The short answer: the heater is only part of the price
A water heater quote combines the unit, the labor, the parts that connect it and any code upgrades. Two quotes that look far apart may include different scope. One may include a new relief valve, a discharge pipe and haul-away, while the other lists only the tank. We do not publish dollar figures here, because they change and depend on the house.
The way to compare is to ask each plumber for the same list of inclusions and read the lines side by side. The table below shows the items that most often differ.
Line items to compare between quotes
Ask for each of these in writing.
| Item | Why it matters | What to ask |
|---|---|---|
| Unit type and size | Gas, electric, heat pump and tankless differ widely | What model, what capacity, what warranty? |
| Venting | Gas units need a safe vent path | Is the existing vent reused or replaced? |
| Connectors and valves | Old valves and lines often fail on reconnection | Are new shutoff valves and connectors included? |
| Relief valve and discharge pipe | Safety parts that must be correct | Are they new, and where does the pipe end? |
| Permit | Some work needs one | Who files it, and is the fee included? |
| Haul-away | The old tank has to go somewhere | Is removal included? |
Comparing water heater quotes?
Call and ask for the scope in writing before you decide.
Fuel type and the house
Swapping like for like is the simplest path. Changing fuel types or moving the heater adds work, such as a new gas line, a new circuit or a new vent. Heat pump water heaters need room and airflow, and they drain condensate. Tankless units usually need larger fuel supplies, as explained in our guide on tankless installation.
A cramped closet, a cellar with low headroom or a heater far from the vent all add labor. A plumber who has seen the space can quote more precisely than one who has only heard a description over the phone.
Emergency versus planned timing
A failed tank on a holiday weekend is priced differently from a planned replacement, because after-hours staffing costs more. If the heater is old but still working, planning the swap lets you compare offers and choose a date. If it is leaking, call at once, and the dispatcher explains how timing applies to your call.
Our water heater replacement page describes the emergency route, and the water heater installation page describes the planned one.
Repair or replace: a rule of thumb
A small part on a sound tank is usually worth repairing. A leaking tank is not repairable. If the repair is a large share of a new unit's price, or the heater has failed repeatedly, replacement is the better value. The plumber reads the serial number to find the age and explains the reasoning.
The questions that expose a thin quote
A quote that fits on a single line is a warning sign. Ask whether the price includes a new expansion tank where the plumbing requires one, whether the old heater is hauled away and whether the discharge pipe from the relief valve is replaced. Ask what happens if the plumber finds a corroded valve or a bad vent connection once the old tank is out.
Ask who pulls the permit if one is needed, and whether that cost is in the number. Ask what warranty comes with the labor and with the unit, and what the warranty requires of you. A written scope that answers each question is a better guide to value than the bottom-line figure.
Be careful with allowances. A quote that says to be determined for venting or electrical work can balloon after the job starts. A fixed price that names the work is easier to hold the plumber to.
Why the same heater can cost more in one house than another
A heater in an open cellar with a floor drain is a short job. The same heater in a finished closet on the second floor takes longer, because the old tank has to come down the stairs and the drain pan has to connect to a safe outlet. Labor reflects access, not just size.
Distance to the vent, the condition of the shutoff valves and the type of pipe all feed into the time. Copper and PEX connect with different fittings, and old galvanized nipples may snap when disturbed. A plumber who looks at the space first can usually give a tighter number than one who guesses.
Keeping the running costs in mind
The price of the unit is only part of the cost of owning a heater. Fuel or electricity, maintenance and expected life matter too. A higher efficiency unit may cost more at first and less to run. A cheaper unit may need replacing sooner.
Ask the plumber for the running characteristics of each option and compare them with your fuel prices. We do not promise savings, but a fair comparison helps you choose.
Derry notes that touch the price
Derry's code enforcement office at 603-432-6148 can confirm whether a permit applies to a water heater change at your address. A permit adds a step but protects you at resale and with insurers.
Derry has 13,776 housing units according to the 2014 to 2018 American Community Survey as reported by NH ELMI, spanning old farmhouses to later construction. Older homes can bring surprises such as corroded shutoff valves or undersized supply lines, so ask the plumber to inspect them before quoting.
Sources: derrynh.gov code enforcement. NH Employment Security ELMI community profile for Derry.
Frequently asked questions
Check scope. Differences usually come from the unit, venting work, permits, valves and haul-away. Compare line by line.
It can. After-hours and holiday calls cost more to staff, and the dispatcher can explain how that applies to your call.
It depends on your electricity costs and space. The plumber can lay out the tradeoff for your house without promising savings.
Some plumbers install customer-supplied units, but warranty on labor may change. Ask before you buy.
It can for some work. Call code enforcement at 603-432-6148, and the plumber will tell you if one is needed.
A clear price before work starts
Call for water heater replacement or installation in Derry.