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Re: Unico potable water furnace, expansion tank pressure
Hi, A couple of thoughts. Try putting a gauge on the drain valves of the tanks and measure the actual pressure. That might help in getting to the truth a bit faster… I would want a drain and waste valve installed between the expansion tank and system, so you can check/charge it easily… The pump is mounted vertically in a way that can trap air and damage the bearings. I'd rotate it to sideways… The pump is pulling water away from an air vent. If pressure falls low enough, it could pull air in and cause problems… The older tank is nearly ten years old. It needs a new anode! Also, it's time now to check the anode on the newer tank.
Yours, Larry
Re: Unico potable water furnace, expansion tank pressure
Hold on. You’re missing something here!
The pressure in the tank is supposed to be set to match the minimum pressure in the system. In other words, the system pressure determines the tank pressure, not vice versa. Therefore, there’s no fixed (one size fits all) pressure setting.
It makes no sense to set it at 15 psi if the minimum pressure is 60 psi or more. That would greatly reduce the acceptance volume of the tank and render it virtually useless.
It would appear from your description of flushing minerals out of the tank annually that potable water is also being heated by the water heater. Correct? That’s unfortunate because you run the risk of Legionella contamination in the heater from stagnant water from the heating system. However, there are a lot of these types systems out there from days gone by.
At any rate, you need to find the static water pressure on the water heater and set the air pressure on the expansion tank to the same. That must be done with no water pressure on the expansion tank.
Your circulator is also mounted incorrectly. It needs to be rotated to where the motor is horizontal, not vertical.
Ironman
Re: Unico potable water furnace, expansion tank pressure
If this is correct — that is, if that valve is just a backflow preventor and not a pressure reducing valve, then the pressure tank needs to be set to the domestic water pressure when the system is cold, and the pressure tank needs to be certified to operate at that pressure.
Re: My SteamPunk boiler
Yeah, I would start saving………….and I would save fast! I don't know if you're going to install the new one yourself or not but if it was me, I would size the new boiler and have it in the basement on standby.
But I commend your ingenuity you did a neat job. Just doubt it will last.
Re: My SteamPunk boiler
The boiler itself isn't all that expensive, for that amount of work you could have replaced it.
mattmia2
Re: WM CGa control board
High failure items on control boards are, solder joints, relays and capacitors. If you (or a friend) can deal with those items it can be an inexpensive repair.
For most industrial electronic repair companies the hourly rate makes it not economical to repair circuit boards that can be (rather) inexpensively replaced.
There are places that seem more focused (and probably others out there)
https://www.upfix.com
http://hvac-circuit-board-repair.com
That appear to do that type of work, I have never dealt with them.
IMO (I'm not a Lawyer, but have done a tiny bit of research) where the liability issue mostly comes in is when someone modifies the circuit board away from the manufactures original intent. Simply correctly repairing age related or use related defects, is not a big deal.
The pipe is leaking, the plumber replaced it.
The capacitor is defective the electronics tech replaced it.
Not the big drama some folks seem to want it to be.
109A_5
Re: Domestic hot water
I might check the check. as @Kaos mentioned. when you started to heat for the first time this season the check valve may have not completely closed on the space heat side of the system. An easy to check it is if the proper valves were installed you can shut off a valve to the space heat loop to the AHU and see if the problem goes away.
The following diagram illustrates how the water can flow backwards when the circulator pump is off and the check valve is passing.
When the circulator pump is operating, the reverse flow can't happen so you get HOT water. When the circulator is not operating the reverse flow will allow lower temperature from the AHU coil to mix with the Hot water and you end up with Warm Water
Re: Gorton #2 or Hoffman 75
Hoffman products are very high quality, as are Gorton. The greater air expulsion rate of the Gorton #2, which is in the same price range and close in height, make it the better choice in most cases. Mad Dog
Re: Cost to clean a heat exchanger?
They don't make a more simple boiler. That's an open draft hood, so I hope the tech got the probe up over the top of the block. With those numbers, it seems the techs sampling was diluted. Atmospheric oxygen at sea level is about 21%, so getting 16.58% during a combustion test means the tech didn't stick the probe where it needs to be stuck.
@Evan0307 , did you see for yourself the dirty flue passages in the boiler? Dollars to donuts its clean as a whistle.
HVACNUT