Piping to Power Flush a BoilerMate

NTL1991

I'm getting complaints from my parents about intermittent rusty hot water from their BoilerMate ever since the town replaced the water main on their street (and when they do hydrant flushing). The problem is that their tank is piped in a way which prevents power flushing. The cold water feed tee's into the inlet at the bottom of the tank with a drain. I've also noticed that this 3/4" x 1/2" x 1/2" reducing tee happens to be black iron.

My plan is to re-pipe the cold water inlet/drain piping in brass, starting with a 3/4" coupler from the BoilerMate, to a reducing tee with a new ball valve drain. Brass x Copper union heading up to the existing 1/2" copper cold water inlet and shutoff ball valve.

To be able to power flush, I'm thinking about this for the hot water outlet:

Leaving the factory tee on the top of the BoilerMate, T&P valve at the top, brass nipple off the side into a second 3/4" tee. 3/4" ball valve drain off the bull of the tee. Brass x Copper union. Existing 1/2" copper has no heat trap. Thinking about a 1/2" long turn elbow down and a return bend up to existing ball valve.

If I close both the inlet and outlet ball valves, I connect a garden hose from the new drain at the top to the washing machine hookup to pressurize the tank, and power flush the sediment out the drain.

How would you guys pipe it to allow for power flushing?

hot_rod

A couple valves like this topped bottom. You want to be sure and isolate the piping so as to not flush the crud into the system.

something like a 1/2 hp transfer pump would stir things up inside.

EBEBRATT-Ed

By all means get rid of that black tee before it lets go and causes a flood. That could be the reason for your rust as well

NTL1991

Thanks. I'll be doing this work this weekend. I have a pretty good collection of brass fittings already, so I only need to pick up a couple. Wish I had a couple of those ball valves laying around, they look perfect.

I'll try to get a picture of the before and after

Big Ed_4

Add an hose spigot above the cold water shut off ... Shut off and pump down the tank ... Make an rinser ...3/8" copper tubing to slide down though the top 3/4" hot water supply tap and inside of the internal coil .. Slight bend and crimp at the end of the copper tubing .. Rig the 3/8" with fittings to connect to an washer machine hose , connect to the new spigot to supply water, turn on the sprayer to rinse off the coil , run the pump to remove the mud .. You will need to move the rinser up and down and around spraying the inside of the coil outward ...

NTL1991

That's a good tip. I'm not too sure how bad the coil is, I'm pretty sure this is a town water supply issue, but cleaning the coil can't hurt.

I heard about draining the tank, bumping the boiler water up to 200-210, opening the zone and shocking the coil with cold water to help loosen deposits. This wand trick could be used to do the same thing.

Thanks

hot_rod

I'd take Big Ed suggestion and go one step more.

You can get these kits at most all plumbing suppliers and many box stores. it includes all the stuff you need to flush and de-lime the tank. There are dozens of brands, this happens to be a RectorSeal.

I'm 99% sure you have some limescale, and hard water deposits inside the tank and on the HX coils, these kits do a great job getting you back to like new conditions.

You will find other uses for the pump also.

NTL1991

Cool, I'll take a look and see. Deposits on the finned coil means longer run time for the boiler. I've gotta drain everything anyway, I might as well delime it at the same time.

Amtrol suggests ice machine cleaner, I believe?

hot_rod

All the kits come with a mild acid, citrus acid , I believe.

Here is an example of how I use the kits to de-lime 3 way valves. These small valves only take about 15 minutes to clean. Unless they are plugged solid.

Like Ed suggested put a nozzle of some sort on the hose to get more spray on the finned coils.

Carwash or pressure washer nozzles work well and can adapt to a hose to push inside the connections.