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Discussion Starter · #1 · (Edited)
Hello. I'm looking for experience or ideas to guide me in troubleshooting my hot water baseboard system. I have a WM Ultra boiler with Taco 007 pumps. I have a domestic hot water loop with a 007 IFC (no issues). The main heat loop has a "close coupled tee" loop with a 007 IFC, and the house circulator is a regular 007 that splits into two zones (with zone valves). Everything runs and works fine, except when the call-for-heat stops, the system makes a 1 or 2 second rumble as the pumps stop.

All I can think of at the moment is that the IFC is making noise. My first thought is to remove the IFC pump in my heat loop and pull the check valve out of it. I could also swap the IFC pump in the heat loop with the IFC pump in the DHW loop.

Any ideas?
 

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Could be zone valve is closing to fast causing water hammer simmilar to domestic piping. Try leaving one of the zone valves open and turning the system off to see what hapens.
 

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If you are using zone valves you do not want IFC on the pumps. Yank it out. You only use IFC's where it will be the way of checking flow when not required.
 

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Discussion Starter · #5 ·
If you are using zone valves you do not want IFC on the pumps. Yank it out. You only use IFC's where it will be the way of checking flow when not required.
I think I need the check valves to make my DHW loop work right. WIthout the check valve, the pump for the DHW loop will tend to send flow around my primary loop instead of through the boiler. Sound right?
 

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BIGRED
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Reread tk03's response. What he said is correct. You don't need the chk valve in the zoned loops. Leave the waterheater loop alone because you are right; you do need the chk in that loop or install a flo-check in the heater loop.
 

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Reread tk03's response. What he said is correct. You don't need the chk valve in the zoned loops. Leave the waterheater loop alone because you are right; you do need the chk in that loop or install a flo-check in the heater loop.
That will depend. On where the zone valves are installed.
If installed on the return. You can get a gravity heat in the heating zones when the Domestic is being heater.
 

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Discussion Starter · #8 ·
Reread tk03's response. What he said is correct. You don't need the chk valve in the zoned loops. Leave the waterheater loop alone because you are right; you do need the chk in that loop or install a flo-check in the heater loop.
The zone valves only stop flow through the secondary loop. I would only get a little flow though the boiler without a check valve in my primary loop.
 

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Discussion Starter · #9 ·
That will depend. On where the zone valves are installed.
If installed on the return. You can get a gravity heat in the heating zones when the Domestic is being heater.
Zone valves are on the returns.

I'm more worried about making the domestic loop actually pump through the boiler. THe flow check is required to prevent the DHW loop from just flowing around my closely spaced tees and not going through the boiler.
 

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BIGRED
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Addicted There is no reason to have flo-chek on any secondary with a zone valve on the feed or return side of the loops. That covers ZONE VALVES. They isolate your loops so there will be no thermal travel. On a DHW secondary without a zone valve you DO need a check valve or flo-chek so that the heater only gets reheated on demand from the aquastat. You would wind up with 180 F water coming out your faucets otherwise. Your primary loop, from your boiler to your boiler array doesn't really need a flo-chek in it, but if you have one already in the loop it's OK. I'm not sure if you have injection flow control between your primary and secondary or not, but WM used to push it as the end all for system control. If this is what you are referring to take a look for a 1/2" valve (manual) on your bypass loop or return from your secondary to your primary. It maybe partially closed and causing cavatation momentarily when the pumps shut down. Pumps get old and loose like me and tend to do funny things with age. Open it up abit and retry it.
 

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Discussion Starter · #11 ·
Addicted There is no reason to have flo-chek on any secondary with a zone valve on the feed or return side of the loops. That covers ZONE VALVES. They isolate your loops so there will be no thermal travel. On a DHW secondary without a zone valve you DO need a check valve or flo-chek so that the heater only gets reheated on demand from the aquastat. You would wind up with 180 F water coming out your faucets otherwise. Your primary loop, from your boiler to your boiler array doesn't really need a flo-chek in it, but if you have one already in the loop it's OK. I'm not sure if you have injection flow control between your primary and secondary or not, but WM used to push it as the end all for system control. If this is what you are referring to take a look for a 1/2" valve (manual) on your bypass loop or return from your secondary to your primary. It maybe partially closed and causing cavatation momentarily when the pumps shut down. Pumps get old and loose like me and tend to do funny things with age. Open it up abit and retry it.
I agree about the zone valves, and I don't have any flow checks on my secondary loops.

