Installation & repair details for electric & LP gas residential steam shower or steam box systems:
We compare the design and features of a small Mr. Steam electric steam generator and a completely different LP gas powered steam box system. Both of these systems are installed at properties in a city in Mexico but both designs are also wide-spread and will be found in other countries.
This article series describes in more detail the installation of a residential steam generator in the shower of an existing home. We report what went well, how successfully the steam generator operated after installation.
We continue by describing repair of a new but failed steambath steam generator installation: what went wrong, what trouble it caused, and how steam generator problems with small residential steam generators might be diagnosed and repaired.
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Also required are a water supply and a power source, usually electricity, occasionally natural gas or LP gas to power the steam generator, and a properly-enclosed and safe space into which steam will be generated.
Photo: a large steam bath in Iceland - Wikipedia 2017/09/10
Both private and public steam rooms or residential steam showers or "steam baths" have been in popular and widespread use since Roman times.
Provided that the steam generator installation is performed properly and provided that basic safety procedures spending time in warm steamy room can be both relaxing and healthy.
Thermotherapy soothes symptoms such as muscular strain, heaviness in the limbs, edema, loss of appetite, and constipation, whereas the essential oils of the plants used have an immuno-stimulant, antiseptic, and antiphlogistic effect.
If applied under the guidance of an experienced person, during the late childbed, the bakera can be regarded as an effective and safe method for recuperation after child birth. - (Zumsteg 2007).
Watch out: check with your doctor about any health limitations that would affect your individual case before spending time in any steam box or steam shower or steam room. (Press 1991)
Saunas, steam baths, and whirlpools—popular fixtures at health clubs—are safe means of relaxation, if used prudently. But ignoring the recommendations for moderate, commonsense enjoyment of these baths may expose users to health risks.
Watch out: for safe installation of this or any other heating equipment, follow the manufacturer's instructions for both installation and use of the steambath, and make sure that your equipment and its installation comply with local plumbing and building safety codes.
Sauna therapy has been used for hundreds of years in the Scandinavian region as a standard health activity. Studies document the effectiveness of sauna therapy for persons with hypertension, congestive heart failure, and for post-myocardial infarction care. Some individuals with chronic obstructive pulmonary disease (COPD), chronic fatigue, chronic pain, or addictions also find benefit. ...
Overall, regular sauna therapy (either radiant heat or far-infrared units) appears to be safe and offers multiple health benefits to regular users. One potential area of concern is sauna use in early pregnancy because of evidence suggesting that hyperthermia might be teratogenic. [Teratogenic means that there is a risk of harm to a developing fetus - Editor] - (Crinnion 2011)
The manufacturer of any steam generating system will provide tables of steam-space dimensions along with recommendations for the steam generating capacity you will need.
In this article we describe installation of a Mr. Steam MS90# 5KW steam generator, the smallest in the company's product line and designed for a 100 cubic foot area. Mr. Steam MS-series steam generators are provided in models up to 30KW that can handle a room with an adjusted volume of 1275 cubic feet.
Steam room volume = room length x width x height
in feet or meters
Photo: the shower area wall has been squared-up in preparation for installing gasketed glass enclosing top window and entry door to make this space into a steambath.
[Click to enlarge any image]
Adjusted Steam Room Volume Calculation
Watch out: in a cold climate, steam rooms constructed of materials that conduct a lot of heat away from the space, such as solid concrete and ceramic tile require more steam generator capacity.
It's easy to calculate the cubic feet of a steam shower but if you fail to consider the construction materials, and if your shower walls are built of ceramic tile on solid masonry, the steam generator you select may be too small to generate sufficient steam for the space.
The Mr. Steam® MS90E 5KW steambath generator can provide steam for an adjusted room volume of 100 cubic feet. That was about 15 cubic feet greater capacity than the actual volume of the steam shower planned for the customers' home.
That little extra capacity was important when we learned that in the customer's home the existing shower stall was in a building constructed of solid concrete with ceramic tiled walls.
Steambath spaces constructed of materials that conduct less heat away from the space, such as spaces using acrylic or synthetic wall coverings over hollow framed interior walls may require less steam generator capacity.
