Steamer Drain System ?

[fishheds]

I need to bounce this situation off you guys.I work for the county school system as cafeteria equipment tech and one of my schools just got a new floor drain system installed.That's why I'm here.
It was ran in 4" PVC.We were of the understanding cast iron would be used for the section the steamer and steam tables dumped into but somewhere along the line the whole system got ran with PVC.Now the task of insuring hot water(170*+) doesn't get dumped into the line has fallen upon me.Normally I'd just say the rinse solenoid will take care of that,but the steamer(VSX24G5) is 14 years old, the rinse solenoid fails sometimes and I've also got the steam table to consider.I REALLY don't want to melt the pvc,especially since I feel the damn system was plumbed incorrectly to begin with.I made my concerns known in no uncertain terms and we're now in a standoff with the plumber and school stars Tuesday.
What do you gents think would solve my dilemna.I'm considering teeing the steam table drain(3/4") into the steamer drain(2" coppper) and installing a second rinse solenoid/probe assembly just downstream of this,effectively make the steamer drain rinse redundant.I don't THINK the steam table will be much of an issue because of the amount of water involved and the distance to the drain it'll travel beore it dumps.
Any suggestions?

[ECtofix]

I don't understand your intentions in coupling the steam table drain with the steamer drain, nor the redundant valve and probe. If the drain system can't handle hot water (near 212 degrees from the steamer during blow-down), then the plumbers need to fix that. I'm no plumber, but I'm certain there must be stipulations within building codes that require properly installed floor drains in commercial kitchens. Steamers, dish machines, combi ovens and steam tables can easily exceed the temperature limits of standard PVC.

I'm not certain what you're refering to as a "rinse" solenoid valve. All steamers employ a condensate (or "quench") valve that runs a spray of cold water to condense steam as it enters the unit's drain system. Without it, heavy clouds of steam emanate from the drain and condense on anything of lesser temperature (other equipment, the hood system, etc.). I think Vulcan uses a thermostat to cycle that water on and off. Some manufacturers merely couple it's operation to run continuously during the cook cycle. The quench valve also serves to prevent pressure build up within the cooking cabinet. Otherwise, it's doors may tend to blast open when the door is unlatched. On some steamer designs, this can be a alarmingly potent release of pressure that can be the catalyst for accident or injury.

The other water-supplied solenoid valve is to fill the boiler.

Of course, the boiler's drain (or "blow-down") solenoid valve releases water that WILL be at 212 degrees. If the kitchen staff are operating the steamer correctly, then they WILL drain the boiler each day to dump the water that's become mineral-enriched through that days use. In a pressurized boiler, the blow-down will cause a rapid and turbulent blast of water necessary to influence any mineral sediment to leave the boiler.


I'm sure you know all of this, but the steamer is what it is. The manufacturer states the design of IT'S drain to offer the least restriction to where it expells to a floor drain. Any modifications otherwise will affect it's operation and shouldn't be attempted.

The building contractor needs to ensure the floor drain can accommodate it.

[SFhvacguy]

That drain will not handle it. I maintain a couple steam boilers at work for clothing Alterations equipment etc. If that solenoid fails that PVC is going to be cooked, plus its going to fall back into your hands as YOUR problem. Get the plumbers to do it right, if not, get it all in writing.