Here's where I'm stuck:
My primary pump doesn't run when the DHW pump runs. Why would the flow go through the boiler if it can just as easily scoot backwards around the primary loop? I want good flowrate through the boiler. As I understand it, that's the whole point of having a primary and secondary loop in the first place. Maybe my assumption that the flow will easily scoot backwards through a non-running pump is incorrect.

I think a check valve is needed to force the DHW loop to flow through the boiler rather than going backwards around the primary loop and starving the boiler flow.

Weil McLain install manual shows the addition of a check valve in primary loop when you add DHW.

I'm not certain about injection flow control, but there is no valving between my closely spaced tees. I assume that's the bypass loop?
 

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Discussion Starter · #12 ·
By the way, I appreciate the input. I enjoy being able to discuss intelligently with people who understand this stuff.
 

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Zone valves on the return, without a flow check in the supply. Allow gravity heat.

The hot water runs along the top of the pipe, And the cold water runs along the bottom of the pipe.

Usually its not enough to heat the entire loop. But its more then enough to heat/over heat one or 2 rooms.
 

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Discussion Starter · #15 ·
Zone valves on the return, without a flow check in the supply. Allow gravity heat.

The hot water runs along the top of the pipe, And the cold water runs along the bottom of the pipe.

Usually its not enough to heat the entire loop. But its more then enough to heat/over heat one or 2 rooms.
You are missing the fact that I have a DHW loop in parallel.
 

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You are missing the fact that I have a DHW loop in parallel.
No I'm not. :)

But, I am still waitng for you to post a pic, or drawing of your piping.
 

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BIGRED
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Do you have a single 1 1/4 pipe that can be traced thru one pump from the output of the boiler to the inlet of the boiler? If you do, that is your primary loop. The primary loop is to keep the boiler as near the set operating temperature as possible, period. It is protection for the boiler, against thermal shock only. Secondary loops or system loops or dhw loops or snow-melt loops or any other loops are supposed to be tied to the primary loop to 1. Supply hot water to a given heating circuit and
2. Return the water with the depleted BTU's to the boiler for reheating. Generally several heating circuits or zones can relie on one pump in either the feed or return of a secondary loop to push or pull the heated water around the circuits in the SECONDARY LOOP for those circuits only. If you look carefully you will see that the primary is a complete unbroken loop from the boiler to the boiler. The secondary should also be a complete loop from where it comes off the primary, thru pump(s), zone valve(s), ball valves, flo-cheks, radiators, in floor radiant, sno-melt, etc., all the way back to where it ties into the primary. The DHW is just another secondary, but in this case rather than put an expensive zone valve in the loop people will put either a bigger pump with a chk valve built into it or a pump w/o a chk valve and put in a flo-chek instead. This is so that your sidearm water heater will get hot fast, have faster recovery, and during shut down there is much less chance of the hotter water bleeding off into cooler areas of the system. When your DHW calls for heat, the boiler/primary pump starts up to make sure the boiler gets hot + stays hot. This pump WILL NOT push water around ANY secondary loop whether it be DHW or Heating zones. When the DHW starts up the DHW pump starts up and pushes water around the DHW loop ONLY. If it did not start your winky would get real cold in the shower. The same process happens with the heat zones except that the appropriate zone valve opens first, then the Heat/secondary pump starts up, then the boiler/primary pump starts up, and after a short time delay the ignitor circuit lights off the boiler and you are in business.
 

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Primary secondary piping doesn't protect boilers from thermal shock.
Thats an old wives tale.

The only way it could protect a boiler from thermal shock is if the primary loop moves more water then all the secondary loops combined.

Primary secondary only guarranties that the primary loop moves the amount of water that the boiler needs.

Check out heatinghelp.com

Its a wethead site.
 

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BIGRED
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sounds like someone got kicked out of bed to early this a.m., but I could be wrong. As far as protect or not on boilers and their primary loops you might be right, but not in this lifetime. All the boiler manufacturers I have dealt with (about 12) have all told me the same thing and I have seen it first hand when someone chooses to disregard their warnings. Replacing boiler sections is NO FUN!
 

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Boiler manufacturers, have changed their stories more then one time (the reps at least).

Yes, their latest kick for the last 10 to 20 years is P/S piping cures all..

It doesn't.

A lot of 50 year and older boilers around without P/S piping.

I'm up at 4:30 every morning.
 
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