Had the home been located in a cold climate like northern Minnesota we'd have needed an additional 110% capacity.
Watch out: the most-detailed instructions we found for choosing the right steambath generator model were inside the installation manual for the steam generator - a document that arrived with the steam generator after its purchase.
Be sure that you have complete sizing instructions before buying your steam generator.
Otherwise you might discover too-late that simply measuring the cubic volume of the steam room size may not give the best answer to steam generator size.
To make an existing shower room an effective steam shower or steam bath space you need more than adequate steam generator capacity. These additional details may make a difference to the happiness of the steam shower users:
The shower space needs to be well-sealed against steam loss through a space between a typical shower enclosure wall and the ceiling as well as steam loss through a leaky shower stall door.
In the small shower stall we illustrate here, modifications included:
If you omit these enclosure details, even if the steam generation rate is adequate you may find that you are soaking other building areas with steam condensate on surfaces that were not designed to be so wet.
This topic has moved to a separate page now found at Mr.STEAM iTEMPO CONTROL & STEAM HEAD INSTALL
For most steambath products a separate wall control is used to control the steam generator on/off, temperature, time-on and other features.
The installation instructions for the wall control will be separate from the instructions for installing the steam generator itself.
Watch out: start by reading the manufacturer's instructions, both to understand the proper installation procedure and details, and also to discover what additional electrical, plumbing, or other supplies you need. I know, I know, like I was, you were taught that the instructions were just used to kneel upon while working on low plumbing connections. Not so.
Here our crew boss is actually reading the MS90E steam generator installation instructions from Mr. Steam. We found the installation instructions from Mr. Steam were clear and complete you can see this example Mr. STEAM GENERATOR MS90EC1 INSTALLATION MANUAL [PDF].
I will not repeat the details of installation of this steam generator since they're provided by the manufacturer's document. Here are some highlights that you must consider:
Incoming Water Control Solenoid Valve: Above: the Robertshaw S-53 K-77451 100479-1 24VAC 10W 246C15 solenoid valve that controls the entry of water into the steam generator.
Wires: Gray and White with gray stripe. In a pleasing irony this valve, made at a Robertshaw® plant in Mexico, traveled to the U.S. to be assembled into this steam generator, then returned for installation in Mexico.
Low Voltage Transformer: Above: the 40 VA low voltage transformer (Hartland Controls, RockFalls IL USA) providing power to the circuit board. Wires: Blue, white with blue stripe (power out to the control board), and two black power-in wires from the contactor switch.
Power Connector - Contactor Switch. Above: the power connections at the steam generator contactor switch. Incoming (black) power wires are on the left.
240VAC power to the contactor switch is fed out to the heating element (blue wires).
A red wire and a white wire with red stripe from the control board activate the contactor switch that in turn will power the heater.
Relief Valve: Above: in compliance with model and local plumbing codes, any pressurized vessel including the water tank for a steam generator must have a temperature and pressure relief valve.
The Mr. Steam MS90E sports a Watts No. 315M2 TPR valve that will open at 15 psig or more.
The relief valve installed on a heating appliance must also be capable of venting energy, hot water, or steam at a rate that exceeds the energy input rate of the heating appliance. This valve can vent 375 lbs/hr.
Properly installed a relief valve that could open to spray hot water on a bystander must be piped to 2" from the floor or to a visible location at a suitable drain point.
Watch out: Never pipe a TPR valve to a location where you cannot see the end of the drain line since failing to observe that the valve is leaking can lead to a clogged TPR valve and an explosion. See BLEVE EXPLOSIONS for details.
Also see RELIEF VALVES - TP VALVES - our article series describing the installation, inspection, and testing of temperature & pressure relief valves.
Above: the manual drain valve for the steam generator open for testing. Very hot water spills on this outdoor tile patio and drains to a nearby floor drain. Hot water should not be drained to a spot where people might come into contact and risk scalding burns.
The feedwater quality recommended by Mr.Steam® in the installation manual for this steam bath generator includes a hardness between 8-85 ppm (0.5 - 5 grains of hardness per gallon).
