Vacuum boost retrofit, For 1pipe and 2 pipe steam systems

mikeg2015

PMJ said:

@mikeg2015,



Look up Teco at Factorymation.com. $100+/- and you are in business. I have AB at my factory too. No need for all that.

Looks promising.

PMJ said:

@mikeg2015,



Look up Teco at Factorymation.com. $100+/- and you are in business. I have AB at my factory too. No need for all that.

Cool. Looks like $98 for controller, $33 for cable and $8 for software. Not bad. Could burn that on a bunch of timers and relays really fast. Might be a Fall 2018 project.

mikeg2015

I also don't think it would be too hard to tighten up a lot of system. Most leaks are valve stems and maybe a few unions. So its' just a matter of repacking a few valves. Might be surprised.

I liked the concept I saw elsewhere on the sold system that were 2 pipe but no traps. boiler capacity was equal or less than EDR I think and they used orifice plates to control venting rate.

mikeg2015

Funny... all this talk makes me wonder if I'm looking at this all wrong. My coal system originally had Hoffman #2 vacuum vents (I still have 2 of them, think they work ok). So if i could just find 12 more and add maybe a simple check valve on the Big Mouth... I might be in business.

508steam

@AMservices

Phil53

I've been toying with the idea of converting my hot water system to a natural vacuum gravity return steam system. Since I have more EDR than I need for steam would it make sense to use orifices instead of radiator traps and would I need a cross over trap at the end of the supply main?

jumper

TRV s are better. Instead of natural I'd use mechanical and then I wouldn't need any trap. Big job is insulating pipes.

AMservices

There's a lot to consider before trying to convert your hot water system to a vacuum steam system. I know it looks like you have to easy conversion in front of you. Big supply pipes all pitched to the radiators, return pipes all pitched back to the boiler. There are differences between the 2 systems.
One thing is cross over traps at the ends ( I'd say if there was a vacuum pump used, you could leave them out because the pump is so much faster taking the air out, the mains are cleared and the system can be balanced from the radiator valves. but cross over traps would be needed if you plan to have the steam push air out.
Another thing to look at is where you will need drips. Gravity hot water systems have all supply pipes pitched up and away from the boiler, that would give you counter flow supplies. There would need to be drip every 20' or so on the mains.
It may also be necessary to have drips on the risers.
Instead of orifice plates, think about packless radiator valve. The valve can be your orifice. Much easier to make adjustments and makes the system that much tighter.

Phil53

Current system is cast iron baseboard radiators, copper pipe with monoflo tee's. Really like the simplicity of a gravity steam system with no pump and few moving parts. I would use threaded iron pipe and probably do the work myself with a little help. House is a 1800 sq ft ranch so not real big and no 2nd story risers to worry about. Since the chimney is near the center, I'd probably have two mains off the header and loop around. Total EDR would be less than 300. Would probably heat the basement with the current boiler or may just use hot water from the steam boiler, currently the basement is unheated.

AMservices

If it's a total re pipe, you can put the fittings in at the end if the mains for the cross over traps, try the system without them, then if you think it they should go in, put them in.

Dennis1679

Mr Zdahano has been studying these ideas for a long time. I have seen several prototypes of his systems both in his own house and in a lab. If I was not close to retiring, I would have been selling and installing retrofits to vacuum. His ideas and plans have a lot of merit, and he has been able to use the vacuum to run steam systems as if they had boiler reset, due to the lower temps allowed. He is also quite open and generous with his ideas and experiences, so don’t hesitate to contact him to discuss!

mikeg2015

I’ve also wondered if you could add vapor compression to the system on a residential size scale. Maybe solar panels to heat ground loops during the day and extract that heat at night. Other times use a mod con boiler it’s an indirect tank with 2 coils for supplemental heat.

I hear the centrifugal compressor impreller is relatively large to get the mass flow you need. But that the COP is higher than other refrigerants. Also eliminated the oil. But probably need RO water.

Bill Stocky

Apologies if this question has already been asked, but have each of the various retrofits of the Vacuum Boost system documented actual efficiency improvements?

izhadano

Hello Bill,
You can check NGRID study winter of 2013-14 confirming fuel savings of up to 50% from retrofit of steam system into vacuum.

For follow up, the annual heat degree days and heating cost data are presented for the retrofit of a single-pipe SHS on the second floor apartment of a two-family house starting in the winter of 2012-13 shown in recent article in FacilitiesNet, Figure 2 . Because no changes were made to the original single-pipe heating system on first floor, it is used as a base line to compare results. In the winter of 2013-15, a full retrofit into a vacuum system saved roughly 50 percent of fuel gas. A partial “vacuum boost” retrofit saved roughly 30 percent at a fraction (10 to 23 percent, depending on the schematic and condition of SHS) of the full retrofit cost — all materials, tools, and controls are shelf available.

We'll do our best to collect/analyze results from later retrofits.
Please, let us know if you have more questions.

Thanks,
Igor

Bill Stocky

Igor, thanks for the quick response. I noticed that in the pictures at the beginning of this post that there were two vacuum pumps in what was obviously a residential home installation. In other pictures of your retrofits there was only one. Why is that? And with them being piston pumps it is absolutely mandatory that no liquid gets into them.

AMservices

I installs 2 vacuum pumps only for security purposes.
Even though Mechanical vacuum steam systems have existed for over a 100 years, Designing and installing them is still new to me.
If I miss something in my design where the pump Got damaged from sucking steam or hot condensate, I wanted a nother pump ready to go. These vacuum pumps are medical grade Lab equipment, designed to run for months without being shut off And can handle environments with high moisture.
I have seen these pumps vomit water and keep running.
By the time I got to my 3rd retrofit, my faith had grown in the pump and was confident to rely on only one pump.