fixed temperature?
Q:
If the WAGS valve works and shuts off my water supply to the tank will all the water in the tank still leak out?
Q:
Is additional support required when installing the 1600 Series circulators?
Q:
Is it ok for my 00 series pump to run all the time?
Q:
Is the location of the pump important in relation to the expansion tank and boiler?
Q:
Q:
Is the Taco zone valve a three wire zone valve and how do I wire it?
Q:
Q:
Is the WAGS valve harness required with electronic control?
Q:
Is there any power between terminals #2 and #3 of the zone valve operator?
Q:
May I have some information on balancing valve flow corrections for glycol solutions?
Q:
Minimum flow applications (low mass boilers for example).
Q:
My "00" series circulator is running but I am not getting hot water
Q:
My 00 Series Circulator Motor housing is hot to the touch. Is it OK?
Q:
My circulator turns on, but why wont the pump pump any water?
Q:
My home oil burner serves two zones that are zoned using 573-2 and 572-2 zone valves. The 572-2 only works by opening manually. It worked fine for years. How do I check and possibly repair the valve without replacement?
Q:
My inline 1600 series pump has an Emerson motor on it. Is the motor warranteed by Emerson or Taco?
Q:
my system pressure keeps rising and causing the relief valve to spew water out, do I need to replace the pressure reducing valve, PRV?
Q:
My Taco i series valve is not working properly.
Q:
My Taco radiant control does not provide heat. What is Warm Weather Shut Down ( WWSD )and how do I turn on my radiant heat?
Q:
My Taco strap on Aquastat does not turn the pump on and off accurately. Do I have a bad unit?
Q:
My thermostat needs power, and are C, R, and W terminals on the thermostat. Where do I connect the C wire on my ZVC board?
Q:
My water heater is 7 years old. Do I need to buy a new water heater or can I install the WAGS valve on my existing water heater?
Q:
My zone sentry valve has a blinking green light. what's wrong?
Q:
My zone valve power head was removed while it was still hot. Causing the piston in the power head to cool & harded in the open postion. how do I replace the powerhead?
Q:
One of our process pumps will be taken out of service and put away for long-term storage. Any suggestions on proper storage?
Q:
Overload protection - what, how and the effects (auto reset or manual).
Q:
Should I connect a drain to the bottom of my Captive Air Expansion Tank?
Q:
Sizing and "dialing in" to match the required H/Q.
Q:
Taco no longer makes the 568. Are the newer thermostats with no heat anticipators compatible with Taco zone valves? The instructions with the 571 valve say that the thermostat heat anticipator must be set to 0.9A to match the valve. Will the valve function correctly without a heat anticipator in the zone?
Q:
The Zone Sentry actuator has a sticker warning against using this valve on an indirect water heater, and suggests using a tempering valve.
Q:
We are replacing 3hp basemount B&G pumps with Viridian V25s. We will connect as follows: (1) a 3" butterfly valve will neck down to 2.5" then connect to the suction side of the pump. (2) pump will hang (north to south) (3) Discharge will be connected to a 90 deg elbow (4) 2 1/2 inch flowcheck will be horizontal to ground (5) 2 1/2 to 3" transition (6) 90 deg elbow up to flex connector (7) flex connector to 3' butterfly. Is this OK? Anything we should know?
Q:
What are the advantages and disadvantages between the conventional Taco Zone vales and the Taco 00 line of circulators with Integral Flow Check values?
Q:
What are the cartridge part Numbers for the XPB?
Q:
What are the model numbers of the cartridges on the RMB?
Q:
What are the model numbers of the circulators on the RMB?
Q:
What are the motor replacement numbers on the RMB?
Q:
What are the replacement motor numbers for the XPB?
Q:
What are the ZC and ZR terminals on the Switching Relay boards and how are they used?
Q:
What causes my thermostat to short cycle?
Q:
What circulator will replace the old 150, 152, & 195?
Q:
What do the factory defaults (head setting and proportional) and what do they do?