Since the water supply where this steam generator was to be installed was 25-50 times higher in hardness than recommended, the prime contractor was emphatic that a water softener should be installed.
The Fleck water softener installed for this property is shown in the photo.
Installing a rooftop water softener meant adding a pressure-boosting water pump to move water up from the rooftop water tank and through the water softener as well as through water filters and a UV system that were installed downstream from the softener itself.
We installed a Grundfos SCALA2 - SCALA2 Informacion Basico [PDF] bomba de aumento de presion, no usa tanque external that you can see in the lower right corner of the photograph.
The Mr. Steam MS90E5 KW electric residential steambath generator requires a 240V circuit that can deliver 21Amps. That means installing a 25A 240V circuit. Most homes in Mexico including the property where this equipment was to be installed use very modest electrical service. The entire home was served by only a 40A 240V panel.
Adding electrical circuits for the steambath generator, water pump, water softener together meant increasing the electrical panel size and, no surprise, running new electrical circuits to the areas where the equipment was to be installed.
Larger, higher-capacity steambath generators in this same product line can require a 240VAC circuit delivering up to 125Amps (for the MS SUPER 6E, the largest steambath generator in this product series).
Above: installing a steambath in an existing shower permits additional comfort features such as the ability to follow steam treatment with a hot or cold shower.
Because we had installed a new water pressure boosting pump on the rooftop above this existing shower a new shower head and the boosted water pressure made this shower functional.
Above, a Tiemme PN15 pressure regulator and pressure indicator gauge have been installed on the cold water inlet line to the steam generator.
The regulator was adjusted to deliver about 20 psi or 1-4 bar.
This topic is now provided in a separate article found at STEAM GENERATOR OUTDOOR INSTALLATION
Watch out: The manufacturer of this equipment expects you to install it in a clean, dry, location protected from the weather.
This topic is now found at Mr.STEAM MS90E TROUBLESHOOTING
Below we include contact information for Mr. Steam as a steam generator sold by that manufacturer (Sussman Automatic) is described for this article series.
For our complete list of references, manuals, and research on the health effects of steam baths, please see STEAMBATH GENERATOR SOURCES & HEALTH RESEARCH
This steam generator is now described in a separate article at PROPANE POWERED STEAM GENERATOR
Continue reading at Mr.STEAM iTEMPO CONTROL & STEAM HEAD INSTALL - wall mounted controller, or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
Or see DIAGNOSE & FIX HEATING PROBLEMS-BOILER - home
Or see SPA / HOT TUB HEATER REPAIR
Or see STEAM HEATING SYSTEMS & CONTROLS - home
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DOEs ANYONE KNOW THE PROPER SETTING FOR A HONEYWELL PA-404-A 1009 PRESTROL CONTROL FOR A WEIL-MCLANE STEAM BOILER - Rick 9/11/11
Rick the exact pressure needed varies by installation but in a low pressure residential steam system the pressure range is usually between 0.2 and 0.4 psi.
what's the term they call the 2 steam pipes that form an H above a steam boiler. in other words the pipes from both sides of the burner connected together?THANKS,Walter - 9/25/11
Walter: sorry we couldn't give an instant reply; sometimes the volume of reader questions is considerable and takes some time to get thorough.
I am guessing you are referring to the steam header or manifold piping that allows steam to enter more than one steam supply line or riser.
A second piping configuration that will be along side, not above, the boiler is the Hartford loop - a loop of piping sort of like an upside down trap that prevents water from siphoning out of the boiler should there be a leak in the condensate return line.
Wow, what a great web site. I am trying to identify a vessel on the side of an old National steam boiler/furnace. It is about 12-18" tall, about 8" diameter and is attached to a manifold in the side that is about 12" off the floor. It is heavily rusted. The boiler is an old coal fired converted to oil. Can I send you photos? Thanks, Stephen firstname.lastname@example.org or strentsch 10/4/11
sure Mr. Strentsch,
use the CONTACT link found at page top, left, or bottom to see our email and send along some sharp photos and we'll be glad to take a look
I blow the system down regularly and then make up the water in the sight glass. However I seem to be using significantly more water then years past whereas I'd top the sight glass every couple of weeks in the past compared to every other day now. What do you think the problem is? - Tom C 10.27.11
Tom C: a common reason for increased water consumption in a steam heating system is one or more radiator steam vents that are not closing properly. Check also for a leak in the condensate return line.
