Category: Basement Mechanical

Replacing the boiler, hot water heater, supply plumbing, and installing a whole-house water filter

Mechanical Room Panel

We finished the first half of the mechanical room panel last weekend, which includes the water filter and heater and a space the future boiler will occupy. The second half of the panel will hold the manifold, pump, and expansion tank for the radiant heating system. I couldn’t build it until the old water heaters were out which, predictably, required the new water heater.

Before

Before

Tuesday morning, Sarah’s dad Mike and I got the two old water heaters disconnected and moved over to the scrap pile. Then we marked out the location of the studs to attach to the wall. After the door delivery, he and Dean ground the brick wall smooth with angle grinders while I cut the lumber to size. I finished grinding down the wall Wednesday and put up the framing. I put sill gasket behind each stud to prevent moisture from seeping into the wood and attached them with Tapcon screws. I found that in several cases the screws wouldn’t go all the way in, despite using an air compressor and vacuum to remove dust and re-drilling the hole several times.

After

After

I discovered the best solution was to drill the holes as I had been with the rotary hammer, then come back and re-drill the holes with the drill bit that came with the screws. Even though they were both 5/32″, something about the included bit worked better. With everything in place, I came back down after dinner and filled the cavities with spray foam. I just need to cut back any places the foam expanded past the front of the framing and it will be ready for Lester to install the manifold panel.

Spray foamed panel

Spray foamed panel

The only remaining item on my mechanical room preparations (aside from cleaning up the huge mess I’ve made) is to run a short length of EMT conduit from the junction box over to the panel and fish a 15 amp circuit for the radiant system.

Mechanical Room Plumbing

For the last couple of months, with the exception of renting a trailer and picking up the windows when they came in, we’ve been working on the mechanical room in the basement. The first step was running new gas line, then we ordered the water heater and whole-house water filter, prepped and framed the first wall panel section, spray foamed it, and covered it with plywood. We also ran a new electrical conduit from the circuit panel to the mechanical room and installed a light and gfci outlets.

Panel framing and spray foam

Panel framing and spray foam

Once we had the panel and parts ready, the next step was to start assembly. The water filter consists of a pre-filter, main filter, and post filter, that are all connected in series, with a bypass around the whole thing. There is a valve before, after, and in the bypass to allow for filter changes without leaving the water shutoff. The challenge was fitting this long chain onto the half of the panel, since the other half is reserved for the boiler. The plumber initially had a setup where half the filter was sticking off one side, but I was really hoping to put a wall there so that I had room for a little workshop in the basement. I also wasn’t thrilled with how it was all mounted. I decided to redo it, even though it was already soldered together.

Initial filter install

Initial filter install

This past Saturday, with help from my brother-in-law, Rob, and my father-in-law, Mike, we got the water filter re-configured with the valves vertical rather than inline with the filter. We also got the venting installed for the water heater and the water heater connected to the filter. Sunday, with Dean’s help, we connected the panel to the existing water supply and plumbing, replacing the incoming water line, the spigot and starting the new runs up to the second floor. After checking all the solder joints for leaks and adding more nylon tape the pre- and post-filter housings, we turned on the water heater. I took a shower in hot, clean water and we drank several glasses of the best tasting tap water I’ve ever had.

Revised filter plumbing

Revised filter plumbing

Like all projects, it wasn’t without its share of frustrations. Just for the plumbing install (not counting the panel build) there were nine trips to the hardware store. In the future I’m going to stock up on ¾” 45° elbows since they seemed to be in perpetual short supply. Drilling through the wall to install the vents was a challenge. I had expected the plumber to bring his hole saw, but when he forgot it I wound up buying bits and even a new drill, since my rotary hammer is SDS-plus and the local stores don’t sell hole bits or a chuck for it.

New water heater

New water heater

As is often the case, I’m grateful to the friends and family that made the project possible. A big thanks to Mike, Rob, and Dean for all their help! With the new water heater installed I can finally get the old one out of the way and put in the second panel section. That will make way for the boiler installation so we can have heat this winter.

Mechanical Room Preparation

With the hot water heater question sorted, I need to get the area of the basement that the water heater and boiler are going into ready. Eventually this will be the mechanical room… when we frame out the basement, after we lower the basement floor, after we finish the rest of the house. We already ran gas line, but there are still a few things to be done.