Q:
What does the 007-BF5-J nomenclature mean?
Q:
What effect does ethylene glycol or propylene glycol have on pumps?
Q:
What else do I need to complete the installation other than the valve?
Q:
What flexible coupling should be used on my frame mounted pump when a variable speed drive is controlling the motor?
Q:
What happens if the WAGS valve gets splashed by the PRV valve or when I'm mopping the floor?
Q:
What happens to the performance of pumps when they are piped in parallel or in series?
Q:
What information is required to order a replacement tube bundle for my shell and tube heat exchanger?
Q:
What is a good circulator for an injection pump application?
Q:
What is the best way to pipe a 5000 Mixing Valve when used for radiant heating?
Q:
What is the correct air charge pressure for my Captive Air Expansion Tank?
Q:
What is the current replacement for a CE model pump?
Q:
What is the current replacement for a CM pump?
Q:
What is the current replacement for an FE model pump?
Q:
What is the difference between a 007 Green and a 007 Black?
Q:
What is the difference between a JP and a JM frame motor?
Q:
What is the difference between NPSHA and NPSHR?
Q:
what is the difference between the 555-151rp, and the 555-154rp replacement actuators?
Q:
What is the formula for calculating the pressure differential for a given flow when using the Accu-Flo valve?
Q:
What is the general purpose of Venturi Tees?
Q:
What is the minimum pipe length required on the inlet side of the Accu-Flo valve?
Q:
What is the minimum speed of the motor of a pump controlled by a variable speed drive?
Q:
What is the procedure for plotting the performance curve of a pump if you have an impeller diameter that falls between 2 known diameter impeller cuts?
Q:
What is the proper way to mount my 00 circulator?
Q:
What is the purpose of a tank drainer fitting?
Q:
What is the purpose of the check valve, Taco FLO-CHEK?
Q:
What is the purpose of the Flo-Chek?
Q:
What is the purpose of the screen in the system connection on top of the expansion tank?
Q:
What is the typical application for the loadmatch thermostat?
Q:
What procedure should be followed when purging air from a loop that has an IFC circulator?
Q:
What type of motor should be used with a variable speed drive?
Q:
What type of seal is the CI series pump equipped with.
Q:
When I try to adjust my 5000-2 tempering valve to a low temperature the stem starts leaking.
Q:
When selecting a pump, do I include the head required to get the water to the top of the system?
Q:
when using the WAGS valve, do I need to install a pan?
Q:
Where can I get instructions for diagnostics on a 00 series pump?
Q:
Where is the hydraulic separator installed in the system?
Q:
Why do I need an expansion tank in my chilled water system?
Q:
Why do the relays chatter when a zone calls for heat on a SR502-2 or SR503-2?
Q:
Why do you supply a dam and condensate drain tube with the valve?
Q:
Why does my Flo-Chek leak by?
Q:
Why does my hot water circulate when my Taco pump is off?
Q:
Why does my zone valve let flow through it when it is not powered?
Q:
Why does the seal leak when the pump runs, and stop leaking when the pump stops?
Q:
Why does the voltage read across terminals #1 & #2 vary between 24 & 28 volts?
Q:
Why doesn't my digital timer show a display?
Q:
Why is it that in the Taco controller module the terminal 3 & 4 have to be jumped for 2 wire zone valves?
Q:
why is my check valve taco flow chek making a rattling noise?
Q:
Why is my Flo-Chek or MPV noisy?
Q:
Why is my hot water coming out of the cold water line?
Q:
Why is my RMB making a chattering or growling noise?
Q:
Why is the valve not allowing flow through to the system?
Q:
Why would I need a buffer tank in my hydronic system?
Q:
Will a 006-B4 replace a 006-B4-3?
Q:
Will a 007-F5 replace a 007-F2, F3, F4 circulator?
Q:
Will high humidity environments cause the WAGS valve to trip prematurely?
Q:
Will the Bumble Bee ( HEC-2) run without sensors?