Check the btu going in?? May be underfired or wrong size orfice installed.
If that checked out, storage tank on stand,(eleimating the need for circ pump) piped correctly will do the job.

 

Any of you all deal with commercial washing machines? I have a place that currently runs two machines. One is a 55 pound machine the other is a 60 pound machine. They are using 175° water, with a Bradford White EF 100 gallon 199K BTU water heater.

The issue they are having is after the second load the incoming water temp is down to 120° if they wait about 45 minutes between loads they can get back to the 175° temps that they desire. My question is would a storage tank help the issue? Or is the only solution is to add a second 199K BTU heater? Or is there any other solutions you all might have.

The current heater is only a few months old.

55 & 60 pound machine, that's weight of clothes -- but what's the water consumption per load?
What's the recovery of the W/H?
Is it possible to use waste water to pre-heat the incoming water through an exchanger. Just thinking ... Also 175 degree wash water for clothes what are they trying to sanitize? Are we talking about washing something different?

 

As per my expiriance with a laundry is that they use a lot of water at 150 to 175 in a vary short time depends on the machine so ur best option is to check with the manufacture to get the exact gpm required, and u probably will be good wit another or a bigger storage tank

 

Here are some photo from our last install 399k btu copper boiler and 2 200 gallon storage tanks

 

 

I am still waiting on the make and models of the washing machines. They are washing restaurant linens. I talked to Bradford White and AO Smith they both say the best way to go is a pair of 199K BTU units should more than keep up with the current demand.

They both also informed me that most commercial washing machines uses 2 to 3 GPM for every pound of clothes. The current heater is recovering at 3GPM, so having two heaters it would be able to keep up with the GPM demand of both washers. The facilities that is doing the linen washing was hoping a storage tank would give them enough gallons for each wash with a small pause between loads.

I just wish they asked these questions before the install of their current heater. From the sizing calculators from State/AO Smith site, there should be two of the 199K BTU units, or one 500K BTU unit.

As for gas pressure supply they are running a 2lb system with a regulator at the heater. When I go back there I will double check the WC at the water heater to ensure it is getting enough gas, cause in my eyes, this heater should be able to keep up. According to Bradford Whites sizing calculator the heater should fully recover in 23 minutes.

 

A tankless for a booster heater is out of the question?

 

A big prob I come across with commercial laundry machines is solenoid valves. If it's a big size feed line where possible use a hi temp externally pilot operated solenoid valve like a Cla-val or Watts with a good quality solenoid pilot like an Asco brand. The bigger flow allows quicker filling cycle and Asco's are usually bullet proof. Been caught out in coil warranties too often with the manufacturers rep scratching his head why it has failed within a year or two?

 

Does the system have a recirc pump? I've seen a few times in restaurants, (I know this is a laundry not a restaurant, but same concept), with high volume hot water use, of a fixture or appliance, & a recirc pump, and especially too large of a recirc pump, this is what happens.

1-Large volume of hot water is being used, & large volume of cold water now flowing in bottom of heater.

2-Now the recirc pump is on, & bringing the 180 deg hot water from the end of run, & pushing it back into heater at the bottom, where all the cold water is now coming in.

3- This is now taking excessive 180 deg water, from the end of hot water line, that the appliance is not even using, pumping it back to heater, & mixing it with cold water coming into heater, causing the entire heater to cool down faster, & unable to keep up with demand, &/or recover, causing lower temp of hot water to fixture or appliance.

Solution we did for this particular place was a flow switch on cold supply to heater, so when they were actually using the hot water, the pump would shut off. Just one of my experiences, that kept us puzzled for a bit, & this solution worked, cuz they had no more room, for any more heaters or storage tanks.

 

Solution we did for this particular place was a flow switch on cold supply to heater, so when they were actually using the hot water, the pump would shut off. Just one of my experiences, that kept us puzzled for a bit, & this solution worked, cuz they had no more room, for any more heaters or storage tanks.

Nice post Don, I'll add that to the knowledge bin!
:beer:

 

The project I am currently on, launders something like 80,000 pounds per day. As for the issues you are having, you need to make sure the water heater was sized properly to begin with before you start changing things.

Mark

 

The project I am currently on, launders something like 80,000 pounds per day. As for the issues you are having, you need to make sure the water heater was sized properly to begin with before you start changing things.

Mark

According to BW a 100 gal by 150K BTU heater should handle two 60lb machines. according to AO Smith/State, they need one 100 gal by 300K BTU heater or 2 of the 100 Gal by 150K BTU heaters.

So my question is would adding a 200 Gal storage tank help? or am I better off selling them a second 100 Gal 199K BTU heater so they have a total of 398K BTU keeping up.

 

I prefer a storage tank to the on demand. The on demand machine is going to take a beating there, and most likely not get maintained. Then you are on the hook when it breaks down.
I did two rinnai in a laundromat, non condensing. Works good but the maintenance is a pain in my ass.

 

This reminded me about the commercial laundry I had solenoid issue with?
The demand they put an their industrial machines were pretty intense. They did the laundry for a few of brothels and hotels. They would also regularly wash tarp sections for event Marquees as well as overalls for factories.
The water consumption can be very high, a lot of laundramats here, set up rainwater recovery tanks from their building along with a backflow to give them dual water sources! Perhaps you can upsell this to your client at a later stage?

 

I would prefer the storage tank. Pipe your cold water to the storage tank first it will take the cold shock off of the water heater and boost the recovery rate.

 

I have a customer that has two of those machines. They have one 100 gallon storage tank and one 100 gallon water heater. They also have 3 of those washers. They are able to run all three. And no problems. The water heater is 199k btu

 

(posted by the kid)