Mechanical room wall

Mechanical room wall

The boiler will be hung on the wall, and since the basement isn’t framed out that means it’s going on an outside wall. We don’t want to mount it directly on the brick because we want our house insulated and air sealed. That means we need to frame the outside wall where the boiler and panel will go. However, because we’re going to eventually lower the basement floor, we can’t just put a sill plate of the wall on the floor, we need to attach the studs to the brick wall. To ensure air and moisture management, we’ll use sill gasket behind the studs and fill the holes with caulk. The area between the studs we’ll fill with closed-cell spray foam.

Before any of that can happen, I need to prepare the wall. As is typical of our house, years ago someone saw a problem and went out about fixing it the wrong way. In this case, moisture problems with the brick foundation wall were not corrected by fixing gutters, redirecting storm water, or repointing the brick, they were “fixed” by slathering (parging) mortar or cement all over the brick wall on both sides in an effort to water seal it. This is generally a terrible idea because it traps water in the brick, rotting it from within. The ineffectiveness of this strategy is revealed by the coat of paint they put over the finished product which is now bubbled up and crumbling off.

So I’ve been removing the parging with my rotary hammer in chisel mode and a pry bar. It doesn’t need to be perfect, but the wall does need to be plumb. While the brick itself is pretty straight, the parging is thick enough in places to make for a wonky wall. Removing it is tricky because the parging doesn’t want to come off and it’s easy to damage the brick itself.

I also need to run electrical from the panel to the mechanical room. Chicago code requires EMT conduit, and in this case it’ll be ¾” because I need to run several circuits (lighting, hot water heater, boiler and pump, smoke detector, and eventually the air handler and HRV). I’m hoping to get both the wall prep and the electrical done by this Monday. With that out of the way we can get the hot water heater installed and focus on the remaining tasks for the boiler prep.

Choosing a Water Heater

For a while now I’ve been planning to get a Triangle Tube Smart Series indirect water heater. Indirect water heaters use the boiler to heat the water rather than have built-in heating elements. Lester, our radiant heating guy, agreed that it was a good design but cautioned that there can be issues with getting them approved by inspectors because they don’t have a double walled heat exchanger. I looked into the code and determined that we shouldn’t have an issue with that, but for a number of other reasons I wound up looking at other water heaters anyway.

The first is simplification. Our project is really complicated, with a set of interlocking pieces with dependencies and requirements across the gamut. Our existing water heater is in the way of our new boiler panel installation, so if we use an indirect water heater, we need to first move our existing water heater (disconnect everything, move it, and run water and gas plumbing to the new location along with exhaust flue to the chimney). Then we’d get the new boiler installed along with the indirect water heater, and re-plumb the water lines to the new location. We wouldn’t be able to remove the chimney until the new system was fully up and running. Conversely, if we just buy a standalone water heater, we can install it soup-to-nuts and be done with it. The boiler install loses any other dependencies, the chimney isn’t waiting on anything else, and we don’t have a single point of failure (the boiler) down the road.

There’s a few other factors to consider. For one thing, when the home is tightly insulated our heating load will be quite low. Having an indirect water heater actually means we’d need to buy a bigger boiler. The boilers modulate, meaning they can run at different levels depending on load (25%-100%), but if the boiler needs to be bigger just to run the water heater, that 25% is still a much bigger value. Our plumber, Mariusz, recommended the AO Smith Vertex 100, and it’s easy to see why. It’s 96% efficient, it’s reliable, we’ll never run out of hot water, and it’s direct vent, so it uses outside air for combustion, which is important when we’re doing so much air sealing.

I’ve already decided against tankless. They draw too much gas (up to 199,000 btu) and they don’t work well in the Midwest where our cold water can be 50° F or less. I’ve decided against tankless hybrids since they seem unreliable. I’ve ruled out most of the other condensing storage models because they either cost more, produce less, are less reliable or some combination thereof. There are cheaper models that direct vent but in addition to not having as much capacity (first hour delivery not tank size), they’re more than 40% less efficient, easily costing more over their lifetime.

