3/15/2012 9:55:00 PM High water pressure can get you in hot water
RANDY WEST Courier Columnist email@example.com
Our home and hot water tank are 10 years old. This week the recirculating hot water pump died. The plumber who replaced the pump recommended that we think about replacing the hot water tank now before it dies on a Sunday morning. Also, the expansion tank was full of water (he said it should not have water in it) and he removed it and capped the connection. He left the expansion tank with me.
The tank is a Rheem 50 gallon, model number 41V50.
Should we replace it now while we can shop and compare, or wait for a Sunday morning?
A: In my inspection reports, I give the average life for water heaters (and furnaces, roofing, etc.). I give water heaters 15 to 20 years. This is because I see 15- to 20-year-old water heaters all the time. Electric water heaters seem to last a little longer.
That is not to say some units can't fail early. I sometimes see brand-new water heaters in 10-year-old homes. I assume some of these may have been replaced because the owners wanted a larger water heater. My wife drains a 40-gallon gas water heater with every shower. But I'm sure some were installed because the original water heater failed.
The model number you gave me is for a gas water heater. Rheem is a good brand. Here is what I look for: excessive rust in the burn chamber and/or on the supply lines over the water heater, and of course water stains on the unit or floor indicating a leak.
Other indications of problems are hard to detect in a home inspection. Is the water much hotter or colder on occasion? Some variance is normal on gas units; you may be catching it at the very hottest (burner just turned off) or least hot (burner just turned on). But if the water is much hotter or cooler on occasion, the gas control can be faltering. These are so expensive now, it's better to just replace an older water heater (a new water heater will come with a new gas control).
I am kind of surprised your hwc (hot water circulator) pump went out. I don't give a life expectancy for these in my report; I only give life expectancies for high-dollar items. But I have seen many of these last 20-plus years. I have also seen them go out when they are in garages and the water or power has been turned off, allowing them to freeze - or if they are operated with no water (from the water supply being turned off or the shutoff valve near the hwc pump being closed).
Expansion tanks usually have a longer life cycle than yours, too. I'm surprised the plumber removed and capped the expansion tank. This is not a major safety concern, but the expansion tank does have a useful function.
Both these components failing can suggest a problem with the water heater itself, e.g., a faulty gas control (water too hot), or that your water pressure is too high. Having the thermostat on maximum could also affect the durability of an hwc pump and/or expansion tank, although the tank should be on the cold water line. (There are tanks made for installation on the hot water, but I've only seen these a couple times in single family homes).
So, if there are no leaks, no excessive rust visible, and no "mood swings" in the hot water temperature, I would not recommend replacing a 10-year-old water heater. You should have five years left and could have more. Disclaimer: I did not visually inspect your home and water heater. The plumber may have seen other indications of failure that I am not aware of. I don't know the location of your water heater. If your water heater is in the laundry room, with no catch pan (typical in our area), and you just installed $50,000 of solid mahogany wood flooring, you should consider replacing the water heater (and installing a catch pan).
I hope this helps you. I may use this question and answer in a future column. (I don't put your full name or address in the column.)
Jim replied: The expansion tank is on the cold side (just checked). The plumber said it was doing no good to keep it on full of water. He removed it and capped it because he didn't have one with him and, since we discussed that we might replace the hot water tank, he said he would put a new expansion tank on as part of the replacement of the heater. My wife wants extremely hot water. So the thermostat control is usually set just below "HOT"! Also, our water pressure was very high. The plumber (from an established company here in Prescott) checked the pressure and it was over 100 psi. He showed me when he attached the gauge and turned on the water. He installed a pressure regulator and set it at 65 psi.
The circulator pump was definitely bad, as indicated by water on the garage floor. Luckily, I must have caught it right after it happened, because it had just started to form a puddle on the concrete by the water heater. And now that you mention it, we have had work done over the years and I know the plumbers didn't always unplug the circulator pump when they turned off the water.
As for the hot water tank, we don't get major water temperature swings. Just the usual that you described due to the gas cycling on and off. No leaks and no rust. Just set very high.
Perhaps I will just have a new expansion tank installed. Thanks again.-Jim
Randy West owns Professional Building Consultants in Prescott. He is state-certified and has performed more than 6,000 home inspections in the Prescott area. West serves on the Home Inspector Rules and Standards Committee for the Arizona Board of Technical Registration. Contact him at firstname.lastname@example.org.