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# boiler noise

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Member Posts: 190
A customer has a 4 zone gas boiler with 4 Taco 0011-F4. The complaint is " it sounds like it is raining when the heat is on" And it does. I cycled each zone individually, and they all make noises. The heat works ok, but the noise is an issue. These people just moved into the house, so they don't know any history. My first thought is that these pumps are too strong are whipping the water through the lines. How do you figure out what pump would be the correct one if you can't accurately measure all of the piping because it is buried in the walls? Any other ideas on what the noise could be other than that? The boiler pressure was at 15psi, and all of the zones are coming back hot and working. It's just the noise. Ty

• Member Posts: 23,543
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Measure the delta P across the pump, then the pump curve will give you the flow through the system. Then also look at delta T, and see if the figures make any sense.
Br. Jamie, osb
Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
• Member Posts: 190
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what is the easiest way to get the delt p across the pump?
• Member Posts: 4,469
edited November 2017
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Finally, the following formula may be utilized to convert PSID into HEAD [feet]

HEAD [feet] = PSID x 2.31/SPGR, where SPGR = Specific Gravity
PSID= DeltaP or differential pressure
• Member Posts: 23,543
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drhvac said:

what is the easiest way to get the delt p across the pump?

Um... a pair of gauges... one on each side.
Br. Jamie, osb
Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
• Member Posts: 260
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Rain? My wife used that description when there was some air trapped in the lines.
DIY'er ... ripped out a perfectly good forced-air furnace and replaced it with hot water & radiators.
• Member Posts: 185
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You haven't told us the size of the system. But, unless it is very huge, four zones with 0011 pumps each is way too over-pumped. Look at the pump curves. The 0011 curve is way too steep. Try one zone with a 007 and see if that resolves the noise.
• Member Posts: 190
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Jamie hall - I have yet to see a place to attach a gauge on each side of a circulator pump on a residential system, so that's why the question was asked. Thank you Gilmorrie. Its a big house 199,000 btu's, but I agree that the 0011 seems way to big.
• Member Posts: 4,469
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You should be able to form some reasonable assumptions about the length of at least some of the zones...no? Do a heat loss for the ones you can, and try pumping those to the heat loss. Or try a Delta T circ. on one. Or , drain one and put gauge ports on either side of a circ.
• Member Posts: 11,089
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I am with Boon, I get the rain sound in BB htrs when they need air bled out. FWIW