Vertex 100

Vertex 100

In the end, I did a cost comparison. The Smart Indirect is the cheapest until you factor in the cost of a bigger boiler. A lower efficiency direct vent water heater is cheap until you factor in the operating cost. The Vertex 100 is expensive, but its high efficiency will pay for itself. I also looked at a more expensive direct vent heater that had a stainless steel tank so it would last longer, but the payback wasn’t there. I’ve reached out to Mariusz to get the ball rolling. In the mean time our whole-house water filter showed up and I need to frame out the mechanical room wall.

Heating Things Up

One of the major projects in our remodel is replacing the heating system, and I’ve been thinking more about it recently because our house is chilly. I sometimes feel like living in our old house is actually a trip back in time, where I need to wear a house robe and slippers over layers of clothes just to fend off the cold. Our efforts to weather seal are hindered by a complete absence of insulation in the walls or ceiling.

First floor demoed

Currently we have an inefficient old boiler with steam radiators. There are three radiators on each floor with pipes running through the basement and up through the first floor to reach the second, plus a brick chimney in the center of the house that both the boiler and the water heater share.

The challenge is that we’re remodeling in phases (first floor then second) but we have one heating system. We’re planning to replace it with a new high efficiency boiler (which will direct vent rather than need a chimney) and radiant floor heating, in our case a system of panels that install on top of the subfloor and have pex tubing run through them. In order to finish the first floor, we need to remove the chimney, pipes, and radiators from it. That means that the old heating system will no longer work but the new system would only be installed on the first floor, leaving us without heat on the second floor.

Quik Trak

Because of this I had originally been looking at a radiant heating system that installed under the floor, so we could heat the second floor from below before we remodeled it. There are a few problems with this approach: it’s not as efficient as the above subfloor system because it has to radiate through an extra inch of (non-conductive) wood, we’re planning to replace the plank subfloor with OSB and installing the pex tubing to it would prevent us from doing that, and finally the new system will be sized for the highly-insulated walls we’ll eventually have and most likely will not be powerful enough to heat the second floor until the insulation is installed.

So, how can we heat the second floor if we can’t use the radiators and don’t yet have radiant floors? One option is the forced air system we’re planning to install for air conditioning and ventilation. We could get a furnace rather than a simple air handler and install the ductwork sooner rather than later. Because the ducts will go through the attic and basement, they won’t require significant intrusion into the second floor, just a vertical trunk that would go through our bedroom. It would also give us a supplemental way to heat in the event we ever had a problem with the radiant system. However, we still have the problem that this system, even if we wanted to install it, would most likely be sized for the eventual high levels of insulation, not our current drafty state of affairs and might not be up to the task. It’s also a large up-front expense that we were planning to put off for some time.

That brings us to the other option: space heaters. I started looking at electric baseboard and oil-filled heaters. While not a very cost effective way to heat a home,  neither are our steam radiators. It’s entirely possible that running electric heaters would cost less than running the boiler, considering Chicago’s electric rate just dropped to 5.424¢/kilowatt hour and the fact we’re only heating one floor. Next, I briefly explored the option of an electric heat pump, which is much more efficient and can cool as well as heat, but it also costs ten times as much to buy and for a temporary solution it just doesn’t make sense.

In addition to the operating costs, if we got electric heaters we’d also need to run new wiring to power them, plus we would need at least three of them given they’re limited to 1,500 watts each. Once I started thinking about running three new circuits, it occurred to me that for about the same amount of effort I could run one gas line and put in a vent-free natural gas heater. A gas heater would deliver several times the heat of an electric baseboard and cost much less to operate. Best of all, while not as cheap as baseboards, they’re fairly inexpensive.

GWD308

As with everything, there is a trade off. Vent-free heaters cause increased moisture in the house and can adversely affect indoor air quality. Unfortunately, the direct vent alternatives that put out the same amount of heat cost several times as much and are less efficient. Despite the concerns, vent free is safe and with the house being as drafty as it is I’m not too concerned. They have built in oxygen depletion sensors and we have a carbon monoxide detector as well.

My plan is to get one, install it, and see if it keeps the house warm and if it’s cheaper to operate. If so, we can get rid of the boiler and radiators right away. If not, we can keep using the radiators for now and only switch to the heater for the second floor when we have to remove the chimney.