I’m happy to have found this website. I’m getting back into heating and cooling and need to prepare for higher license. Question: Is there a DVD collection you recommended as an additional studying tool? I see that Harold J. Frost, Frederick M. Steingress, Daryl R. Walker’s collection is close to 600.00 which is very steep for my pocket. Would you happen to know of a website or cheap place I can buy such DVD or a CD? If not these guys than another author is ok. Thanks for the feedback. Kym 11/23/11
Kym if you are looking specifically for information on steam heating I'd pick up any of Dan Holihan's books on steam heat. He's the best.
The HomeServ tech just left after installing a new auto water feeder, and the PSI gauge on my steam heater is off the chart, over 30 PSI. I shut it down and called HomeServ and they said leave it on and they'll come in the morning. How do I lower the PSI myself so I can leave it on tonight and my little kids (two with strep) don't freeze? Thanks! 2/22/2012
Watch out: If the PSI gauge is showing abnormal pressure and the gauge itself is working properly the system is unsafe and should be shut down. Call someone else and fire that tech - from your description the system sounds unsafe
I HAVE AN OIL BURNER HOT WATER SYSTEM MY EXPANSION IS DRIPPING WATER OUT THE AIR VALVE STEM AT THE BOTTOM OF THE TANK SHOULD I REPAIR OR REPLACE - Mike S 10/12/12
Mike, an air valve stem is replaceable, I would tr that first. Check also for abnormal system pressure ( an unsafe condition). But if the internal bladder of the tank has burst - another explanation for finding water at the air pressure adjustment valve, then most likely you need to replace the tank. You'll know this condition because the tank will become waterlogged, heavy, and ultimately the boiler TP valve will drip (another unsafe condition).
I have a one pipe steam system. My dining room radiator air vent was just replaced because the old one was leaking profusely (damaged my floors). The porch radiator air vent was also replaced because of too much steam condensation in the room, but now the open/close valve is leaking at the base. The radiator upstairs in middle bedroom is banging and clanking. The pipe that runs along the basement ceiling (finished basement) also bangs when the heat is coming on. My plumber cannot really give me an answer. Any suggestions would be appreciated. Thanks p Rita 11/21/12
If you search InspectApedia for
BANGING STEAM PIPES
you can read about the diagnosis & cure of this problem
About the leaking valve - unfortunately that means you need another service call.
cleaned on a vav [?] system is leaking close the cilanod [solenoid ? -Ed] valve need to be replaced- Anon 11/23/12
See RELIEF VALVE LEAKS for procedures to diagnose and fix leaky TP relief valves.
Pressure on gas steam boiler was rising far too high, so high that the pressure relief valve released twice when it hit 15 psi (as it was supposed to do). Good buddy who really knows his stuff checked everything from pressure valve to pressuretrol. Nothing . He then checked "pigtail" and found blockage .Problem solved!! - Ken 11/24/12
Thanks for this note it may help other readers
My building uses steam heaters. I have no control over the heat in my unit because the thermostat is controlled by my landlord/owner who lives above me. However I have a small 1 bedroom with two heating units so even with all of the windows open, it can still get very hot. Is it okay for me to completely close the "open/close" black knob valves on my units or will that cause problems for the whole system? My landlord had previously told me not to touch the valves... Emily 12/10/12
Yes if the radiator control knob is not jammed or frozen you can try closing it partly or fully; radiator control knobs are intended to be a homeowner-resident-operator control. But if the knob is not easy to turn, don't force it as you might end up with a leak.
I have 2 yr. Boiler. It hisses like venting steam off and on loudly. Seems like when heat comes on venting starts until off. -Mr. Ed 12/28/12
Steam boilers include steam valves that hiss; we need more details.
