"vinegar flush" for tank water heater?

[TheGadfly]

Does anyone advise attempting to remove calcium deposits from a water heater using vinegar?

I'm planning to flush my gas water heater and replace the anode rod and I'm expecting to see A LOT of calcified junk at the bottom. My house has hard water, which routinely clogs up my appliances, and I'm pretty sure the water heater hasn't had a flush since it was installed in 2013 (I bought the house last year).

I'm wondering whether pouring 3 gallons of vinegar into the drained water heater will give the appliance longevity. Searching on the internet, I don't see this is a common practice. I also don't see anyone saying NOT to do it. Any insights?

[lthenderson]

I would be surprised if it did anything at all. Most of the deposited crud at the bottom of the water heater is loose sediment that is heavier than water. Simply opening up the valve and draining water out the bottom does little but create a narrow funnel above the spigot entrance through all the layers of sediment.  The most effective way to flush a water heater is to remove the sacrificial anode and using a garden spray nozzle, spray around the insides stirring up the sediment before flushing. Unless you remove it annually, it is probably already seized in place so the next most effective method is to open and close the water supply to the water heater as it is draining and using the incoming pressure changes to stir up the sediment.

[Enough]

I would be surprised if it did anything at all. Most of the deposited crud at the bottom of the water heater is loose sediment that is heavier than water. Simply opening up the valve and draining water out the bottom does little but create a narrow funnel above the spigot entrance through all the layers of sediment.  The most effective way to flush a water heater is to remove the sacrificial anode and using a garden spray nozzle, spray around the insides stirring up the sediment before flushing. Unless you remove it annually, it is probably already seized in place so the next most effective method is to open and close the water supply to the water heater as it is draining and using the incoming pressure changes to stir up the sediment.

Ditto on the water flushing, but I'll add that most hot water heaters are designed to remove sediment by simply flushing with the inlet water and drain.  I have never had to manually spray down the inside.  I live in an area with notoriously hard water and have hot water heater flushes on the maintenance list for my rentals every 3 years.

[Ripple4]

This vinegar idea is well documented, a quick search had several hits. one of the sites indicated filling in the empty tank with water after the vinegar is added through the anode bung, which i assume will reduce the acidity quite a bit from full strength. other instructions do not suggest diluting the vinegar. some instructions say waiting 12 hours, some 6 hours. any idea what the sweet spot is on this?

I've got a electric hot water tank at one of my properties that is on a well, so when i flushed it, there were some chunks. i'm looking at a new aluminum-zinc anode rod, siliphos pellets, ultra fine filtration, and activated carbon to reduce the poor water quality. might be my ignorance talking, but things like softeners and RO, seem like more trouble then they are worth, where large capacity filters/treatments are a once a year thing. This vinegar idea might help undo some of the existing damage. please post an update with how things go.