Multiple questions on hot water heating system.

JOSYS36

My home was built in 1857. Started out with stoves and 2 fireplaces for heat, and then sometime past 1900 they put in a central heating system. I was told it was steam but the original system was hot water. The original expansion tank was up on my 3rd floor copula. The coal system was removed in 1951 when the present boiler was installed. The system was then converted from Oil to Gas about 1975. When I moved into the house this past August the previous owner said he had the system serviced every year. So far I am not impressed. Because I am mechanical in nature I wanted to know as much about this system as I could. I have loved hot water heat since I was a teen, and I was thrilled that I finally had a system of my own. OK that being said I have some questions. This has been further fuelled by reading Dan's book on classic hydronic systems.



1. The boiler is from 1951. So far it works great and my heating bills are not really that bad for as much space as I heat. If things continue as they do I really don't see a reason to replace it. The previous person who serviced this system recommended to the previous owner not to replace it. That kinda surprised me since he would have been loosing out on money. I know think that he did not know how to proper size a new system and didn't dare touch it. So my question here is should I give thought to putting in something new, or just maintain what I have? There are lots of things that need to be done around this property so I need to budget.



2. I have had pressure problems since I moved in. There was one radiator on the first floor that had no water in it, and 3 upstairs that would not bleed out at all. You would get a bit of air, and then it would stop. So I contacted the guy who serviced this system and he said that the pressure was most likely too low. He told me how to get the pressure back up to 12 to 15 pounds, and with that I was able to get all the air out of the radiators up stairs. I figured that the system must be able to deal with the pressure after the water is heated and expands. I at least knew enough to know that the water will expand when it is heated. So a few days later I went down in the basement to see how things are doing and of course there is water on the brick floor. The pressure was going up to high. So, I then bled the system and got the pressure back down to normal, and then backed off the inlet pressure valve so it would not add water back in until the pressure got really low. Then I did more reading and learned about the steel expansion tank. So I shut things down and found that that tank was full. I was able to pull some of the water out, but I need to make some draining hoses to properly drain that tank. My main question here is I have read that that tank needs to be drained at the start of each new heating season. Is this the proper way to maintain the tank? Or, should I just have it replaced with a new expansion tank with a diaphragm?



3. My system has two circulators installed. Both are on the return line to the boiler. I'm pretty sure this was done since the piping out of the boiler was a pipe maze. From reading Dan's book I found that putting these on the return lines is not the best thing to do. However, is it worth my while to try and have the whole thing re-done?



I have attached a pic of the radiator that is in my office. As you can see the pipes behind it to the radiator in the bedroom above. My walls are solid brick so there was no way they could put the pipes in the walls. Even the interior walls in this house are 2 bricks thick so all the radiators are like this. I actually like it. Pipes are easy to work on, and you get the extra heat of the pipes in the rooms. The pipes also keep the basement more warm so I don't mind that either.



Thanks!!!



Jason

JStar

Heat

Look at that beautiful radiator!



A high efficiency boiler would LOVE your system. A house full of cast iron and radiators is like a free lunch buffet to a mod/con.



The pressure needs to be adjusted to the height of the highest radiator. At 3 stories, plus the height of the radiator, you would require a cold fill pressure of about 20-25 psi. That also means that the pressure relief valve will need to be rated for at least 40-50 psi.

JOSYS36

More Thoughts

The house does have 3 stories but the top story is just a copula. So, there are no radiators up there. My highest radiator is on the second floor. So what should the correct pressure be in that case? Also why would a new boiler love my system so much?



I have included a few more pics of the radiators. There are 14 of them in the house. Some are full size, some are short and wide, and then some are tall and skinny. Just depended on what room they were going to be installed in. What would you say the date these are from is? My guess is early 1900s.



Jason

JStar

Heat

Mod cons are most efficient at lower temperatures. Those big old radiators put out a lot of heat and send cooler water back to the boiler. Cold returns = higher combustion efficiency.



The pressure should be set at 1 psi for every 2.34 feet of height to the top of the highest radiator, plus a little extra for safety.



I've always wanted a plate warmer radiator.

JOSYS36

Guess I should

Well I guess then I should consider replacing this boiler. Now I just need to find someone who is competent to do the install job. I am in more rural IL. Maybe someone from Chicagoland will be of more assistance.



Jason

JOSYS36

Also noticed.

I also noticed that my system does not have an Airtrol Tank Fitting for the compression tank. That probably explains why the tank keeps getting filled with water. I had to drain quite a bit out of it, but the process was nasty without making some drain hoses for it. Also when I moved all my 5 gallon buckets seem to have vanished. Not exactly sure where all of them went.



Jason

JOSYS36

One last question. ( At least I think.)

One last question.



My current system has the thermostats controlling the circulators. So if one side of the house calls for heat one comes on, and if the other side calls for heat the other comes on. When I asked the local guy about things that could be done he said they could be converted over to run all heating season. And then you would attach a temp sensor to the boiler to raise and lower the temperature based on the outside air. I also figured I could just manually control the boiler temp based on the outside temp. However, is there any benefit to having the system work like this? What are the downsides? To me that would be hard on the circulators, but they can be oiled and I suppose I could rebuild each circulator before the start of the next heating season. They remind me a lot of the tractor generators I work on.



Jason

Paul48

Pressure



 A . Calculate the number of feet from the regulator to the highest radiation.                                                                                                                                                                                                                                               

B.Multiply this number by 0.43 and add 3 lbs. This will give the pressure required to raise the water to the highest radiator and keep the system under pressure.

SWEI

outdoor reset control

comes as a standard feature on today's mod/con boilers.  It will increase comfort and reduce fuel use at the same time.  Depending on the system curve and existing circulator sizes, you might do well replacing them with a so-called smart circulator, which will use a fraction of the energy (savings of 75% or more given that you probably have three-piece circulators now.)  The existing thermostats can be hooked to zone valves for use as high limit controls, especially if you have rooms with solar gain, wood stoves, etc.

JOSYS36

Will do!

I'll figure out how many feet that is and use this calculation.



Thanks!



Jason