Steam Boiler - Oil - Tankless Water Heater

84maple

Hello. Can anyone help me with these questions please? My boiler comes on every 2 hours or so just for about 30-60 seconds, I assume to heat water. It is just me and I am not running hot water very often - I am burning oil unnecessarily? Is there a work around?

Also, no issue with hot water downstairs - never runs out for shower - but runs out quickly upstairs, cannot get a bath hot. Ideas?

Note - all mechanicals in house when I bought 15 years ago. Age probably closer to 25.

Thank you!
Laurie

pecmsg

That 30 - 60 seconds sounds like maintaining boiler temperature not Hot Water.

We need to see the piping for 1st 2nd floor to figure out why you're running out.

Where is this located?

Jamie Hall

Pr3esumably by tankless you mean a coil in the boiler that heats the hot water? Very common -- though not necessarily the most efficient arrangement. But not worth replacing unless and until something else fails...

The very short cycle you mention, however, suggests that the device, called an aquastat, which keeps the boiler warm enough to make hot water, but so hot as to steam, may not be functioning properly. It could be just an adjustment -- but it could also need replacement. Neither that expensive nor that difficult to do, and if you get adequate hot ware downstairs I'd let it go until you get a technician in to do the yearly cleaning and maintenance on the boiler, and have him or her look at it.

On the lack of hot water upstairs, but not downstairs -- that's a bit odd. Unhappily there are a number of reasons why that could happen. The first thing I'd look for, though, is this: is there a single handle faucet on that upstairs tub? Those often give trouble. Try this: set it to pure hot, and see what the water flow is like.

Big Ed_4

Your boiler is maintaining temperature to keep the coil bathed , incase there is a draw of hot water . The coil is a copper heat exchanger , minerals can coat the inside or the outside of the heat exchanger and impede the heat transfer .

Cold water enters one side of the coil , picks up the heat and flows out to your shower . If water flows though the coil too fast the temperature may not be hot enough . And the first draw of hot water may be scolding . I am assuming the shower head upstairs flow rate is higher than downstairs . But newer shower bodies today from its engineering needed can also fail to create a cold water bypass . The bath spigot on full would be 5 GPM. With clean coil 2 GPM flow rate is what you need . You can fill tub up slower . This is the bacics ,there are other factors with coil water heating

To gain hot water volume and more of an even temperature a storage tank will work better . Since you already have the coil or heat exchanger the first system to look at is an Aqua Booster . The slowest to recover but normally the lest costly system . You want to size the tank to your largest load which may be the tub .

leonz

Hello Laurie,

I spent part of my growing up years in a one pipe steam apartment over my parents grocery store in my early years.

Your boilers burner and the firebox fire tubes are probably overdue for a cleaning and having the boiler flushed out and the mud leg emptied of sediment by a steam licensed plumber only if this has not been done.

The same steam licensed plumber would also add water treatment to the fresh water pumped back into the boiler as well after the boiler is flushed out and wanded clean.

If the oil burner is 25 years old it may be best to replace THE OIL BURNER ONLY it due to its age and use a smaller oil nozzle. The burner will run longer and you will burn less fuel per hour.

If your steam heating system is 25 years old it is probably best to have the same plumber check and replace the pressure trol, the pig tail, the pressure gauges, and check the water feeder to see if it needs to be replaced with a new one with a low water cut off function as well as any bad radiator vents and check to make sure the radiators drain back to the boiler correctly to the header pipe in the basement and add a main vent if it does not have one and add a drop header to the boiler to make dry steam faster to heat your home.

If your home does not have water saving faucets it may be time to think about having the new lower flow faucets installed to save water and fuel too as filling a tub take a great deal of water and heat energy.

If your domestic coil in your boiler is rated at 5 gallons per minute in flow rate it doesn't take long to cool down the water in the boiler and you may just need a new low flow shower head and faucet for the tub.

You should also ask the steam licensed plumber about adding domestic hot water storage for you and what the best way to do this is for your situation.

I hope I have not missed anything; I also am not trying to spend your money, but you have an excellent heating system that still works and may just need to be serviced and cleaned and any bad parts replaced and installing a drop header or a double drop header will provide you with dry steam faster and heat your radiators more quickly and they will stay hotter longer if I remember my basic physics correctly.

84maple

Thank you all for this great information. This is very helpful! The first thing I need to do is find a licensed STEAM plumber. I have my boiler cleaned by a licensed plumber but not specifically licensed for steam. I am told steam systems are not common and my steam issues seam to be perplexing....The system is 25+ years old, different parts replaced along the way but the ones mentioned do not sound familiar. It has been flushed. I think this information will really help, once I find a steam plumber. Thank you!!!!!

ethicalpaul

Probably don't look for a "plumber", look for an HVAC contractor who works with steam. The word "plumber" is always going to tend to steer you in the wrong direction, IMO