By: Jessie

Jessie — Sat, 10 Sep 2011 01:22:31 +0000

I manage (2) hotels as the Chief Engineer – I am having some opportunities with no cold water on all 5 floors. I played with the balancing valves on the 4ht floor, adjusted the 2 symmons mixing valves temps set at 120 – I have 2 circ pumps running 24/7 the timers have been by passesd why? And how can I begin this process of eliminations I am getting complaints at all hours. Please assist me with good pointers to get this fixed.

Thank you,

By: Chin Joong onn

Chin Joong onn — Mon, 04 Apr 2011 07:25:20 +0000

Dear Sir,
What is the international standard of when you turn on the hot water and within how many second you will get the hot water. We are having 9 sec.
Please advice.
Thanks.
Chin Joong Onn.
Chief Engineer

By: Spike

Spike — Wed, 03 Feb 2010 13:25:47 +0000

I have 2 different hotels, however the new 22 floor hotel has been open for a year now and we have had constant problems with the domestic water – cold backing into the hot, hot backing into the cold etc. Obviously the water problems tend to happen during times of lower water use – during higher volume days we tend to keep enough water moving for the system to be happy. We have a two zone system with PRV’s to maintain pressure at each zone then to make matters worse we have mixer valves installed at each sink in every room & to add to this within the shower valves are Pressure balancing valves. Now let me throw one more thing into the line-up here – on the upper floor mechanical room at the domestic hot water boilers are dual Symmons Temp mixer valves for setting the water supply temp (OK hope everyone followed that). What I have found is that the piping when installed was not sufficiently flushed, I am finding metal shavings getting caught in PRV’s, “Y” strainers, mixing valves, shower valves, just everywhere. This is my procedure when I run into the problem:
1) Basement mechanical room – make sure the cold and hot water pumps are pumping close to the same pressure up the tower.
2) Check the different zone PRV’s- make sure the pressures are close to the same, I like to have my cold water slightly higher then the hot (it’s more acceptable to customers to wait a minute for the hot water then to try to figure out why there is no cold water) I like to change the setting on the PRV’s for each zone just so I can make sure they are working – as we are speaking I have 3 prv’s not working that I have to pull today (like normal suspect debris causing the issue).
3) If it’s hot backing up into the cold – I go to the upper floor mechanical room and check the cold water side of the Symmons temp mixers, if the cold water side is hot I Turn the mixer to as cold as it can get and go to the affected floors and run as much water as I can (both hot and cold to flush the problem out – you’ve got to get the hot out of the cold system, then once you’ve got the hot out of the cold readjust your mixers to maintain the correct temp usually 120 degrees.
4) Then try to determine where the problem is- perhaps you found the problem when you check the Basement pumps or the PRV’s that may have had too much differential pressure or not working at all, was it just one zone affected and if so what group of rooms – were the rooms spread out to different risers? Knowing the rooms can tell you if it was a under sink mixer within that riser that could have been causing the problem. You have to isolate where the problem is coming from in order to determine what is causing the problem, THEN you can resolve it. Keep in mind the “Needle in a haystack” scenario if you have a setup like mine – the culprit tends to change each time it happens – other then the primary culprit with is usually a debris problem.

Note to James’s problem above: James I would look at the size of the circ pumps, sounds like they may have been undersized. Now it this is a problem that just started to happen I would consider the age of the circ pumps and that perhaps the impeller has worn or become damaged – or perhaps the wear rings internally have opened up- you might need to rebuild the pumps, are you able to maintain pressure sufficient to get to the upper floors? (Remember it takes 1psi of pressure to climb 2.31 feet of height and that you want to add to this figure to the 40-50 psi that you want coming out of those upper floor fixtures so the guest can have a nice shower). Good luck. If I can be of any assistance you can email me at spikesamuels@yahoo.com

By: Rick Lambeth

Rick Lambeth — Wed, 21 Oct 2009 12:04:32 +0000

The hotel has sporadic hot water complaints in mid rise and high rise sections. No ryhme or reason as to specific risers or time of day. The hotel has 12 risers and 30 floors serving approx 500 guestrooms. One return line comes down from the 30th floor. About 6 years ago, the hotel replaced original balancing valves from each riser on the 30th floor feeding the return line with Griswold Autoflow devices. They were sized at 1 GPM each with a 2-32 psi insert.

By: james k williams

james k williams — Tue, 08 Sep 2009 12:08:31 +0000

I work at a hotel our probelm is no water in showers and tiolets on 4th & 5th floor rooms when we are at 100%.Hotel is only four years old circulating pumps push water to 5th floor.Only happens in the morning when everyone takes a shower can you give me some advice?

By: Mark Robison, P.E. » Blog Archive » Hotel Hot Water Recirculation Systems

Tue, 30 Dec 2008 21:16:00 +0000