I am having a pressure problem and it looks like one of my relief valve is leaking or letting the pressure out would this keep my boiler from running. It seems to be shutting off and I need to set the pressure all the time. is it as simple as changing the valve and resetting the Pressure? Rick 1/3/2013
See RELIEF VALVE LEAKS for procedures to diagnose and fix leaky TP relief valves.
II have a pressure of 28 psi and water is coming out of my return how can i lower the water pressure from my steam American standard boiler - Ronald 1/13/2013
Watch out: If your heater is a residential steam heating system it is operating at an abnormally high temperature and is unsafe. Turn the system off immediately and call your heating service company.
If your heater were a residential hot water heating boiler (hydronic heat) its pressure might be close to the upper end of normal operating pressure - and the leak at the valve could be due to a valve problem or to any of quite a few other causes. See RELIEF VALVE LEAKS for procedures to diagnose and fix leaky TP relief valves. See the links just below for information on how the steam heating system pressure is controlled and set.
(Mar 23, 2013) home able said:
Oil-fired steam boiler was functioning properly upto two weeks ago, now doesn't fully run to designated temperature on thermostat (digital). It will stop a degree or 2 short of desired setting even though thermostat says boiler is running. Why?
I'm not sure what's happening with your system. IN general the gauges are not lab grade precise. It's possible that your gauge or its sensor port are debris clogged. Try tapping gently on the gauge to see if the needle moves. Also watch the gauge to see its reading throughout the operating cycle.
(Apr 1, 2013) Luis said:
I have a gas bolier which continues to overflow. The sight glass floods even some pipes that run though the floor ang o up the wall with a steam trap a gauges at the to of the pipes. I called a company but they have not been able to find the problem.
Luis if the steam boiler keeps overflowing, or flooding, most likely the water feeder is out of order.
(june 19, 2014) anonymous said:
I have hot water baseboard system boiler in my crawlspace (.Basement) im thinking about replacing the boiler with a horizontal warm air furnace adams furnace. I keep getting freeze ups and they are very difficult to repair. The furnace adams make is supposed to be 95 percent efficient. Plus the fact there are no pipes to freeze is the warm air furnace the way to go? Thanks paul
You're commenting about hot water and hot air heat on a steam heat article - so this may be a bit confusing to other readers, but in general, conversion to another heating method is fine if you can bear the expense; each heating type has its pros and cons so IMO there is not a single "right" answer. Keep in mind that when you change from steam heat or hot water heat to forced warm air heat, your costs are much greater than just the heater itself as you have to install a heat delivery system : air ducts and registers. That can be convenient in some building designs and quite costly in others.
(Oct 16, 2014) Antonio said:
I just installed a 299 MBH gas fired steam boiler and connected to an existing system serving the second floor of an office building, approx floor area is 2,600 sq ft.
Existing EDR calculated as approx 900 sq. ft. The boiler started up successfully yesterday and I have been testing it ever since. Everything seems to be working fine. My question is what would be the right pressuretrol settings: I am using 1 psi cut-in and 1 psi differential and everything seems all right, but I may be missing something, maybe the boiler could work more efficiently with a lower or higher cut in pressure.
(Dec 15, 2014) Kevin M said:
I have a gas-fired steam boiler that has worked flawlessly since its installation six years ago. Suddenly it is overfilling. I let out several extra gallons a day to reduce the level in the sight glass. Should I replace the automatic feed? It is attached to the hot water heater, unlike previous installation I have had in other houses where it is connected to the cold water line. I sit possible that excess pressure from the expansion in the hot water supply line is forcing water past the automatic feed? What could cause this condition?
Over-filling of a heating boiler is indeed usually a problem with the automatic water feeder, more rarely leaks into the boiler from a tankless coil.
(Feb 15, 2015) Beverly Streeter said:
I live in a 16 unit apt complex. What make the heat clan and banging?
See the banging pipe diagnostic and repair suggestions at BANGING HEATING PIPES RADIATORS
(Apr 9, 2015) george said:
steam boiler heater runs for about 15 minutes then it cuts out
George I'm stuck on this one with no onsite data; could be related to heating of components, clogging of a filter, I dunno. It's time for an onsite heating service tech.
DO NOT keep pushing a re-set button. That's unsafe.
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